title: Nitrosative Stress Response in Vibrio cholerae: Role of S-Nitrosoglutathione Reductase.
abstract: Vibrio cholerae, the causative agent of cholera, poses serious threats to humans worldwide. V. cholerae faces host inflammatory response and encounters nitrosative stress before establishing successful colonization. It is not clear how V. cholerae combats nitric oxide and reactive nitrogen species. In the present study, we used three clinical strains of V. cholerae and tested their nitrosative stress response pattern towards sodium nitroprusside (SNP) and S-Nitrosoglutathione (GSNO). Among them, V. cholerae, belonging to both O1 and O139 serotypes, showed moderate resistance to SNP and GSNO. However, a V. cholerae strain belonging to non O1 and non O139 showed sensitivity to SNP but resistance towards GSNO. Reduced glutathione and glutathione reductase play a significant role to combat nitrosative stress in V. cholerae. This is the first report where we show the presence of GSNO reductase activity in V. cholerae and that it plays an important role to detoxify S-Nitrosoglutathione. GSNO reductase activity of V. cholerae was regulated by posttranslational modification through S-nitrosylation under in vitro conditions which could be reversed by dithiothreitol (DTT). In addition, we show that biofilm formation remained unaffected under nitrosative stress in V. cholerae.
authors.affiliation: Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, West Bengal, 700019, India.
authors.forename: Sourav Kumar
authors.initials: SK
authors.lastname: Patra
authors.affiliation: Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, West Bengal, 700019, India.
authors.forename: Prasanta Kumar
authors.initials: PK
authors.lastname: Bag
authors.affiliation: Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, West Bengal, 700019, India. sgbioc@caluniv.ac.in.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Ghosh
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D006801:Humans; D009599:Nitroprusside / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D026422:S-Nitrosoglutathione / Q000494:pharmacology*; D014734:Vibrio cholerae / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D009599:Nitroprusside; D026422:S-Nitrosoglutathione; D000445:Aldehyde Oxidoreductases; C087006:formaldehyde dehydrogenase, glutathione-independent
keywords: GSNO reductase; Nitric oxide; Nitrosative stress; S-nitrosylation; Vibrio cholerae