ANTH 210 Lecture Notes - Lecture 8: Conformational Change, Autophosphorylation, Translocon
Document Summary
Asparagine any amino acid followed by a glutamine. Lecture 8: membranes iv (chapter 6), january 24th 2018. Folding is necessary to exit er to the secretory pathway. Er lumen is an oxidizing environment , but spontaneous disulfide formation is inefficient and/or incorrect for folding. Favours formation of disulfide bonds which is an oxidizing reaction. Have two reactive cys residues close together, can oxidize substrate. First function is that oxidized pdi catalyzes formation of disulfide bonds in substrate. Pdi becomes reduced because we transferred oxidizing equivalent from pdi to substrate. Second function if that reduced pdi aids rearrangements of disulfide bonds during folding. The first disulfides to form may not be correct for the native state. May have wrong disulfide bonds and thus disulfide bonds need to be moved. In both reactions, pdi forms mixed disulfide intermediates with substrate. Pdi becomes reduced after oxidizing the substrate. Pdi is oxidized again by ero1 proteins which starts in oxidized form with cofactor fad.