Exopolysaccharide defects cause hyper-thymineless death in Escherichia coli via massive loss of chromosomal DNA and cell lysis.

ABSTRACT: Thymineless death in Escherichia coli thyA mutants growing in the absence of thymidine (dT) is preceded by a substantial resistance phase, during which the culture titer remains static, as if the chromosome has to accumulate damage before ultimately failing. Significant chromosomal replication and fragmentation during the resistance phase could provide appropriate sources of this damage. Alternatively, the initial chromosomal replication in thymine (T)-starved cells could reflect a considerable endogenous dT source, making the resistance phase a delay of acute starvation, rather than an integral part of thymineless death. Here we identify such a low-molecular-weight (LMW)-dT source as mostly dTDP-glucose and its derivatives, used to synthesize enterobacterial common antigen (ECA). T

SUBMITTER: Rao TVP 

PROVIDER: S-EPMC7777189 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature