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Marine Drugs
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Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology
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Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology

A special issue of Marine Drugs (ISSN 1660-3397).

Deadline for manuscript submissions: closed (30 June 2019) | Viewed by 108048

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editor

Dr. Antonio Trincone

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Guest Editor
Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Comprensorio Olivetti, Edificio 70, Via Campi Flegrei 34, I-80078 Pozzuoli, Napoli, Italy
Interests: biocatalysis; marine enzymes; marine glycosidases; marine biotechnology; oligosaccharides
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The interdisciplinary study of the complexity of marine habitats has increased knowledge of marine forms of life. Marine-originating biocatalysts are attractive to biocatalysis practitioners for novel biochemical and stereochemical features. An in-depth knowledge of the precise biological functions of genes, proteins and enzymes within the marine ecosystem is still considered one of the least developed fields of research; even though in recent years marine habitat has been recognized as an untapped source of novel enzymes and metabolites. Expanding the range of enzymes from marine organisms is one of the key points in future marine biotechnology roadmaps. In particular, the importance of marine biocatalysts is recognized when addressing the exploration of chemical and biological diversity for novel materials and products, and for biomass production and processing, both used in foresight analyses for future research in this field. Convincing examples, such as the specific diversity of molecular assets of biocatalysis using marine enzymes with respect to terrestrial counterparts, are increasingly reported in the literature regarding all marine sources (not only microorganisms and fungi, plants and animals, but also extremophiles and symbiotic microorganisms). Indeed the plasticity of biological adaptations of marine organisms to the wide range of environmental events in specific environments (temperature, salinity, tides, pressure, radiation, light, etc.) provides an enormous reservoir of interesting subjects for basic and applicative studies.

Processes using marine enzymes and marine biomasses are central in different biotechnological fields of applications: (i) in a biorefinery value-chain with marine enzymes for biochemical processes; (ii) in food industries for enzymatic procedures in seafood processing; (iii) in fields of fine chemicals—in pharmaceutical, cosmetics, agriculture and environmental sectors—enzymatic treatments are a tool to improve efficiency and selectivity for extraction/manipulation of structurally complex marine molecules to gain access to bioactive compounds and to provide complex core blocks for hemisynthesis; (iv) the field of marine biomarkers and applications in pollution monitoring (biosensor) and bioremediation could also be of high significance for the appreciation of marine sources for enzymes.

Preeminent conclusions by many scientists in the field of marine biotechnology emphasize that due to marine biological diversity and the specificity of biological metabolisms, the study of marine biocatalysts on a global scale is just starting and possesses huge potential for development and applications with industrial benefits.

In this Special Issue, along with contributions regarding the potential of marine enzymes as useful tools in biocatalysis, results of enzymatic bioprospecting in gross marine environments will also be acknowledged. In addition, studies about structural characterizations, biological functions and aspects related to the complexity of marine enzyme-based bioprocesses will be hosted.

Dr. Antonio Trincone
Guest Editor

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Marine Drugs is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

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11 pages, 5912 KiB  
Article
Biochemical Characterization and Elucidation of Action Pattern of a Novel Polysaccharide Lyase 6 Family Alginate Lyase from Marine Bacterium Flammeovirga sp. NJ-04
by Qian Li, Fu Hu, Benwei Zhu, Yun Sun and Zhong Yao
Mar. Drugs 2019, 17(6), 323; https://doi.org/10.3390/md17060323 - 31 May 2019
Cited by 20 | Viewed by 3255
Abstract
Alginate lyases have been widely used to prepare alginate oligosaccharides in food, agricultural, and medical industries. Therefore, discovering and characterizing novel alginate lyases with excellent properties has drawn increasing attention. Herein, a novel alginate lyase FsAlyPL6 of Polysaccharide Lyase (PL) 6 family is [...] Read more.
Alginate lyases have been widely used to prepare alginate oligosaccharides in food, agricultural, and medical industries. Therefore, discovering and characterizing novel alginate lyases with excellent properties has drawn increasing attention. Herein, a novel alginate lyase FsAlyPL6 of Polysaccharide Lyase (PL) 6 family is identified and biochemically characterized from Flammeovirga sp. NJ-04. It shows highest activity at 45 °C and could retain 50% of activity after being incubated at 45 °C for 1 h. The Thin-Layer Chromatography (TLC) and Electrospray Ionization Mass Spectrometry (ESI-MS) analysis indicates that FsAlyPL6 endolytically degrades alginate polysaccharide into oligosaccharides ranging from monosaccharides to pentasaccharides. In addition, the action pattern of the enzyme is also elucidated and the result suggests that FsAlyPL6 could recognize tetrasaccharide as the minimal substrate and cleave the glycosidic bonds between the subsites of −1 and +3. The research provides extended insights into the substrate recognition and degradation pattern of PL6 alginate lyases, which may further expand the application of alginate lyases. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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14 pages, 2051 KiB  
Article
Characterization of an Alkaline Alginate Lyase with pH-Stable and Thermo-Tolerance Property
by Yanan Wang, Xuehong Chen, Xiaolin Bi, Yining Ren, Qi Han, Yu Zhou, Yantao Han, Ruyong Yao and Shangyong Li
Mar. Drugs 2019, 17(5), 308; https://doi.org/10.3390/md17050308 - 24 May 2019
Cited by 44 | Viewed by 4054
Abstract
Alginate oligosaccharides (AOS) show versatile bioactivities. Although various alginate lyases have been characterized, enzymes with special characteristics are still rare. In this study, a polysaccharide lyase family 7 (PL7) alginate lyase-encoding gene, aly08, was cloned from the marine bacterium Vibrio sp. SY01 [...] Read more.
