Conformational landscape and pathway of disulfide bond reduction of human alpha defensin.

ABSTRACT: Human alpha defensins are a class of antimicrobial peptides with additional antiviral activity. Such antimicrobial peptides constitute a major part of mammalian innate immunity. Alpha defensins contain six cysteines, which form three well defined disulfide bridges under oxidizing conditions. Residues C3-C31, C5-C20, and C10-C30 form disulfide pairs in the native structure of the peptide. The major tissue in which HD5 is expressed is the crypt of the small intestine, an anaerobic niche that should allow for substantial pools of both oxidized and (partly) reduced HD5. We used ion mobility coupled to mass spectrometry to track the structural changes in HD5 upon disulfide bond reduction. We found evidence of stepwise unfolding of HD5 with sequential reduction of the three disulfide bonds. Alky

SUBMITTER: Snijder J 

PROVIDER: S-EPMC4534177 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature