Interchangeable modules in bacterial thiol-disulfide exchange pathways.
Thiol-disulfide oxidoreductases (TDORs) catalyze thiol-disulfide exchange reactions that are crucial for protein activity and stability. Specifically, they can function as thiol oxidases, disulfide reductases or disulfide isomerases. The generally established view is that particular TDORs act unidirectionally within a fixed cascade of specific, sequentially arranged reactions. However, recent studies on both Gram-negative and Gram-positive bacteria imply that this view needs to be expanded, at least for thiol-disulfide exchanges in proteins that are exported from the cytoplasm. Here, we present our opinion that various TDORs can function as interchangeable modules in different thiol-disulfide exchange pathways. Such TDOR modules, thus, fulfil important functions in generating the diversity in activity and specificity that is needed in productive extracytoplasmic thiol-disulfide exchange.
Kouwen
Thijs R H M
TR
Department of Medical Microbiology, University Medical Center Groningen and University of Groningen, Hanzeplein 1, P.O. box 30001, 9700 RB Groningen, the Netherlands.
van Dijl
Jan Maarten
JM
D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004220:Disulfides / Q000737:chemistry / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D010084:Oxidation-Reduction; D011490:Protein Disulfide Reductase (Glutathione) / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019704:Protein Disulfide-Isomerases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000378:metabolism*
D001426:Bacterial Proteins; D004220:Disulfides; C079503:DsbB protein, Bacteria; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D013438:Sulfhydryl Compounds; D011490:Protein Disulfide Reductase (Glutathione); D019704:Protein Disulfide-Isomerases; C526648:dsbA protein, E coli