Crystal structure of the periplasmic disulfide-bond isomerase DsbC from Salmonella enterica serovar Typhimurium and the mechanistic implications.

摘要: The disulfide-bond isomerase DsbC plays a crucial role in the folding of bacterial proteins periplasmic space. has V-shaped dimeric structure with two domains, and Cys98 C-terminal domain attacks inappropriate disulfide bonds substrate due to its high nucleophilic activity. In this article, we present crystal from Salmonella enterica serovar Typhimurium. We evaluated conserved residues Asp95 Arg125, which are located close Cys98. mutation or Arg125 abolished activity an vitro assay using protein substrate, R125A significantly reduced chaperone for RNase I vivo. Furthermore, comparative analysis suggested that conformation varies depending on packing protein-protein interactions. Based these findings, suggest modulate pKa during catalysis.