Positive Charges Are Important for the SOS Constitutive Phenotype in recA730 and recA1202 Mutants of Escherichia coli K-12.

ABSTRACT: In Escherichia coli K-12, RecA binds to single-strand DNA (ssDNA) created by DNA damage to form a protein-DNA helical filament that serves to catalyze LexA autoproteolysis, which induces the SOS response. The SOS constitutive (SOS^C) mutations recA730(E38K) and recA1202(Q184K) are both on the outside of the RecA filament, opposite to the face that binds DNA. recA730(E38K) is also able to suppress the UV sensitivity caused by recF mutations. Both SOS^C expression and recF suppression are thought to be due to RecA730's ability to compete better for ssDNA coated with ssDNA-binding protein than the wild type. We tested whether other positively charged residues at these two positions would lead to SOS^C expression and recF

SUBMITTER: Van Alstine S 

PROVIDER: S-EPMC9112999 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature