Aug 2026· Molecular and Cellular Biology· Vol 46, pp.
1-18
· 0 citations· 45 references
Medicine
TL;DR
It is discovered that dif sequence and XerC/D are essential for cSDR-dependent growth and site-specific recombination mediated by dif-XerC/D is essential for cSDR-dependent growth.
Abstract
Escherichia coli cells can grow in a DnaA- and oriC-independent manner in rnhA-deficient cells that lack the major RNaseH activity. This mode of replication is named cSDR (constitutive stable DNA replication) and is believed to initiate from the sites of RNA-DNA hybrids, although the detailed mechanisms of cSDR are unclear. In this study, we discovered that dif sequence and XerC/D are essential for cSDR-dependent growth. cSDR was observed in either dif or xerC/D mutant cells as efficiently as in the control cells, as measured by the incorporation of [3H]-thymine. However, we found that these mutants accumulate cells with extra DNA contents in the presence of rifampicin and cefalexin, suggesting accumulation of unresolved dimeric or multimeric chromosomes or that of catenated chromosomes due to potential problems in resolution of the replicated chromosomes or in decatenation process. These results indicate that site-specific recombination mediated by dif-XerC/D is essential for cSDR-dependent growth.
ABSTRACT Abortive infection (Abi) systems protect bacterial populations from bacteriophages by triggering growth arrest or cell death in infected cells; however, how Abi effectors are coupled to changes in host DNA replication and repair remains unclear. The widely conserved Hachiman defense system encodes a nuclease (...
Saya Takita, Reoto Moroi, Haruka Terasaki et al.· Journal of Bacteriology· 0 citations
Integrative and conjugative elements (ICEs) are widespread in bacteria and typically confer important phenotypes to their hosts. Following excision from the host chromosome, an ICE can transfer to a new cell through the element-encoded conjugation machinery (a type IV secretion system) to create a transconjugant. Tn916...
Alexa F. S. Gomberg, Alan D. Grossman· bioRxiv· 0 citations
In bacteria, DNA replication and chromosome segregation are tightly coordinated with cell division. The replication run-out method, which combines inhibition of transcription initiation by rifampicin with inhibition of cell division by cephalexin, is widely used to analyse replication dynamics by allowing ongoing...
Iren Grigoryan, Dominika Krawiel, Emma L. Dunbar et al.· BMC Microbiology· 0 citations
ABSTRACT Structural maintenance of chromosomes (SMC) complexes play conserved roles in chromosome organization, segregation, and repair in all domains of life. In Bacillus subtilis, SMC is required for the segregation of newly replicated origins. To investigate whether other proteins function with SMC in this process,...
Ngoc Khanh Lai, Laura C. Lastra, Kehinde O. Adebiyi et al.· Journal of Bacteriology· 0 citations
Stationary-phase cultures contain high abundances of persisters, which are bacterial cells that are hyper-tolerant to antibiotics due to phenotypic reasons. Fluoroquinolones (FQs) are one of the most effective antibiotic classes for the treatment of non-growing bacteria, such as those found in stationary-phase cultures...
Nashaly Soto-Echevarria, Annabel S. Lemma, M. P. Brynildsen· PLoS Genetics· 0 citations
ABSTRACT PA0947 is annotated as an essential hypothetical protein in Pseudomonas aeruginosa and shares substantial sequence identity with the Escherichia coli replication regulator Hda, yet its cellular function and genetic bypass logic in P. aeruginosa have not been experimentally characterized. Here, we constructed a...
