We used the lacI system of Escherichia coli to examine the distribution of base substitution
mutations occurring spontaneously in different mismatch-repair-deficient strains. The …

We have determined the DNA sequence changes in 487 spontaneous mutations in the N-
terminal part of the lacI gene in mutH, mutL, and mutS strains of Escherichia coli. These …

To gain more detailed insight into the nature and mechanisms of spontaneous mutations, we
undertook a DNA sequence analysis of a large collection of spontaneous mutations in the N …

Over the course of thousands of generations of growth in a glucose-limited environment, 3 of
12 experimental populations of Escherichia coli spontaneously and independently evolved …

To investigate the mechanisms of spontaneous mutation in the Escherichia coli mutD5
mutator strain, 502 mutations generated in this strain in the N-terminal part of the lacI gene …

Our approach to the isolation of DNA mismatch-correction-deficient mutants was based
upon the isolation of 2-aminopurine-resistant second-site revertants of Escherichia coli dam …

The Dam-directed post-replicatve mismatch repair system of Escherichia coli removes base
pair mismatches from DNA. The products of the mutH, mutL and mutS genes, among others …

Strains of Escherichia coli carrying the mutY mutation lack a mismatch correction
glycosylase that removes adenines from various mismatch situations. In growing bacteria, 8 …

The mutational spectrum at the lacI locus in a dam-4 strain of Escherichia coli was
examined. The observed 20-fold increase in spontaneous mutagenesis in a dam− strain …

Excessive recombination between repeated, interspersed, and diverged DNA sequences is
a potential source of genomic instability. We have investigated the possibility that a …