Homology modeling of N. Meningitidisis OxyR

Author: Shorena Ukleba
Co-authors: Shorena Ukleba
Keywords: OxyR, N. Meningitidisis, oxidative stress, transcriptional regulators
Annotation:

All organisms are under of influence of an oxidative stress. On intracellular level reactive oxygen radicals cause damage of oxidative homeostasis that may induce cell damage and degenerative diseases. Therefore organisms cultivated adaptation mechanisms by evolution for neutralizing reactive radicals. Cellular membrane has special proteins that activate to neutralized reactive radicals. Special transcriptional regulators synthesize these proteins. One of those regulators is OxyR, which has two domains: N-terminal (DBD) and C-terminal (RD). Regulatory domain contains the redox sensitive cysteines. Oxidation of the active sites of these cysteines causes activation of antioxidant’s synthesis. OxyR transcriptionally regulates oxidative stress response through a reversibly reducible cysteine disulfide biosensor of cellular redox status. It is known that in E. coli OxyR C199–C208 disulfide loop formation causes change in configuration of the dimer. We made homology modeling of oxidized N.M OxyR based on E. coli, P. gingivalis and N. Meningitidis OxyR crystal structures. Comparison of the modeled oxidized NM OxyR with reduced OxyR revealed that, disulfide loop formation does not trigger change in configuration of the dimer, because it has 5 residual insert at 215 position in contrast of E.coli OxyR.