**5. Conclusions**

Together, our data show that NO resistance in *L. braziliensis* involves rapid remodeling of the parasites' proteome, resulting in increased protein content as well as in increased GSH metabolism, higher levels of glucose consumption, elevated abundance of PPP enzymes, and lower mitochondrial respiration, all of which can contribute to thiol and NADPH pool maintenance in these parasites, enabling them to successfully colonize and persist in host cells.

**Supplementary Materials:** The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/antiox11020277/s1, Figure S1: Growth curves of *L. braziliensis* strains; Figure S2: Volcano plot representation of differences in protein concentration between NOresistant and NO-susceptible *L. braziliensis* strains; Figure S3: Overview of the glycolysis pathway in *L. braziliensis* and identified enzymes; Figure S4: Overview of the pentose phosphate pathway (PPP) in *L. braziliensis* and identified enzymes; Table S1: Protein Groups identified; Table S2: Summary of general information about the proteomes of *Leishmania braziliensis* strains resistant or susceptible to NO; Table S3: Statistical differences among groups.

**Author Contributions:** Conceptualization, P.C. and R.M.-B.; methodology, J.R.W.; validation, P.C., N.P., R.M.-B. and A.C.B.; formal analysis, N.P., A.C.B., J.R.W., G.D.-L., L.S.-V., J.B.d.J., E.C., G.P., R.M.-B. and P.C.; investigation, N.P., A.C.B., J.R.W., G.D.-L., L.S.-V., R.P.d.A., G.P., J.B.d.J. and P.C.; resources, R.P.d.A., J.R.W., E.C., J.B.d.J., R.M.-B. and P.C.; writing—original draft preparation, P.C., N.P. and A.C.B.; writing—review and editing, P.C., R.M.-B.; N.P., A.C.B., J.R.W., E.C., J.B.d.J., G.P.; supervision, P.C. and R.M.-B.; project administration, P.C.; funding acquisition, P.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by Conselho Nacional De Desenvolvimento Científico E Tecnológico—CNPq (P.C.—Universal grant No. 423300/2018-0); FIOCRUZ (P.C., N.P., L.S.-V, E.C., G.P.—PAEF grant No. IOC-023-FIO-18-2-63); Fundação De Amparo À Pesquisa Do Estado De Rio De Janeiro—FAPERJ (P.C.—JCNE E-26/203.253/2017, N.P.—TCT No. E-26/202.464/2017); Max-Planck Society For The Advancement Of Science; and Coordenação De Aperfeiçoamento De Pessoal De Nível Superior—CAPES, Brasil—Finance Code 001 (P.C.—Process No. 88887.374332/2019-00). G.P. was a CAPES fellow of the Visitant Professor Program (Process No. 0344141). P.C. and R.P.d.A. are CNPq PQ-fellows (PQ-P.C. Process No. 305796/2017-8 and 312573/2020-0, R.P.d.A.—PQ Process No. 309776/2018-0).

**Institutional Review Board Statement:** All the protocols were carried out in accordance with the recommendations of the Guide for the Care and Use of Laboratory Animals, according to resolution 196/96 of the National Council for Animal Experimentation—COBEA (https://sbcal.org.br/ (accessed on 2 March 2020)). The animal study protocol was approved by the Animal Use Ethics Committee of INSTITUTO OSWALDO CRUZ-IOC/Fiocruz (L-005/2017; 07/02/2017). According to the Brazilian Law of Biodiversity, this study was registered at SisGen (AA2236F).

**Data Availability Statement:** The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE [31] partner repository with the dataset identifier PXD029462.

**Acknowledgments:** The authors are grateful to Matthias Mann for continuous support. We thank Katharina Zettl for technical help with mass spectrometric measurements, and Rosane Temporal, quality manager of LPL-FIOCRUZ-RJ and all the staff of CLIOC, for technical assistance and quality advice.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.
