Insufficient levels of the nrdAB-encoded ribonucleotide reductase underlie the severe growth defect of the Δhda E. coli strain.

ABSTRACT: The ATP-bound form of the Escherichia coli DnaA replication initiator protein remodels the chromosomal origin of replication, oriC, to load the replicative helicase. The primary mechanism for regulating the activity of DnaA involves the Hda and β clamp proteins, which act together to dramatically stimulate the intrinsic DNA-dependent ATPase activity of DnaA via a process termed Regulatory Inactivation of DnaA. In addition to hyperinitiation, strains lacking hda function also exhibit cold sensitive growth at 30°C. Strains impaired for the other regulators of initiation (i.e., ΔseqA or ΔdatA) fail to exhibit cold sensitivity. The goal of this study was to gain insight into why loss of hda function impedes growth. We used a genetic approach to isolate 9 suppressors of Δhda cold sensitivity, a

SUBMITTER: Babu VMP 

PROVIDER: S-EPMC5397354 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature