Search Results (158)

Brevibacillus laterosporus strain B.O.D. is a well-established commercial probiotic and antimicrobial microorganism that finds use in human health and in agriculture as a biofertilizer. On the other hand, while B. laterosporus is a well-known entomopathogenic species, the possible insecticidal potential of strain B.O.D. remains unexplored. To address this knowledge gap, this study combined genome sequencing and comparative analysis with other B. laterospours strains and insect bioassays. The genome of B. laterosporus B.O.D. was found to harbor a wide range of genes related to entomopathogenicity encoding putative proteases, chitinases, collagenase-like proteases, mosquitocidal proteins, bacillolysin, and spore-surface proteins. Antimicrobial compounds such as gramicidin and surfactin were also found. Sequence alignment with other well-characterized B. laterosporus strains and analysis revealed significant differences, which support the corresponding differences in insecticidal activity observed when comparing strain B.O.D. with others against a variety of lepidopteran and dipteran pest species. This study reports for the first time the genome of strain B.O.D., providing a comparative analysis and highlighting its insecticidal properties, which appear more moderate compared to previously characterized entomopathogenic strains of the same species. Everything considered, B. laterosporus strain B.O.D. appears to be remarkably versatile, underscoring wide biotechnological potential. Full article

The fruiting bodies of shiitake mushrooms (Lentinula edodes) are highly susceptible to postharvest quality deterioration due to their loose tissue, high moisture, and active metabolism. Low-dose ultraviolet-C (UV-C) irradiation, a green, safe, low-cost, and efficient physical treatment especially suitable for high-moisture and metabolically active produce, offers a promising solution to this problem for the postharvest preservation of shiitake mushrooms. In this study, the effects of different doses of UV-C irradiation (2.5, 5.0, and 7.5 kJ·m⁻²) on the postharvest quality of shiitake mushrooms were systematically compared by measuring weight loss, respiration intensity, cap opening percentage, firmness, color (L*, a*, b*), electrolyte leakage, MDA content, antioxidant enzyme activities (SOD, CAT, POD, PAL), chitin content, chitinase activity, and the expression of LeCHI and LeCDA genes. The results showed that UV-C irradiation at 5 kJ m⁻² significantly delayed the increase in weight loss (by approximately 32% at day 15 compared to control) and reduced respiration rate (by 25–35% during days 3–9) and cap opening rate (27.3% vs. 48.0% in control at day 15) while maintaining higher firmness and better color retention over the control group. Furthermore, this treatment effectively inhibited electrolyte leakage and malondialdehyde accumulation, enhanced the activities of SOD, POD, CAT, and PAL, maintained chitin content, and downregulated the expression of chitinase and cell wall degradation-related genes. Thus, 5 kJ m⁻² UV-C irradiation is effective in maintaining postharvest quality and extending the storage time of shiitake mushrooms. Full article

Monochamus alternatus, the principal vector of pine wilt disease, poses a serious threat to pine forest ecosystems, and the identification of effective molecular targets is important for the development of environmentally friendly control strategies. In this study, a Group VII chitinase gene, MaCht-2, was identified in M. alternatus, and its developmental expression pattern, RNA interference (RNAi) efficiency, and RNAi-induced phenotypes were investigated using quantitative PCR, dsRNA injection, and transmission electron microscopy. MaCht-2 was highly expressed from the fifth-instar larval stage to the pupal stage, indicating a role in molting and metamorphosis. Silencing of MaCht-2 caused severe developmental defects across multiple life stages, including incomplete ecdysis, pupation failure, adult deformities, impaired locomotion, and high mortality. In third-instar larvae, injection of 5 μg of dsRNA resulted in mortality exceeding 50%. Ultrastructural analysis further showed that MaCht-2 silencing disrupted normal cuticle organization, causing thinning, wrinkling, and disordered lamellar structure. Compared with previously studied chitin-related genes, MaCht-2 produced stronger lethality and more stable RNAi effects. These results indicate that MaCht-2 is essential for normal development of M. alternatus and represents a promising target for RNAi-based pest management. Full article