Alginate oligosaccharides (AOS) show versatile bioactivities. Although various alginate lyases have been characterized, enzymes with special characteristics are still rare. In this study, a polysaccharide lyase family 7 (PL7) alginate lyase-encoding gene, aly08, was cloned from the marine bacterium Vibrio sp. SY01 and expressed in Escherichia coli. The purified alginate lyase Aly08, with a molecular weight of 35 kDa, showed a specific activity of 841 U/mg at its optimal pH (pH 8.35) and temperature (45 °C). Aly08 showed good pH-stability, as it remained more than 80% of its initial activity in a wide pH range (4.0–10.0). Aly08 was also a thermo-tolerant enzyme that recovered 70.8% of its initial activity following heat shock treatment for 5 min. This study also demonstrated that Aly08 is a polyG-preferred enzyme. Furthermore, Aly08 degraded alginates into disaccharides and trisaccharides in an endo-manner. Its thermo-tolerance and pH-stable properties make Aly08 a good candidate for further applications. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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14 pages, 2826 KiB  
Article
Activity Improvement and Vital Amino Acid Identification on the Marine-Derived Quorum Quenching Enzyme MomL by Protein Engineering
by Jiayi Wang, Jing Lin, Yunhui Zhang, Jingjing Zhang, Tao Feng, Hui Li, Xianghong Wang, Qingyang Sun, Xiaohua Zhang and Yan Wang
Mar. Drugs 2019, 17(5), 300; https://doi.org/10.3390/md17050300 - 21 May 2019
Cited by 15 | Viewed by 4142
Abstract
MomL is a marine-derived quorum-quenching (QQ) lactonase which can degrade various N-acyl homoserine lactones (AHLs). Intentional modification of MomL may lead to a highly efficient QQ enzyme with broad application potential. In this study, we used a rapid and efficient method combining [...] Read more.
MomL is a marine-derived quorum-quenching (QQ) lactonase which can degrade various N-acyl homoserine lactones (AHLs). Intentional modification of MomL may lead to a highly efficient QQ enzyme with broad application potential. In this study, we used a rapid and efficient method combining error-prone polymerase chain reaction (epPCR), high-throughput screening and site-directed mutagenesis to identify highly active MomL mutants. In this way, we obtained two candidate mutants, MomLI144V and MomLV149A. These two mutants exhibited enhanced activities and blocked the production of pathogenic factors of Pectobacterium carotovorum subsp. carotovorum (Pcc). Besides, seven amino acids which are vital for MomL enzyme activity were identified. Substitutions of these amino acids (E238G/K205E/L254R) in MomL led to almost complete loss of its QQ activity. We then tested the effect of MomL and its mutants on Pcc-infected Chinese cabbage. The results indicated that MomL and its mutants (MomLL254R, MomLI144V, MomLV149A) significantly decreased the pathogenicity of Pcc. This study provides an efficient method for QQ enzyme modification and gives us new clues for further investigation on the catalytic mechanism of QQ lactonase. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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20 pages, 1218 KiB  
Article
Microbial Population Changes in Decaying Ascophyllum nodosum Result in Macroalgal-Polysaccharide-Degrading Bacteria with Potential Applicability in Enzyme-Assisted Extraction Technologies
by Maureen W. Ihua, Freddy Guihéneuf, Halimah Mohammed, Lekha M. Margassery, Stephen A. Jackson, Dagmar B. Stengel, David J. Clarke and Alan D. W. Dobson
Mar. Drugs 2019, 17(4), 200; https://doi.org/10.3390/md17040200 - 29 Mar 2019
Cited by 18 | Viewed by 4788
Abstract
Seaweeds are of significant interest in the food, pharmaceutical, and agricultural industries as they contain several commercially relevant bioactive compounds. Current extraction methods for macroalgal-derived metabolites are, however, problematic due to the complexity of the algal cell wall which hinders extraction efficiencies. The [...] Read more.
Seaweeds are of significant interest in the food, pharmaceutical, and agricultural industries as they contain several commercially relevant bioactive compounds. Current extraction methods for macroalgal-derived metabolites are, however, problematic due to the complexity of the algal cell wall which hinders extraction efficiencies. The use of advanced extraction methods, such as enzyme-assisted extraction (EAE), which involve the application of commercial algal cell wall degrading enzymes to hydrolyze the cell wall carbohydrate network, are becoming more popular. Ascophyllum nodosum samples were collected from the Irish coast and incubated in artificial seawater for six weeks at three different temperatures (18 °C, 25 °C, and 30 °C) to induce decay. Microbial communities associated with the intact and decaying macroalga were examined using Illumina sequencing and culture-dependent approaches, including the novel ichip device. The bacterial populations associated with the seaweed were observed to change markedly upon decay. Over 800 bacterial isolates cultured from the macroalga were screened for the production of algal cell wall polysaccharidases and a range of species which displayed multiple hydrolytic enzyme activities were identified. Extracts from these enzyme-active bacterial isolates were then used in EAE of phenolics from Fucus vesiculosus and were shown to be more efficient than commercial enzyme preparations in their extraction efficiencies. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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12 pages, 3068 KiB  
Article
Characteristics of a Novel Manganese Superoxide Dismutase of a Hadal Sea Cucumber (Paelopatides sp.) from the Mariana Trench
by Yanan Li, Xue Kong and Haibin Zhang
Mar. Drugs 2019, 17(2), 84; https://doi.org/10.3390/md17020084 - 01 Feb 2019
Cited by 16 | Viewed by 3251
Abstract
A novel, cold-adapted, and acid-base stable manganese superoxide dismutase (Ps-Mn-SOD) was cloned from hadal sea cucumber Paelopatides sp. The dimeric recombinant enzyme exhibited approximately 60 kDa in molecular weight, expressed activity from 0 °C to 70 °C with an optimal temperature of 0 [...] Read more.
A novel, cold-adapted, and acid-base stable manganese superoxide dismutase (Ps-Mn-SOD) was cloned from hadal sea cucumber Paelopatides sp. The dimeric recombinant enzyme exhibited approximately 60 kDa in molecular weight, expressed activity from 0 °C to 70 °C with an optimal temperature of 0 °C, and resisted wide pH values from 2.2–13.0 with optimal activity (> 70%) at pH 5.0–12.0. The Km and Vmax of Ps-Mn-SOD were 0.0329 ± 0.0040 mM and 9112 ± 248 U/mg, respectively. At tested conditions, Ps-Mn-SOD was relatively stable in divalent metal ion and other chemicals, such as β-mercaptoethanol, dithiothreitol, Tween 20, Triton X-100, and Chaps. Furthermore, the enzyme showed striking stability in 5 M urea or 4 M guanidine hydrochloride, resisted digestion by proteases, and tolerated a high hydrostatic pressure of 100 MPa. The resistance of Ps-Mn-SOD against low temperature, extreme acidity and alkalinity, chemicals, proteases, and high pressure make it a potential candidate in biopharmaceutical and nutraceutical fields. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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15 pages, 3215 KiB  
Article
Characterization of the Specific Mode of Action of a Chitin Deacetylase and Separation of the Partially Acetylated Chitosan Oligosaccharides
by Xian-Yu Zhu, Yong Zhao, Huai-Dong Zhang, Wen-Xia Wang, Hai-Hua Cong and Heng Yin
Mar. Drugs 2019, 17(2), 74; https://doi.org/10.3390/md17020074 - 22 Jan 2019
Cited by 20 | Viewed by 3846
Abstract
Partially acetylated chitosan oligosaccharides (COS), which consists of N-acetylglucosamine (GlcNAc) and glucosamine (GlcN) residues, is a structurally complex biopolymer with a variety of biological activities. Therefore, it is challenging to elucidate acetylation patterns and the molecular structure-function relationship of COS. Herein, the detailed [...] Read more.
Partially acetylated chitosan oligosaccharides (COS), which consists of N-acetylglucosamine (GlcNAc) and glucosamine (GlcN) residues, is a structurally complex biopolymer with a variety of biological activities. Therefore, it is challenging to elucidate acetylation patterns and the molecular structure-function relationship of COS. Herein, the detailed deacetylation pattern of chitin deacetylase from Saccharomyces cerevisiae, ScCDA2, was studied. Which solves the randomization of acetylation patterns during COS produced by chemical. ScCDA2 also exhibits about 8% and 20% deacetylation activity on crystalline chitin and colloid chitin, respectively. Besides, a method for separating and detecting partially acetylated chitosan oligosaccharides by high performance liquid chromatography and electrospray ionization mass spectrometry (HPLC-ESI-MS) system has been developed, which is fast and convenient, and can be monitored online. Mass spectrometry sequencing revealed that ScCDA2 produced COS with specific acetylation patterns of DAAA, ADAA, AADA, DDAA, DADA, ADDA and DDDA, respectively. ScCDA2 does not deacetylate the GlcNAc unit that is closest to the reducing end of the oligomer furthermore ScCDA2 has a multiple-attack deacetylation mechanism on chitin oligosaccharides. This specific mode of action significantly enriches the existing limited library of chitin deacetylase deacetylation patterns. This fully defined COS may be used in the study of COS structure and function. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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13 pages, 2923 KiB  
Article
Design and Synthesis of a Chitodisaccharide-Based Affinity Resin for Chitosanases Purification
by Shangyong Li, Linna Wang, Xuehong Chen, Mi Sun and Yantao Han
Mar. Drugs 2019, 17(1), 68; https://doi.org/10.3390/md17010068 - 21 Jan 2019
Cited by 5 | Viewed by 3234
Abstract
Chitooligosaccharides (CHOS) have gained increasing attention because of their important biological activities. Enhancing the efficiency of CHOS production essentially requires screening of novel chitosanase with unique characteristics. Therefore, a rapid and efficient one-step affinity purification procedure plays important roles in screening native chitosanases. [...] Read more.
Chitooligosaccharides (CHOS) have gained increasing attention because of their important biological activities. Enhancing the efficiency of CHOS production essentially requires screening of novel chitosanase with unique characteristics. Therefore, a rapid and efficient one-step affinity purification procedure plays important roles in screening native chitosanases. In this study, we report the design and synthesis of affinity resin for efficient purification of native chitosanases without any tags, using chitodisaccharides (CHDS) as an affinity ligand, to couple with Sepharose 6B via a spacer, cyanuric chloride. Based on the CHDS-modified affinity resin, a one-step affinity purification method was developed and optimized, and then applied to purify three typical glycoside hydrolase (GH) families: 46, 75, and 80 chitosanase. The three purified chitosanases were homogeneous with purities of greater than 95% and bioactivity recovery of more than 40%. Moreover, we also developed a rapid and efficient affinity purification procedure, in which tag-free chitosanase could be directly purified from supernatant of bacterial culture. The purified chitosanases samples using such a procedure had apparent homogeneity, with more than 90% purity and 10–50% yield. The novel purification methods established in this work can be applied to purify native chitosanases in various scales, such as laboratory and industrial scales. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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13 pages, 3092 KiB  
Article
Cloning, Expression and Characterization of a Novel Cold-adapted β-galactosidase from the Deep-sea Bacterium Alteromonas sp. ML52
by Jingjing Sun, Congyu Yao, Wei Wang, Zhiwei Zhuang, Junzhong Liu, Fangqun Dai and Jianhua Hao
Mar. Drugs 2018, 16(12), 469; https://doi.org/10.3390/md16120469 - 27 Nov 2018
Cited by 30 | Viewed by 4191
Abstract
The bacterium Alteromonas sp. ML52, isolated from deep-sea water, was found to synthesize an intracellular cold-adapted β-galactosidase. A novel β-galactosidase gene from strain ML52, encoding 1058 amino acids residues, was cloned and expressed in Escherichia coli. The enzyme belongs to glycoside hydrolase [...] Read more.
The bacterium Alteromonas sp. ML52, isolated from deep-sea water, was found to synthesize an intracellular cold-adapted β-galactosidase. A novel β-galactosidase gene from strain ML52, encoding 1058 amino acids residues, was cloned and expressed in Escherichia coli. The enzyme belongs to glycoside hydrolase family 2 and is active as a homotetrameric protein. The recombinant enzyme had maximum activity at 35 °C and pH 8 with a low thermal stability over 30 °C. The enzyme also exhibited a Km of 0.14 mM, a Vmax of 464.7 U/mg and a kcat of 3688.1 S−1 at 35 °C with 2-nitrophenyl-β-d-galactopyranoside as a substrate. Hydrolysis of lactose assay, performed using milk, indicated that over 90% lactose in milk was hydrolyzed after incubation for 5 h at 25 °C or 24 h at 4 °C and 10 °C, respectively. These properties suggest that recombinant Alteromonas sp. ML52 β-galactosidase is a potential biocatalyst for the lactose-reduced dairy industry. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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18 pages, 4325 KiB  
Article
Novel Enzyme Actions for Sulphated Galactofucan Depolymerisation and a New Engineering Strategy for Molecular Stabilisation of Fucoidan Degrading Enzymes
by Hang T. T. Cao, Maria D. Mikkelsen, Mateusz J. Lezyk, Ly M. Bui, Van T. T. Tran, Artem S. Silchenko, Mikhail I. Kusaykin, Thinh D. Pham, Bang H. Truong, Jesper Holck and Anne S. Meyer
Mar. Drugs 2018, 16(11), 422; https://doi.org/10.3390/md16110422 - 01 Nov 2018
Cited by 28 | Viewed by 4732
Abstract
Fucoidans from brown macroalgae have beneficial biomedical properties but their use as pharma products requires homogenous oligomeric products. In this study, the action of five recombinant microbial fucoidan degrading enzymes were evaluated on fucoidans from brown macroalgae: Sargassum mcclurei, Fucus evanescens, [...] Read more.
Fucoidans from brown macroalgae have beneficial biomedical properties but their use as pharma products requires homogenous oligomeric products. In this study, the action of five recombinant microbial fucoidan degrading enzymes were evaluated on fucoidans from brown macroalgae: Sargassum mcclurei, Fucus evanescens, Fucus vesiculosus, Turbinaria ornata, Saccharina cichorioides, and Undaria pinnatifida. The enzymes included three endo-fucoidanases (EC 3.2.1.-GH 107), FcnA2, Fda1, and Fda2, and two unclassified endo-fucoglucuronomannan lyases, FdlA and FdlB. The oligosaccharide product profiles were assessed by carbohydrate-polyacrylamide gel electrophoresis and size exclusion chromatography. The recombinant enzymes FcnA2, Fda1, and Fda2 were unstable but were stabilised by truncation of the C-terminal end (removing up to 40% of the enzyme sequence). All five enzymes catalysed degradation of fucoidans containing α(1→4)-linked l-fucosyls. Fda2 also degraded S. cichorioides and U. pinnatifida fucoidans that have α(1→3)-linked l-fucosyls in their backbone. In the stabilised form, Fda1 also cleaved α(1→3) bonds. For the first time, we also show that several enzymes catalyse degradation of S. mcclurei galactofucan-fucoidan, known to contain α(1→4) and α(1→3) linked l-fucosyls and galactosyl-β(1→3) bonds in the backbone. These data enhance our understanding of fucoidan degrading enzymes and their substrate preferences and may assist development of enzyme-assisted production of defined fuco-oligosaccharides from fucoidan substrates. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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11 pages, 4499 KiB  
Article
A Novel Cold-Adapted Leucine Dehydrogenase from Antarctic Sea-Ice Bacterium Pseudoalteromonas sp. ANT178
by Yatong Wang, Yanhua Hou, Yifan Wang, Lu Zheng, Xianlei Xu, Kang Pan, Rongqi Li and Quanfu Wang
Mar. Drugs 2018, 16(10), 359; https://doi.org/10.3390/md16100359 - 01 Oct 2018
Cited by 10 | Viewed by 3766
Abstract
l-tert-leucine and its derivatives are useful as pharmaceutical active ingredients, in which leucine dehydrogenase (LeuDH) is the key enzyme in their enzymatic conversions. In the present study, a novel cold-adapted LeuDH, psleudh, was cloned from psychrotrophic bacteria Pseudoalteromonas sp. [...] Read more.
l-tert-leucine and its derivatives are useful as pharmaceutical active ingredients, in which leucine dehydrogenase (LeuDH) is the key enzyme in their enzymatic conversions. In the present study, a novel cold-adapted LeuDH, psleudh, was cloned from psychrotrophic bacteria Pseudoalteromonas sp. ANT178, which was isolated from Antarctic sea-ice. Bioinformatics analysis of the gene psleudh showed that the gene was 1209 bp in length and coded for a 42.6 kDa protein containing 402 amino acids. PsLeuDH had conserved Phe binding site and NAD+ binding site, and belonged to a member of the Glu/Leu/Phe/Val dehydrogenase family. Homology modeling analysis results suggested that PsLeuDH exhibited more glycine residues, reduced proline residues, and arginine residues, which might be responsible for its catalytic efficiency at low temperature. The recombinant PsLeuDH (rPsLeuDH) was purified a major band with the high specific activity of 275.13 U/mg using a Ni-NTA affinity chromatography. The optimum temperature and pH for rPsLeuDH activity were 30 °C and pH 9.0, respectively. Importantly, rPsLeuDH retained at least 40% of its maximum activity even at 0 °C. Moreover, the activity of rPsLeuDH was the highest in the presence of 2.0 M NaCl. Substrate specificity and kinetic studies of rPsLeuDH demonstrated that l-leucine was the most suitable substrate, and the catalytic activity at low temperatures was ensured by maintaining a high kcat value. The results of the current study would provide insight into Antarctic sea-ice bacterium LeuDH, and the unique properties of rPsLeuDH make it a promising candidate as a biocatalyst in medical and pharmaceutical industries. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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22 pages, 2797 KiB  
Article
Characterization of Properties and Transglycosylation Abilities of Recombinant α-Galactosidase from Cold-Adapted Marine Bacterium Pseudoalteromonas KMM 701 and Its C494N and D451A Mutants
by Irina Bakunina, Lubov Slepchenko, Stanislav Anastyuk, Vladimir Isakov, Galina Likhatskaya, Natalya Kim, Liudmila Tekutyeva, Oksana Son and Larissa Balabanova
Mar. Drugs 2018, 16(10), 349; https://doi.org/10.3390/md16100349 - 24 Sep 2018
Cited by 13 | Viewed by 3578
Abstract
A novel wild-type recombinant cold-active α-d-galactosidase (α-PsGal) from the cold-adapted marine bacterium Pseudoalteromonas sp. KMM 701, and its mutants D451A and C494N, were studied in terms of their structural, physicochemical, and catalytic properties. Homology models of the three-dimensional α-PsGal structure, its [...] Read more.
A novel wild-type recombinant cold-active α-d-galactosidase (α-PsGal) from the cold-adapted marine bacterium Pseudoalteromonas sp. KMM 701, and its mutants D451A and C494N, were studied in terms of their structural, physicochemical, and catalytic properties. Homology models of the three-dimensional α-PsGal structure, its active center, and complexes with D-galactose were constructed for identification of functionally important amino acid residues in the active site of the enzyme, using the crystal structure of the α-galactosidase from Lactobacillus acidophilus as a template. The circular dichroism spectra of the wild α-PsGal and mutant C494N were approximately identical. The C494N mutation decreased the efficiency of retaining the affinity of the enzyme to standard p-nitrophenyl-α-galactopiranoside (pNP-α-Gal). Thin-layer chromatography, matrix-assisted laser desorption/ionization mass spectrometry, and nuclear magnetic resonance spectroscopy methods were used to identify transglycosylation products in reaction mixtures. α-PsGal possessed a narrow acceptor specificity. Fructose, xylose, fucose, and glucose were inactive as acceptors in the transglycosylation reaction. α-PsGal synthesized -α(1→6)- and -α(1→4)-linked galactobiosides from melibiose as well as -α(1→6)- and -α(1→3)-linked p-nitrophenyl-digalactosides (Gal2-pNP) from pNP-α-Gal. The D451A mutation in the active center completely inactivated the enzyme. However, the substitution of C494N discontinued the Gal-α(1→3)-Gal-pNP synthesis and increased the Gal-α(1→4)-Gal yield compared to Gal-α(1→6)-Gal-pNP. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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13 pages, 3918 KiB  
Article
Biochemical Characterization and Degradation Pattern of a Novel Endo-Type Bifunctional Alginate Lyase AlyA from Marine Bacterium Isoptericola halotolerans
by Benwei Zhu, Limin Ning, Yucui Jiang and Lin Ge
Mar. Drugs 2018, 16(8), 258; https://doi.org/10.3390/md16080258 - 31 Jul 2018
Cited by 18 | Viewed by 3836
Abstract
Alginate lyases are important tools to prepare oligosaccharides with various physiological activities by degrading alginate. Particularly, the bifunctional alginate lyase can efficiently hydrolyze the polysaccharide into oligosaccharides. Herein, we cloned and identified a novel bifunctional alginate lyase, AlyA, with a high activity and [...] Read more.
Alginate lyases are important tools to prepare oligosaccharides with various physiological activities by degrading alginate. Particularly, the bifunctional alginate lyase can efficiently hydrolyze the polysaccharide into oligosaccharides. Herein, we cloned and identified a novel bifunctional alginate lyase, AlyA, with a high activity and broad substrate specificity from bacterium Isoptericola halotolerans NJ-05 for oligosaccharides preparation. For further applications in industry, the enzyme has been characterized and its action mode has been also elucidated. It exhibited the highest activity (7984.82 U/mg) at pH 7.5 and 55 °C. Additionally, it possessed a broad substrate specificity, showing high activities towards not only polyM (polyβ-d-mannuronate) (7658.63 U/mg), but also polyG (poly α-l-guluronate) (8643.29 U/mg). Furthermore, the Km value of AlyA towards polyG (3.2 mM) was lower than that towards sodium alginate (5.6 mM) and polyM (6.7 mM). TLC (Thin Layer Chromatography) and ESI-MS (Electrospray Ionization Mass Spectrometry) were used to study the action mode of the enzyme, showing that it can hydrolyze the substrates in an endolytic manner to release a series of oligosaccharides such as disaccharide, trisaccharide, and tetrasaccharide. This study provided extended insights into the substrate recognition and degrading pattern of the alginate lyases, with a broad substrate specificity. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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12 pages, 18465 KiB  
Article
Biochemical Characterization and Degradation Pattern of a Unique pH-Stable PolyM-Specific Alginate Lyase from Newly Isolated Serratia marcescens NJ-07
by Benwei Zhu, Fu Hu, Heng Yuan, Yun Sun and Zhong Yao
Mar. Drugs 2018, 16(4), 129; https://doi.org/10.3390/md16040129 - 15 Apr 2018
Cited by 31 | Viewed by 4506
Abstract
Enzymatic preparation of alginate oligosaccharides with versatile bioactivities by alginate lyases has attracted increasing attention due to its featured characteristics, such as wild condition and specific products. In this study, AlgNJ-07, a novel polyM-specific alginate lyase with high specific activity and pH stability, [...] Read more.
Enzymatic preparation of alginate oligosaccharides with versatile bioactivities by alginate lyases has attracted increasing attention due to its featured characteristics, such as wild condition and specific products. In this study, AlgNJ-07, a novel polyM-specific alginate lyase with high specific activity and pH stability, has been purified from the newly isolated marine bacterium Serratia marcescens NJ-07. It has a molecular weight of approximately 25 kDa and exhibits the maximal activity of 2742.5 U/mg towards sodium alginate under 40 °C at pH 9.0. Additionally, AlgNJ-07 could retain more than 95% of its activity at pH range of 8.0–10.0, indicating it possesses excellent pH-stability. Moreover, it shows high activity and affinity towards polyM block and no activity to polyG block, which suggests that it is a strict polyM-specific alginate lyase. The degradation pattern of AlgNJ-07 has also been explored. The activity of AlgNJ-07 could be activated by NaCl with a low concentration (100–300 mM). It can be observed that AlgNJ-07 can recognize the trisaccharide as the minimal substrate and hydrolyze the trisaccharide into monosaccharide and disaccharide. The TLC and ESI-MS analysis indicate that it can hydrolyze substrates in a unique endolytic manner, producing not only oligosaccharides with Dp of 2–5 but also a large fraction of monosaccharide. Therefore, it may be a potent tool to produce alginate oligosaccharides with lower Dps (degree of polymerization). Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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13 pages, 4685 KiB  
Article
AlgM4: A New Salt-Activated Alginate Lyase of the PL7 Family with Endolytic Activity
by Guiyuan Huang, Qiaozhen Wang, Mingqian Lu, Chao Xu, Fei Li, Rongcan Zhang, Wei Liao and Shushi Huang
Mar. Drugs 2018, 16(4), 120; https://doi.org/10.3390/md16040120 - 06 Apr 2018
Cited by 39 | Viewed by 4479
Abstract
Alginate lyases are a group of enzymes that catalyze the depolymerization of alginates into oligosaccharides or monosaccharides. These enzymes have been widely used for a variety of purposes, such as producing bioactive oligosaccharides, controlling the rheological properties of polysaccharides, and performing structural analyses [...] Read more.
Alginate lyases are a group of enzymes that catalyze the depolymerization of alginates into oligosaccharides or monosaccharides. These enzymes have been widely used for a variety of purposes, such as producing bioactive oligosaccharides, controlling the rheological properties of polysaccharides, and performing structural analyses of polysaccharides. The algM4 gene of the marine bacterium Vibrio weizhoudaoensis M0101 encodes an alginate lyase that belongs to the polysaccharide lyase family 7 (PL7). In this study, the kinetic constants Vmax (maximum reaction rate) and Km (Michaelis constant) of AlgM4 activity were determined as 2.75 nmol/s and 2.72 mg/mL, respectively. The optimum temperature for AlgM4 activity was 30 °C, and at 70 °C, AlgM4 activity dropped to 11% of the maximum observed activity. The optimum pH for AlgM4 activity was 8.5, and AlgM4 was completely inactive at pH 11. The addition of 1 mol/L NaCl resulted in a more than sevenfold increase in the relative activity of AlgM4. The secondary structure of AlgM4 was altered in the presence of NaCl, which caused the α-helical content to decrease from 12.4 to 10.8% and the β-sheet content to decrease by 1.7%. In addition, NaCl enhanced the thermal stability of AlgM4 and increased the midpoint of thermal denaturation (Tm) by 4.9 °C. AlgM4 exhibited an ability to degrade sodium alginate, poly-mannuronic acid (polyM), and poly-guluronic acid (polyG), resulting in the production of oligosaccharides with a degree of polymerization (DP) of 2–9. AlgM4 possessed broader substrate, indicating that it is a bifunctional alginate lyase. Thus, AlgM4 is a novel salt-activated and bifunctional alginate lyase of the PL7 family with endolytic activity. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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13 pages, 1968 KiB  
Article
Purification and Characterization of a Novel Alginate Lyase from the Marine Bacterium Bacillus sp. Alg07
by Peng Chen, Yueming Zhu, Yan Men, Yan Zeng and Yuanxia Sun
Mar. Drugs 2018, 16(3), 86; https://doi.org/10.3390/md16030086 - 09 Mar 2018
Cited by 49 | Viewed by 7721
Abstract
Alginate oligosaccharides with different bioactivities can be prepared through the specific degradation of alginate by alginate lyases. Therefore, alginate lyases that can be used to degrade alginate under mild conditions have recently attracted public attention. Although various types of alginate lyases have been [...] Read more.
Alginate oligosaccharides with different bioactivities can be prepared through the specific degradation of alginate by alginate lyases. Therefore, alginate lyases that can be used to degrade alginate under mild conditions have recently attracted public attention. Although various types of alginate lyases have been discovered and characterized, few can be used in industrial production. In this study, AlgA, a novel alginate lyase with high specific activity, was purified from the marine bacterium Bacillus sp. Alg07. AlgA had a molecular weight of approximately 60 kDa, an optimal temperature of 40 °C, and an optimal pH of 7.5. The activity of AlgA was dependent on sodium chloride and could be considerably enhanced by Mg2+ or Ca2+. Under optimal conditions, the activity of AlgA reached up to 8306.7 U/mg, which is the highest activity recorded for alginate lyases. Moreover, the enzyme was stable over a broad pH range (5.0–10.0), and its activity negligibly changed after 24 h of incubation at 40 °C. AlgA exhibited high activity and affinity toward poly-β-d-mannuronate (polyM). These characteristics suggested that AlgA is an endolytic polyM-specific alginate lyase (EC 4.2.2.3). The products of alginate and polyM degradation by AlgA were purified and identified through fast protein liquid chromatography and electrospray ionization mass spectrometry, which revealed that AlgA mainly produced disaccharides, trisaccharides, and tetrasaccharide from alginate and disaccharides and trisaccharides from polyM. Therefore, the novel lysate AlgA has potential applications in the production of mannuronic oligosaccharides and poly-α-l-guluronate blocks from alginate. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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15 pages, 1084 KiB  
Article
A Comparative Study on Asymmetric Reduction of Ketones Using the Growing and Resting Cells of Marine-Derived Fungi
by Hui Liu, Bi-Shuang Chen, Fayene Zeferino Ribeiro De Souza and Lan Liu
Mar. Drugs 2018, 16(2), 62; https://doi.org/10.3390/md16020062 - 14 Feb 2018
Cited by 15 | Viewed by 4041
Abstract
Whole-cell biocatalysts offer a highly enantioselective, minimally polluting route to optically active alcohols. Currently, most of the whole-cell catalytic performance involves resting cells rather than growing cell biotransformation, which is one-step process that benefits from the simultaneous growth and biotransformation, eliminating the need [...] Read more.
Whole-cell biocatalysts offer a highly enantioselective, minimally polluting route to optically active alcohols. Currently, most of the whole-cell catalytic performance involves resting cells rather than growing cell biotransformation, which is one-step process that benefits from the simultaneous growth and biotransformation, eliminating the need for catalysts preparation. In this paper, asymmetric reduction of 14 aromatic ketones to the corresponding enantiomerically pure alcohols was successfully conducted using the growing and resting cells of marine-derived fungi under optimized conditions. Good yields and excellent enantioselectivities were achieved with both methods. Although substrate inhibition might be a limiting factor for growing cell biotransformation, the selected strain can still completely convert 10-mM substrates into the desired products. The resting cell biotransformation showed a capacity to be recycled nine times without a significant decrease in the activity. This is the first study to perform asymmetric reduction of ketones by one-step growing cell biotransformation. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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16 pages, 7623 KiB  
Article
Purification and Characterization of a Biofilm-Degradable Dextranase from a Marine Bacterium
by Wei Ren, Ruanhong Cai, Wanli Yan, Mingsheng Lyu, Yaowei Fang and Shujun Wang
Mar. Drugs 2018, 16(2), 51; https://doi.org/10.3390/md16020051 - 07 Feb 2018
Cited by 43 | Viewed by 4891
Abstract
This study evaluated the ability of a dextranase from a marine bacterium Catenovulum sp. (Cadex) to impede formation of Streptococcus mutans biofilms, a primary pathogen of dental caries, one of the most common human infectious diseases. Cadex was purified 29.6-fold and had a [...] Read more.
This study evaluated the ability of a dextranase from a marine bacterium Catenovulum sp. (Cadex) to impede formation of Streptococcus mutans biofilms, a primary pathogen of dental caries, one of the most common human infectious diseases. Cadex was purified 29.6-fold and had a specific activity of 2309 U/mg protein and molecular weight of 75 kDa. Cadex showed maximum activity at pH 8.0 and 40 °C and was stable at temperatures under 30 °C and at pH ranging from 5.0 to 11.0. A metal ion and chemical dependency study showed that Mn2+ and Sr2+ exerted positive effects on Cadex, whereas Cu2+, Fe3+, Zn2+, Cd2+, Ni2+, and Co2+ functioned as inhibitors. Several teeth rinsing product reagents, including carboxybenzene, ethanol, sodium fluoride, and xylitol were found to have no effects on Cadex activity. A substrate specificity study showed that Cadex specifically cleaved the α-1,6 glycosidic bond. Thin layer chromatogram and high-performance liquid chromatography indicated that the main hydrolysis products were isomaltoogligosaccharides. Crystal violet staining and scanning electron microscopy showed that Cadex impeded the formation of S. mutans biofilm to some extent. In conclusion, Cadex from a marine bacterium was shown to be an alkaline and cold-adapted endo-type dextranase suitable for development of a novel marine agent for the treatment of dental caries. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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11 pages, 2745 KiB  
Article
Microbial Degradation of Amino Acid-Containing Compounds Using the Microcystin-Degrading Bacterial Strain B-9
by Haiyan Jin, Yoshiko Hiraoka, Yurie Okuma, Elisabete Hiromi Hashimoto, Miki Kurita, Andrea Roxanne J. Anas, Hitoshi Uemura, Kiyomi Tsuji and Ken-Ichi Harada
Mar. Drugs 2018, 16(2), 50; https://doi.org/10.3390/md16020050 - 06 Feb 2018
Cited by 9 | Viewed by 4472
Abstract
Strain B-9, which has a 99% similarity to Sphingosinicella microcystinivorans strain Y2, is a Gram-negative bacterium with potential for use in the degradation of microcystin-related compounds and nodularin. We attempted to extend the application area of strain B-9 and applied it to mycotoxins [...] Read more.
