Reduction of protein disulfide bonds in an oxidizing environment

FEBS Letters

Majoul, Irina¹  Söling, Hans-Dieter¹  Ferrari, David¹ 

[1] Abteilung Klinische Biochemie, Universität Göttingen, Robert-Kochstr. 40, D-37070 Göttingen, Germany

关键词: Cholera toxin;    Protein disulfide isomerase;    Endoplasmic reticulum;    Glutathione;    Redox state;    Protein disulfide;   

DOI  :  10.1016/S0014-5793(96)01447-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Following retrograde transport to the endoplasmic reticulum (ER) the A-subunit of cholera toxin (CTX-A) is partially cleaved into CTX-A1 and CTX-A2 by reduction of a disulfide bridge [Majoul et al. (1996) J. Cell Biol. 133, 777–789], although the redox state in the ER favors disulfide formation. We show here that the disulfide bridge of CTX-A is cleaved in vitro already at GSH/GSSG ratios between 1 and 3. Protein disulfide isomerase (PDI) exerts only a minor accelerating effect. Various mixed disulfide intermediates (CTX-A1-S-S-CTX-A1; PDI-S-S-A2; PDI-S-S-A1) appear during CTX-A reduction. These results indicate that in the ER protein disulfide formation and protein disulfide reduction can take place simultaneously.

【 授权许可】

Unknown