Volatile organic compounds (VOCs) have garnered substantial research interest in recent years due to their biodegradability, low toxicity, and potent antimicrobial properties against various plant pathogens. As a typical herbivore-induced plant volatile (HIPV) elicited by Nilaparvata lugens (Brown planthopper, BPH), (E)-2-hexenal has been identified as a promising natural antimicrobial agent. In this study, we investigated the protective potential of (E)-2-hexenal against Rhizoctonia solani (R. solani) in rice, focusing on both its direct antifungal activity and host-mediated defense mechanisms. In vitro antifungal assays demonstrated that treatment with 100 μL/mL (E)-2-hexenal resulted in a 91.07% inhibition of R. solani mycelial growth after 48 h. Scanning electron microscopy (SEM) observation and chitinase activity analysis revealed that (E)-2-hexenal suppressed fungal growth by disrupting the structural integrity of the pathogen cell wall. Furthermore, 100 μL/mL (E)-2-hexenal effectively conferred protection to detached rice leaves. Whole-plant inoculation assays confirmed that (E)-2-hexenal pretreatment significantly alleviated disease symptoms and triggered systemic resistance in rice plants. Physiological and biochemical analyses showed that (E)-2-hexenal treatment enhanced the activities of defense-related enzymes, elevated hydrogen peroxide (H₂O₂) levels, and promoted the accumulation of defensive metabolites in rice leaves. HPLC-MS quantification further revealed significant increases in the endogenous levels of jasmonic acid (JA) and salicylic acid (SA). Transcriptomic KEGG pathway enrichment analysis indicated that differentially expressed genes (DEGs) were mainly involved in alpha-linolenic acid metabolism, diterpenoid biosynthesis, phenylpropanoid biosynthesis, plant–pathogen interaction, and plant hormone signal transduction. Collectively, these results suggest that (E)-2-hexenal enhances rice resistance to sheath blight disease via a dual-action mechanism: direct inhibition of fungal development and activation of host immune responses. Our findings highlight the potential application of (E)-2-hexenal and other VOCs in developing eco-friendly strategies for sustainable rice disease management. Full article

Nosema ceranae is a common and highly contagious fungal pathogen that primarily infects the gut of adult honeybees, causing nosemosis. As a chronic disease of the digestive system, it poses a global threat to honeybee health and colony sustainability. This study aimed to investigate the inhibitory effects of different concentrations of Scutellaria baicalensis aqueous extract on N. ceranae in the intestines of infected Apis cerana through feeding experiments. In addition, the therapeutic efficacy of its major active component, baicalin, was evaluated, and its potential molecular mechanisms of action were explored. The results showed that, compared with the control group, administration of S. baicalensis aqueous extract at concentrations of 1 mg/mL, 5 mg/mL, and 10 mg/mL significantly reduced midgut spore loads (p < 0.05). Further experiments showed that a 0.5 mg/mL baicalin sucrose solution, prepared with 0.5% (v/v) DMSO as co-solvent, exhibited optimal solubility and significantly inhibited the proliferation of spores in the honeybee midgut. Transcriptomic analysis of A. cerana revealed varying numbers of significantly differentially expressed genes among the baicalin-treated (HG) group, the co-solvent control (DMSO) group, and the blank control (C) group. Four candidate DEGs associated with the effects of baicalin were further identified, namely LOC108003965, LOC108000905, LOC107996681, and CYP4G11. Gene Ontology enrichment analysis showed that, in the comparison between the HG group and the C group, these DEGs were significantly enriched in six functional categories: iron ion binding, phosphoric ester hydrolase activity, heme binding, tetrapyrrole binding, hydrolase activity (acting on ester bonds), and oxidoreductase activity (acting on paired donors, with incorporation or reduction of molecular oxygen). Collectively, these results demonstrate that S. baicalensis aqueous extract effectively inhibits the proliferation of N. ceranae within the host, and its active component, baicalin, exhibits a similar inhibitory effect. The present study proposes a novel strategy in which baicalin may enhance host endogenous chitinase-related activity to target and disrupt the spore wall, offering a new perspective for the prevention and control of honeybee nosemosis. Full article

Lysobacter antibioticus Hz25 is a novel strain that was isolated from the rhizosphere of the relict endemic plant Hedysarum zundukii Peschkova (Fabaceae), which grows on carbonate soils in the Baikal region of Russia. This work presents the complete genome sequence of Hz25 (5.98 Mb, 66.94% GC), which was obtained using a hybrid assembly method combining Oxford Nanopore and Illumina sequencing. Phylogenetic analysis based on 47 Lysobacter genomes and an average nucleotide identity (ANI) value of 96% confirmed its affiliation with L. antibioticus. A comparative pan-genome analysis with three closely related strains (13-6, 76, and ATCC 29479) identified 554 strain-specific genes. This significant genomic plasticity likely reflects adaptation to the sharply continental climate, high insolation, and low free iron content of the native soil. The genome encodes a comprehensive micropredator arsenal, including: seven chitinase genes (GH18 and GH19 families); bacteriolytic enzymes (Blp, L1, L4, Ami); a complete type III secretion system (T3SS) with predicted effectors; type IV pili (including the PilZ-PilB regulatory complex); and siderophore biosynthesis genes (lysochelin). The genome contains genes ars of an arsenic resistance system, but lacks the ACR3 efflux pump, suggesting that these genes may have alternative functions. Genes involved in calcium homeostasis (Excalibur domain, Na⁺/Ca²⁺ antiporter) were also identified. These features make Hz25 a promising candidate for biocontrol applications in cold climates and metal-contaminated environments. Full article

To identify chitinase genes from the genome of the mycoparasitic Cladosporium sp. strain SYC23, bioinformatical analyses and real-time quantitative PCR (RT-qPCR) were employed to screen mycoparasitism-associated genes at 12, 24, 48, and 72 h post-induction with Aecidium pourthiaea rust spores. A total of eight chitinase genes were identified from SYC23 via bioinformatics analysis and designated CaChi34, CaChi40, CaChi45, CaChi67, CaChi82, CaChi92, CaChi93, and CaChi286 based on sequence and phylogenetic analyses. Analysis of the chitinase protein sequence characteristics revealed molecular weights ranging from 33.86 to 286.03 kDa and theoretical isoelectric points from 4.48 to 7.7. All CaChi genes contained the conserved GH18 domain, and promoter analysis showed that each harbored MYB-binding sites and pathogen-responsive elements. Mycoparasitism-related sequence clustering analysis indicated that the chitinase sequences of SYC23 shared the closest phylogenetic relationship with those from Trichoderma sp. RT-qPCR results following rust spore induction showed that five CaChi genes reached their highest expression levels at 24 h post-induction, CaChi45 was most highly expressed at 72 h post-induction, CaChi93 was continuously upregulated, and CaChi82 was continuously downregulated throughout the induction period. His-tagged recombinant CaChi93 protein was purified from E. coli and characterized. The results demonstrate that the enzymatic activity of CaChi93 was 0.929 U/mg, with optimal reaction conditions at 65 °C and pH 7. Treatment of A. pourthiaea rust spores with the recombinant CaChi93 chitinase confirmed that CaChi93 could effectively dissolve rust spore walls. In conclusion, this study confirms that the mycoparasitic Cladosporium sp. strain SYC23 can secrete chitinase to degrade the rust spore wall and induce spore death, thereby providing novel gene resources and a theoretical basis for the biological control of A. pourthiaea. Full article

The molting of crustaceans is accompanied by exoskeleton reconstruction. To reveal the molecular regulation mechanism of exoskeleton remodeling, the transcriptomic profiles of the exoskeleton across the entire molting process in the red swamp crayfish Procambarus clarkii were investigated by RNA sequencing, yielding a total of 7671 differentially expressed genes (DEGs) across five different molting stages. Notably, the key DEGs were those related to cuticular exoskeleton synthesis (cuticular proteins), degradation (chitinase 2, chitinase 10) and hardening (chitin deacetylase 1), and their expression abundance varied by 10-fold or greater across the molting cycle. Analysis of Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) showed that significantly enriched pathways included the structural constituents of the cuticle, structural molecule activity, chitin binding of chitin metabolism, and hormone biosynthesis. The expression profiles of nine selected molting-related DEGs were further validated via real-time RT-PCR assays. The acquired unique temporal expression patterns involved in exoskeleton remodeling provide a preliminary insight into the regulation of gene expression during the molting cycle in the red swamp crayfish. Full article

Tetranychus urticae is a globally important economic pest mite. Isaria cateniannulata can infect the mite through its conidial penetration of the cuticle, ultimately leading to host mortality; however, the immune mechanisms involving enzyme activity systems and chitinase genes of T. urticae during this process remain unclear. In this study, T. urticae infected with I. cateniannulata was used as experimental material to analyze changes in antioxidant and detoxification enzyme activities during infection. In addition, the expression patterns of six chitinase genes were analyzed, and significantly upregulated genes were selected for bioinformatics analysis and functional verification. The results showed that infection with I. cateniannulata enhanced the activity of defense-related enzymes in T. urticae, with Catalase (CAT) and mixed function oxidase (MFO) playing dominant roles. All six chitinase genes were activated, among which TuCHT7 and TuCHT12 were significantly upregulated at 24 h post-infection, and then TuCHT7 gradually declined. Whereas TuCHT12 maintained a sustained and stable induction pattern, TuCHT10 was suppressed, while the other genes exhibited transient expression. Feeding dsTuCHT12 suppressed the expression of this gene within 72 h, with significant suppression observed at 48 h. At this time, the expression levels of TuCHT8, TuCHT9 and TuCHT10 genes were activated, whereas TuCHT7 and TuCHT11 were suppressed. The combined application of dsCHT12 and I. cateniannulata increased the mortality of T. urticae by 3.19-fold and reduced egg production by 52.8%. This study preliminarily revealed the defense response mechanism of T. urticae against I. cateniannulata infection and provides a theoretical basis for eco-friendly pest control based on the combined application of RNAi and arthropodpathogenic fungi. Full article

Autism spectrum disorder (ASD) is a heterogeneous neurological condition with an unclear etiology and pathogenesis. In recent years, studies have identified changes in lipid metabolism, inflammation, mitochondrial dysfunction, and mitophagy in patients with ASD. However, the specific interactions between these molecular signatures and their clinical applications in ASD remain largely unexplored. The aim of our study is to search for correlations between changes in gene and miRNA expression and the clinical characteristics of ASD. The investigation included a cohort of children with idiopathic ASD and healthy controls (HC). Diagnosis was established based on ADOS assessment (autism diagnostic observation schedule). Gene expression levels of sphingomyelin phosphodiesterases (SMPD1 and 5), ceramide synthases (CerS1 and 6), cyclooxygenase-2 (COX2), chitinase-3-like protein 1 (YKL40), and lysosome-associated membrane proteins 1 and 2 (LAMP1 and 2) were assessed using qPCR. The TaqMan assay was used for the quantification of miR-143-3p and miR-181a-5p. Our findings provide novel data on altered expression profiles of molecules related to lipid metabolism and LAMP1/2 in patients with ASD. We observed increased mRNA levels of CerS1, SMPD5, COX2, YKL40, LAMP1, and LAMP2 and decreased expression of miRNA-181a-5p in ASD patients compared to HC. Additionally, we identified a correlation between CerS1, CerS6, COX2, and miRNA-143-5p with ADOS scores. Multiple regression analysis revealed that 48.0% of the variance in the total ADOS score was explained by the combined effects of COX2, miRNA-143-3p, CerS1, CerS6 and age. These results provide new insights into the molecular alterations associated with ASD and may reinforce future studies aimed at clarifying their functional relevance. Full article

For 12 isolates of Ilyonectria mors-panacis and 4 isolates of Ilyonectria robusta, the number of genes in the secretome showed a negative correlation with growth rates in culture, especially for small secreted non-cysteine-rich and cysteine-rich proteins, and several proteases and lipases, while it was positively correlated with genes for six CAZyme classes/modules and other proteases and lipases. However, this significant correlation with growth rate was influenced by the I. robusta isolates mostly having faster growth rates than the I. mors-panacis isolates on PDA, indicating a species-level difference. The only significant relationship of gene number to virulence was a positive correlation with genes for secreted glycoside hydrolases in families 18 and 78, and this was related to differences between isolates, even if only I. mors-panacis isolates were examined, indicating a difference within species. Glycoside hydrolase family 18 includes chitinase-like proteins, endo-β-N-acetylglucosaminidases, lectins, and xylanase inhibitors, which could help suppress triggered immunity by the host and regulate fungal xylanase activity. Glycoside hydrolase family 78 contain α-L-rhamnosidases that can cleave flavonoid glycosides, saponins, and ginsenosides, which could degrade antimicrobial compounds produced as a host response during infection. These results indicate that the number of certain classes of secreted enzymes could be a factor in both growth rate in culture and virulence. Full article

Background/Objectives: Rheumatoid arthritis is an autoimmune disease that induces joint deformity and disability. There are great expectations for biomarkers that would predict the response to treatment. CHI3L1 and CHI3L2 are chitinase-like proteins (CLPs) which lack enzymatic activity. CHI3L1 is expressed by a variety of cells, while reports on CHI3L2 are limited. The aim of the current study is to evaluate gene and protein CHI3L1 and CHI3L2 expressions before and after treatment of patients with RA and to search for correlations with ultrasonography and conventional laboratory parameters. Methods: Twenty-four newly diagnosed RA patients (19 females and five males) were enrolled in the study. Fourteen patients were treated with tofacitinib (TOFA) and 10 patients with methotrexate (MTX) for twenty-four weeks. Conventional biochemical and immunological markers were examined at the start of the treatment and after the follow-up period. The activity of RA was assessed via the Disease Activity Score 28 (DAS28). Gene expression and protein analysis were performed. Results: Ultrasonographic and clinical laboratory parameters showed improvement after therapy in both groups. A decrease in plasma levels of CHI3L1 (p = 0.04 *) and CHI3L2 (p = 0.03 *) were found after treatment with TOFA. No changes in either protein level were detected after MTX therapy, nor were any differences discovered in the gene expression of CLPs after treatment with both therapeutics. Strong correlations between CRP, GUS7 and CLPs were also established. Conclusions: The similar dynamics of CLPs expression in naïve RA patients and their distinct interplay with disease-related parameters after therapy suggest that both proteins may display different functions in RA pathophysiology. Full article