Strain B-9, which has a 99% similarity to Sphingosinicella microcystinivorans strain Y2, is a Gram-negative bacterium with potential for use in the degradation of microcystin-related compounds and nodularin. We attempted to extend the application area of strain B-9 and applied it to mycotoxins produced by fungi. Among the tested mycotoxins, only ochratoxin A was completely hydrolyzed to provide the constituents ochratoxin α and l-phenylalanine, and levels of fumonisin B1 gradually decreased after 96 h. However, although drugs including antibiotics released into the aquatic environment were applied for microbial degradation using strain B-9, no degradation occurred. These results suggest that strain B-9 can only degrade amino acid-containing compounds. As expected, the tested compounds with amide and ester bonds, such as 3,4-dimethyl hippuric acid and 4-benzyl aspartate, were readily hydrolyzed by strain B-9, although the sulfonamides remained unchanged. The ester compounds were characteristically and rapidly hydrolyzed as soon as they came into contact with strain B-9. Furthermore, the degradation of amide and ester compounds with amino acids was not inhibited by the addition of ethylenediaminetetraacetic acid (EDTA), indicating that the responsible enzyme was not MlrC. These results suggest that strain B-9 possesses an additional hydrolytic enzyme that should be designated as MlrE, as well as an esterase. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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2049 KiB  
Article
Optimization of Collagenase Production by Pseudoalteromonas sp. SJN2 and Application of Collagenases in the Preparation of Antioxidative Hydrolysates
by Xinghao Yang, Xiao Xiao, Dan Liu, Ribang Wu, Cuiling Wu, Jiang Zhang, Jiafeng Huang, Binqiang Liao and Hailun He
Mar. Drugs 2017, 15(12), 377; https://doi.org/10.3390/md15120377 - 04 Dec 2017
Cited by 22 | Viewed by 5178
Abstract
Collagenases are the most important group of commercially-produced enzymes. However, even though biological resources are abundant in the sea, very few of these commercially popular enzymes are from marine sources, especially from marine bacteria. We optimized the production of marine collagenases by Pseudoalteromonas [...] Read more.
Collagenases are the most important group of commercially-produced enzymes. However, even though biological resources are abundant in the sea, very few of these commercially popular enzymes are from marine sources, especially from marine bacteria. We optimized the production of marine collagenases by Pseudoalteromonas sp. SJN2 and investigated the antioxidant activities of the hydrolysates. Media components and culture conditions associated with marine collagenase production by Pseudoalteromonas sp. SJN2 were optimized by statistical methods, namely Plackett–Burman design and response surface methodology (RSM). Furthermore, the marine collagenases produced by Pseudoalteromonas sp. SJN2 were seen to efficiently hydrolyze marine collagens extracted from fish by-products, and remarkable antioxidant capacities of the enzymatic hydrolysates were shown by DPPH radical scavenging and oxygen radical absorbance capacity (ORAC) tests. The final optimized fermentation conditions were as follows: soybean powder, 34.23 g·L−1; culture time, 3.72 d; and temperature, 17.32 °C. Under the optimal fermentation conditions, the experimental collagenase yield obtained was 322.58 ± 9.61 U·mL−1, which was in agreement with the predicted yield of 306.68 U·mL−1. Collagen from Spanish mackerel bone, seabream scale and octopus flesh also showed higher DPPH radical scavenging rates and ORAC values after hydrolysis by the collagenase. This study may have implications for the development and use of marine collagenases. Moreover, seafood waste containing beneficial collagen could be used to produce antioxidant peptides by proteolysis. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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6545 KiB  
Article
Identification of 2-keto-3-deoxy-d-Gluconate Kinase and 2-keto-3-deoxy-d-Phosphogluconate Aldolase in an Alginate-Assimilating Bacterium, Flavobacterium sp. Strain UMI-01
by Ryuji Nishiyama, Akira Inoue and Takao Ojima
Mar. Drugs 2017, 15(2), 37; https://doi.org/10.3390/md15020037 - 14 Feb 2017
Cited by 16 | Viewed by 5440
Abstract
Recently, we identified an alginate-assimilating gene cluster in the genome of Flavobacterium sp. strain UMI-01, a member of Bacteroidetes. Alginate lyase genes and a 4-deoxy-l-erythro-5-hexoseulose uronic acid (DEH) reductase gene in the cluster have already been characterized; however, 2-keto-3-deoxy-d [...] Read more.
