Biomaterial Database

Synergism of Dam, MutH, and MutS in methylation-directed mismatch repair in Escherichia coli. 2017

Changkun Hu, and Yunqi Zhao, and Huiyun Sun, and Yixin Yang

Department of Biological Sciences, Emporia State University, 1 Kellogg Circle, Emporia, KS 66801, USA.

DNA mismatch repair (MMR) is a critical mutation surveillance system for recognizing and repairing erroneous insertion, deletion, and disincorporation of base. Major components of mismatch repair system consist of MutH, MutL, and MutS. Dam methylates adenine to distinguish newly synthesized daughter strands from the parent strands. Employing a tyrosine-auxotrophic E. coli FX-11 strain, the mutation frequency can be determined by the number of tyrosine revertants and the cell viability of FX-11 with deficiencies in dam and mismatch repair proteins. This study showed that mutS defect produced a higher mutation frequency than mutH did. Interestingly, double defects in dam and mutS synergistically produced a dramatically higher spontaneous mutation frequency than the summation of mutation frequencies of FX-11 strains with individual deficiency of dam or mutS, suggesting that Dam may work with MutHL to partially accomplish the task of recognizing the mismatch sites to retain partial mismatch repair capacity.

UI	MeSH Term	Description	Entries
D004268	DNA-Binding Proteins	Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.	DNA Helix Destabilizing Proteins,DNA-Binding Protein,Single-Stranded DNA Binding Proteins,DNA Binding Protein,DNA Single-Stranded Binding Protein,SS DNA BP,Single-Stranded DNA-Binding Protein,Binding Protein, DNA,DNA Binding Proteins,DNA Single Stranded Binding Protein,DNA-Binding Protein, Single-Stranded,Protein, DNA-Binding,Single Stranded DNA Binding Protein,Single Stranded DNA Binding Proteins
D004706	Endodeoxyribonucleases	A group of enzymes catalyzing the endonucleolytic cleavage of DNA. They include members of EC 3.1.21.-, EC 3.1.22.-, EC 3.1.23.- (DNA RESTRICTION ENZYMES), EC 3.1.24.- (DNA RESTRICTION ENZYMES), and EC 3.1.25.-.
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
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial
D015254	DNA Modification Methylases	Enzymes that are part of the restriction-modification systems. They are responsible for producing a species-characteristic methylation pattern, on either adenine or cytosine residues, in a specific short base sequence in the host cell's own DNA. This methylated sequence will occur many times in the host-cell DNA and remain intact for the lifetime of the cell. Any DNA from another species which gains entry into a living cell and lacks the characteristic methylation pattern will be recognized by the restriction endonucleases of similar specificity and destroyed by cleavage. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms.	DNA Modification Methyltransferases,Modification Methylases,Methylases, DNA Modification,Methylases, Modification,Methyltransferases, DNA Modification,Modification Methylases, DNA,Modification Methyltransferases, DNA
D015964	Gene Expression Regulation, Bacterial	Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.	Bacterial Gene Expression Regulation,Regulation of Gene Expression, Bacterial,Regulation, Gene Expression, Bacterial
D016296	Mutagenesis	Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.	Mutageneses
D045643	DNA Repair Enzymes	Enzymes that are involved in the reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule, which contained damaged regions.	DNA Repair Enzyme,Enzyme, DNA Repair,Enzymes, DNA Repair,Repair Enzyme, DNA,Repair Enzymes, DNA
D051719	MutS DNA Mismatch-Binding Protein	A methyl-directed mismatch DNA REPAIR protein that has weak ATPASE activity. MutS was originally described in ESCHERICHIA COLI.	DNA Mismatch Repair Protein MutS,MutS DNA Mismatch Binding Protein
D053843	DNA Mismatch Repair	A DNA repair pathway involved in correction of errors introduced during DNA replication when an incorrect base, which cannot form hydrogen bonds with the corresponding base in the parent strand, is incorporated into the daughter strand. Excinucleases recognize the BASE PAIR MISMATCH and cause a segment of polynucleotide chain to be excised from the daughter strand, thereby removing the mismatched base. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)	Mismatch Repair,Mismatch Repair, DNA,Repair, DNA Mismatch,Repair, Mismatch