Fusarium oxysporum-induced soft rot severely threatens postharvest pitaya quality and storage life, and while vanillin shows promise in the disease management, its mechanisms for controlling pitaya decay remain incompletely understood. In this study, we systematically investigated the molecular mechanism by which vanillin inhibits soft rot in postharvest pitaya, employing physiological and biochemical characterization, bioinformatics analysis, and molecular biology techniques. Compared with control fruit on 10 d, vanillin treatment significantly reduced disease index and lesion area by 27.12% and 67.43%, respectively. Meanwhile, vanillin treatment delayed the degradation of total soluble solids (TSSs) and titratable acidity (TA) and promoted the accumulation of total phenolics and flavonoids. Additionally, vanillin enhanced the activities of defense-related enzymes, such as catalase (CAT), superoxide dismutase (SOD), phenylalanine ammonia-lyase (PAL), β-1,3-glucanase (GLU), chitinase (CHI), peroxidase (POD) and polyphenol oxidase (PPO), and increased antioxidant capacity, as evidenced by increased DPPH radical scavenging capacity and ascorbic acid content. This resulted in reduced oxidative damage, as indicated by decreased levels of malondialdehyde (MDA), H₂O₂ and O₂^•−. Yeast one-hybrid (Y1H), dual-luciferase reporter (DLR) and subcellular localization revealed that HuTGA1, a nuclear-localized transcriptional activator, specifically bound to the as-1 cis-acting element and activated expression of HuNPR1 and HuNPR5-1. Transient overexpression of HuTGA1 reduced reactive oxygen species (ROS) accumulation and upregulated related genes. These findings suggest that vanillin treatment might enhance pitaya resistance by activating the HuTGA1-HuNPR signaling module, providing insights into the molecular mechanisms underlying vanillin-induced resistance. Full article

Climate change and global warming are deeply impacting natural foraging dependent upon rain fall. To understand how xerophytes cope with these dramatic changes, comparative transcriptomic profiling of Atriplex halimus and Atriplex leucoclada was investigated under drought stress. The data revealed both shared and species-specific adaptive mechanisms. Differentially expressed genes (DEGs) clustered into major conserved gene families, including stress signaling, transcriptional regulation, antioxidant defense, metabolism, transport, and hormone signaling. In A. halimus, drought tolerance was characterized by strong transcriptional regulation, redox balance, and energy homeostasis, highlighted by the up-regulation of WRKY, MYB, and SET-domain transcription factors, calcium transporters, SnRK1 kinases, and stress-protective proteins such as HSPs and LEAs. On the other hand, A. leucoclada exhibited broader signaling flexibility and structural reinforcement through enrichment of MAPKs, CDPKs, 14-3-3 proteins, and cell wall-modifying enzymes (XTHs, expansins, chitinase-like proteins), as well as high expression of transporters and hormone-responsive genes. Such patterns indicated distinct drought adaptation strategies: A. halimus relied on rapid transcriptional and redox adjustments suited for fluctuating moisture regimes, while A. leucoclada employed multi-layered, constitutive defenses for persistent arid conditions. Together, these results elucidate complementary molecular strategies enabling ecological divergence and drought resilience among closely related halophytes. Full article

Pyrenophora tritici-repentis (Ptr), the causal agent of tan spot, is a necrotrophic fungus that represents a significant threat to wheat production worldwide. The development of resistant cultivars is limited by an incomplete understanding of wheat defence responses against Ptr. Here, weighted gene co-expression network analysis (WGCNA) was applied to RNA-seq data from resistant (Robigus) and susceptible (Hereward) wheat lines before and after Ptr infection to identify coordinated host responses. Eight co-expression modules were identified, three of which were linked to either resistance, susceptibility, or Ptr infection. The resistance-associated module was enriched with chloroplast ribosomal machinery genes (e.g., 50S ribosome-binding GTPase, L28, L6), and transcriptional regulators. This suggested that maintaining chloroplast function, coupled with large-scale transcriptional reprogramming, was important for resistance. The susceptibility-associated module indicated the high expression of post-transcriptional modifiers, including SGS3, RBX1, and SENPs. The Ptr-responsive module showed common responses in both genotypes and included several defence-related genes (nucleotide-binding domain leucine-rich repeat R-genes [NLRs], chitinases, beta-1,3-glucanases) and metabolic pathways, such as phenylpropanoid biosynthesis and nitrogen metabolism (phenylpropanoid ammonia lyase [PAL], cytochrome P450s, glutamine synthase, and ammonium transporters). These results define distinct and shared molecular networks that are linked to resistance and susceptibility, providing valuable candidate genes for functional validation that could ultimately be exploited to enhance wheat resilience against necrotrophic fungal pathogens. Full article