title: Mutational analysis of the oxidoreductase ERp57 reveals the importance of the two central residues in the redox motif.
abstract: The oxidoreductase ERp57 is involved in the formation and breaking of disulfide bonds in assembling proteins within the environment of the endoplasmic reticulum. Site-directed mutants of the redox-active Cys-Gly-His-Cys motif within an isolated ERp57 sub-domain have been studied. Whereas mutation of either cysteine residue abolished reductase activity, substitution of the central residues resulted in retention of partial activity. Alkylation studies indicated that the central residue mutants retained the normal disulfide bond in the motif, whereas this disulfide bond became more resistant to reduction following addition of a third residue into the redox motif, demonstrating an optimum spacing within the redox-active motif of ERp57.
authors.affiliation: Division of Cell Biology and Immunology, University of Dundee, Dundee, DD1 5EH, UK.
authors.forename: Siân M
authors.initials: SM
authors.lastname: Beynon-Jones
authors.forename: Antony N
authors.initials: AN
authors.lastname: Antoniou
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Powis
mesh_terms: D000478:Alkylation; D020816:Amino Acid Motifs; D000818:Animals; D003545:Cysteine; D006360:Heat-Shock Proteins / Q000235:genetics*; D016297:Mutagenesis, Site-Directed; D010084:Oxidation-Reduction; D019704:Protein Disulfide-Isomerases / Q000235:genetics*; D051381:Rats; D011994:Recombinant Proteins
chemical_list: D006360:Heat-Shock Proteins; D011994:Recombinant Proteins; C513196:PDIA3 protein, rat; D019704:Protein Disulfide-Isomerases; D003545:Cysteine