Biomaterial Database

Mutator gene studies in Escherichia coli: the mutS gene. 1972

E C Cox, and G E Degnen, and M L Scheppe

We report here on a study of a mutator gene (mutS) that causes transition mutations in Escherichia coli. We have used the trpA system to show that A:T-->G:C and G:C-->A:T transitions occur. Not all A:T pairs are equally susceptible to mutS action however, since the A:T pair at the trpA223 site reverts at a frequency similar to, if not identical with, the frequency in a mut(+) background. Presumably this is a consequence of neighboring bases, because other A:T pairs are reverted by mutS in the same gene; and an A:T pair in the lac operon is reverted at two widely separated points on the chromosome, and in two orientations relative to the trp sense strand. In addition, we have shown that the mutS1 allele is recessive to wild type, and trans active.

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D009876	Operon	In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.	Operons
D002876	Chromosomes, Bacterial	Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.	Bacterial Chromosome,Bacterial Chromosomes,Chromosome, Bacterial
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D005075	Biological Evolution	The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.	Evolution, Biological
D005796	Genes	A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.	Cistron,Gene,Genetic Materials,Cistrons,Genetic Material,Material, Genetic,Materials, Genetic
D005808	Genes, Recessive	Genes that influence the PHENOTYPE only in the homozygous state.	Conditions, Recessive Genetic,Genetic Conditions, Recessive,Recessive Genetic Conditions,Condition, Recessive Genetic,Gene, Recessive,Genetic Condition, Recessive,Recessive Gene,Recessive Genes,Recessive Genetic Condition
D005815	Genetic Code	The meaning ascribed to the BASE SEQUENCE with respect to how it is translated into AMINO ACID SEQUENCE. The start, stop, and order of amino acids of a protein is specified by consecutive triplets of nucleotides called codons (CODON).	Code, Genetic,Codes, Genetic,Genetic Codes
D000483	Alleles	Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.	Allelomorphs,Allele,Allelomorph