Open AccessEscherichia coli DNA ligase B may mitigate damage from oxidative stress
Author(s) -
Truston J. Bodine,
Michael A. Evangelista,
Huan Ting Chang,
Christopher A. Ayoub,
Buck S. Samuel,
Richard Sucgang,
Lynn Zechiedrich
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0180800
Subject(s) - dna ligase , biology , ubiquitin ligase , escherichia coli , dna mismatch repair , dna repair , dna replication , microbiology and biotechnology , genetics , dna , gene , ubiquitin
Escherichia coli encodes two DNA ligases, ligase A, which is essential under normal laboratory growth conditions, and ligase B, which is not. Here we report potential functions of ligase B. We found that across the entire Enterobacteriaceae family, ligase B is highly conserved in both amino acid identity and synteny with genes associated with oxidative stress. Deletion of ligB sensitized E . coli to specific DNA damaging agents and antibiotics resulted in a weak mutator phenotype, and decreased biofilm formation. Overexpression of ligB caused a dramatic extension of lag phase that eventually resumed normal growth. The ligase function of ligase B was not required to mediate the extended lag phase, as overexpression of a ligase-deficient ligB mutant also blocked growth. Overexpression of ligB during logarithmic growth caused an immediate block of cell growth and DNA replication, and death of about half of cells. These data support a potential role for ligase B in the base excision repair pathway or the mismatch repair pathway.