Molecular bases for strong phenotypic effects of single synonymous codon substitutions in the E. coli ccdB toxin gene.

ABSTRACT:

Background

Single synonymous codon mutations typically have only minor or no effects on gene function. Here, we estimate the effects on cell growth of ~ 200 single synonymous codon mutations in an operonic context by mutating almost all positions of ccdB, the 101-residue long cytotoxin of the ccdAB Toxin-Antitoxin (TA) operon to most degenerate codons. Phenotypes were assayed by transforming the mutant library into CcdB sensitive and resistant E. coli strains, isolating plasmid pools, and subjecting them to deep sequencing. Since autoregulation is a hallmark of TA operons, phenotypes obtained for ccdB synonymous mutants after transformation in a RelE toxin reporter strain followed by deep sequencing provided information on the amount of CcdAB complex formed.

Results

Synonymo

SUBMITTER: Bajaj P 

PROVIDER: S-EPMC10694988 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature