Topoisomerase mutations affect the relative abundance of many Escherichia coli proteins.
The relative abundance of 88 proteins was measured in extracts from three strains of Escherichia coli K-12 that are isogenic except for the topA and gyrB genes. Mutations in these genes slightly raise or lower, respectively, steady-state DNA supercoiling levels but have little effect on growth rate. Altered protein abundances were observed in the mutant strains relative to wild type. Many proteins exhibited minimum abundance at wild-type supercoiling levels, and other proteins exhibited maximal abundance at relaxed levels. A smaller number showed maximal abundance at elevated levels of supercoiling. These data suggest that small, non-lethal changes in DNA supercoiling can have widespread effects on patterns of gene expression.
Department of Biology, University of North Carolina at Charlotte 28223.
T R
TR
Steck
R J
RJ
Franco
J Y
JY
Wang
K
K
Drlica
D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics*; D004264:DNA Topoisomerases, Type I / Q000235:genetics* / Q000502:physiology; D004250:DNA Topoisomerases, Type II / Q000235:genetics* / Q000502:physiology; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004278:DNA, Superhelical / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D016296:Mutagenesis
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004278:DNA, Superhelical; D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II