Recently, we identified an alginate-assimilating gene cluster in the genome of Flavobacterium sp. strain UMI-01, a member of Bacteroidetes. Alginate lyase genes and a 4-deoxy-l-erythro-5-hexoseulose uronic acid (DEH) reductase gene in the cluster have already been characterized; however, 2-keto-3-deoxy-d-gluconate (KDG) kinase and 2-keto-3-deoxy-6-phosphogluconate (KDPG) aldolase genes, i.e., flkin and flald, still remained uncharacterized. The amino acid sequences deduced from flkin and flald showed low identities with those of corresponding enzymes of Saccharophagus degradans 2-40T, a member of Proteobacteria (Kim et al., Process Biochem., 2016). This led us to consider that the DEH-assimilating enzymes of Bacteroidetes species are somewhat deviated from those of Proteobacteria species. Thus, in the present study, we first assessed the characteristics in the primary structures of KDG kinase and KDG aldolase of the strain UMI-01, and then investigated the enzymatic properties of recombinant enzymes, recFlKin and recFlAld, expressed by an Escherichia coli expression system. Multiple-sequence alignment among KDG kinases and KDG aldolases from several Proteobacteria and Bacteroidetes species indicated that the strain UMI-01 enzymes showed considerably low sequence identities (15%–25%) with the Proteobacteria enzymes, while they showed relatively high identities (47%–68%) with the Bacteroidetes enzymes. Phylogenetic analyses for these enzymes indicated the distant relationship between the Proteobacteria enzymes and the Bacteroidetes enzymes, i.e., they formed distinct clusters in the phylogenetic tree. recFlKin and recFlAld produced with the genes flkin and flald, respectively, were confirmed to show KDG kinase and KDPG aldolase activities. Namely, recFlKin produced 1.7 mM KDPG in a reaction mixture containing 2.5 mM KDG and 2.5 mM ATP in a 90-min reaction, while recFlAld produced 1.2 mM pyruvate in the reaction mixture containing 5 mM KDPG at the equilibrium state. An in vitro alginate-metabolizing system constructed from recFlKin, recFlAld, and previously reported alginate lyases and DEH reductase of the strain UMI-01 could convert alginate to pyruvate and glyceraldehyde-3-phosphate with an efficiency of 38%. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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1877 KiB  
Article
Structure-Based Design and Synthesis of a New Phenylboronic-Modified Affinity Medium for Metalloprotease Purification
by Shangyong Li, Linna Wang, Ximing Xu, Shengxiang Lin, Yuejun Wang, Jianhua Hao and Mi Sun
Mar. Drugs 2017, 15(1), 5; https://doi.org/10.3390/md15010005 - 27 Dec 2016
Cited by 2 | Viewed by 5643
Abstract
Metalloproteases are emerging as useful agents in the treatment of many diseases including arthritis, cancer, cardiovascular diseases, and fibrosis. Studies that could shed light on the metalloprotease pharmaceutical applications require the pure enzyme. Here, we reported the structure-based design and synthesis of the [...] Read more.
Metalloproteases are emerging as useful agents in the treatment of many diseases including arthritis, cancer, cardiovascular diseases, and fibrosis. Studies that could shed light on the metalloprotease pharmaceutical applications require the pure enzyme. Here, we reported the structure-based design and synthesis of the affinity medium for the efficient purification of metalloprotease using the 4-aminophenylboronic acid (4-APBA) as affinity ligand, which was coupled with Sepharose 6B via cyanuric chloride as spacer. The molecular docking analysis showed that the boron atom was interacting with the hydroxyl group of Ser176 residue, whereas the hydroxyl group of the boronic moiety is oriented toward Leu175 and His177 residues. In addition to the covalent bond between the boron atom and hydroxyl group of Ser176, the spacer between boronic acid derivatives and medium beads contributes to the formation of an enzyme-medium complex. With this synthesized medium, we developed and optimized a one-step purification procedure and applied it for the affinity purification of metalloproteases from three commercial enzyme products. The native metalloproteases were purified to high homogeneity with more than 95% purity. The novel purification method developed in this work provides new opportunities for scientific, industrial and pharmaceutical projects. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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Review

Jump to: Research

20 pages, 1989 KiB  
Review
Microalgal Enzymes with Biotechnological Applications
by Giorgio Maria Vingiani, Pasquale De Luca, Adrianna Ianora, Alan D.W. Dobson and Chiara Lauritano
Mar. Drugs 2019, 17(8), 459; https://doi.org/10.3390/md17080459 - 05 Aug 2019
Cited by 45 | Viewed by 6448
Abstract
Enzymes are essential components of biological reactions and play important roles in the scaling and optimization of many industrial processes. Due to the growing commercial demand for new and more efficient enzymes to help further optimize these processes, many studies are now focusing [...] Read more.
Enzymes are essential components of biological reactions and play important roles in the scaling and optimization of many industrial processes. Due to the growing commercial demand for new and more efficient enzymes to help further optimize these processes, many studies are now focusing their attention on more renewable and environmentally sustainable sources for the production of these enzymes. Microalgae are very promising from this perspective since they can be cultivated in photobioreactors, allowing the production of high biomass levels in a cost-efficient manner. This is reflected in the increased number of publications in this area, especially in the use of microalgae as a source of novel enzymes. In particular, various microalgal enzymes with different industrial applications (e.g., lipids and biofuel production, healthcare, and bioremediation) have been studied to date, and the modification of enzymatic sequences involved in lipid and carotenoid production has resulted in promising results. However, the entire biosynthetic pathways/systems leading to synthesis of potentially important bioactive compounds have in many cases yet to be fully characterized (e.g., for the synthesis of polyketides). Nonetheless, with recent advances in microalgal genomics and transcriptomic approaches, it is becoming easier to identify sequences encoding targeted enzymes, increasing the likelihood of the identification, heterologous expression, and characterization of these enzymes of interest. This review provides an overview of the state of the art in marine and freshwater microalgal enzymes with potential biotechnological applications and provides future perspectives for this field. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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605 KiB  
Review
Enzymatic Processes in Marine Biotechnology
by Antonio Trincone
Mar. Drugs 2017, 15(4), 93; https://doi.org/10.3390/md15040093 - 25 Mar 2017
Cited by 30 | Viewed by 6757
Abstract
In previous review articles the attention of the biocatalytically oriented scientific community towards the marine environment as a source of biocatalysts focused on the habitat-related properties of marine enzymes. Updates have already appeared in the literature, including marine examples of oxidoreductases, hydrolases, transferases, [...] Read more.
In previous review articles the attention of the biocatalytically oriented scientific community towards the marine environment as a source of biocatalysts focused on the habitat-related properties of marine enzymes. Updates have already appeared in the literature, including marine examples of oxidoreductases, hydrolases, transferases, isomerases, ligases, and lyases ready for food and pharmaceutical applications. Here a new approach for searching the literature and presenting a more refined analysis is adopted with respect to previous surveys, centering the attention on the enzymatic process rather than on a single novel activity. Fields of applications are easily individuated: (i) the biorefinery value-chain, where the provision of biomass is one of the most important aspects, with aquaculture as the prominent sector; (ii) the food industry, where the interest in the marine domain is similarly developed to deal with the enzymatic procedures adopted in food manipulation; (iii) the selective and easy extraction/modification of structurally complex marine molecules, where enzymatic treatments are a recognized tool to improve efficiency and selectivity; and (iv) marine biomarkers and derived applications (bioremediation) in pollution monitoring are also included in that these studies could be of high significance for the appreciation of marine bioprocesses. Full article
(This article belongs to the Special Issue Marine Enzymes: Sources, Biochemistry and Bioprocesses for Marine Biotechnology)
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