Open AccessMutations in dsbA and dsbB , but not dsbC , lead to an enhanced sensitivity of Escherichia coli to Hg 2+ and Cd 2+
Author(s) -
Stafford Simon J,
Humphreys David P,
Lund Peter A
Publication year - 1999
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1999.tb13566.x
Subject(s) - dsba , periplasmic space , escherichia coli , protein disulfide isomerase , mutant , gene , chemistry , isomerase , mutation , biology , genetics , biochemistry , microbiology and biotechnology , enzyme
The Dsb proteins are involved in disulfide bond formation, reduction and isomerisation in a number of Gram‐negative bacteria. Mutations in dsbA or dsbB , but not dsbC , increase the proportion of proteins with free thiols in the periplasm compared to wild‐type. We investigated the effects of mutations in these genes on the bacterial resistance to mercuric and cadmium salts. Mutations in genes involved primarily in disulfide formation ( dsbA and dsbB ) generally enhanced the sensitivity to Hg 2+ and Cd 2+ while a mutation of the dsbC gene (primarily an isomerase of disulfide bonds) had no effect. Mutations of the dsb genes had no effect on the expression of the mercury‐resistance determinants of the transposon Tn 501.