RRC ID 30127
Author Kogoma T, Barnard KG, Hong X.
Title RecA, Tus protein and constitutive stable DNA replication in Escherichia coli rnhA mutants.
Journal Mol. Gen. Genet.
Abstract Constitutive stable DNA replication (cSDR), which uniquely occurs in Escherichia coli rnhA mutants deficient in ribonuclease HI activity, requires RecA function. The recA428 mutation, which inactivates the recombinase activity but imparts a constitutive coprotease activity, blocks cSDR in rnhA mutants. The result indicates that the recombinase activity of RecA, which promotes homologous pairing and strand exchange, is essential for cSDR. Despite the requirement for RecA recombinase activity, mutations in recB, recD, recJ, ruvA and ruvC neither inhibit nor stimulate cSDR. It was proposed that the property of RecA essential for homologous pairing and strand exchange is uniquely required for initiation of cSDR in rnhA mutants without involving the homologous recombination process. The possibility that RecA protein is necessary to counteract the action of Tus protein, a contra-helicase which stalls replication forks in the ter region of the chromosome, was ruled out because introduction of the tus::kan mutation, which inactivates Tus protein, did not alleviate the RecA requirement for cSDR.
Volume 244(5)
Pages 557-62
Published 1994-9-1
PMID 8078483
MeSH Bacterial Proteins / metabolism Chromosomes, Bacterial DNA Nucleotidyltransferases / metabolism DNA Replication* DNA, Bacterial / chemistry Escherichia coli / enzymology Escherichia coli / genetics* Escherichia coli Proteins* Genes, Bacterial* Mutation Nucleic Acid Conformation Rec A Recombinases / genetics* Rec A Recombinases / metabolism Recombination, Genetic* Ribonuclease H / deficiency
Times Cited 7
Prokaryotes E. coli ME9476 ME9535 ME9517 ME9501 ME9494 ME9497 ME9498 ME9428 ME9396 ME9347 ME9238