RRC ID 76860
Author Nohmi T, Yamada M, Matsui K, Watanabe M, Sofuni T.
Title Specific disruption of samAB genes in a 60-megadalton cryptic plasmid of Salmonella typhimurium.
Journal Mutat Res
Abstract The expression of umuDC operon is required for UV and most chemical mutagenesis in Escherichia coli. The closely related species Salmonella typhimurium has two sets of umuDC-like operons, i.e., umuDCST in the chromosome and samAB in a 60-megadalton cryptic plasmid. In this study, we specifically disrupted the samAB genes to investigate their exact roles in UV mutagenesis in S. typhimurium. The specific gene disruption was carried out by the preligation method. Deletion of samAB did not lower the UV mutability of S. typhimurium TA2659 but rather increased the UV mutability about twofold. The samAB-umuDCST double deletion mutant as well as the umuDCST deletion mutant was UV nonmutable. These results suggest that the samAB genes do not considerably contribute to the UV mutability of S. typhimurium and raise the question of why such quiet umuDC-like genes are present in the cryptic plasmid of S. typhimurium.
Volume 329(1)
Pages 1-9
Published 1995-6-1
DOI 10.1016/0027-5107(95)00027-g
PII 002751079500027G
PMID 7770072
MeSH Blotting, Southern Chloramphenicol O-Acetyltransferase / genetics Cloning, Molecular Gene Deletion Genes, Bacterial* Mutagenesis Operon Plasmids Radiation Tolerance / genetics* Restriction Mapping Salmonella typhimurium / genetics Salmonella typhimurium / radiation effects* Ultraviolet Rays*
IF 2.463
Prokaryotes E. coli ME10045 ME10046 ME10047