Biomaterial Database

[The repair of UV-induced postreplication DNA gaps in Escherichia coli cells adapted to methylmethane sulfonate and ethylmethane sulfonate]. 1994

V D Zhestianikov, and G E Savel'eva

The survival (only after the adaptation to methylmethane sulfonate, MMS) and repair of DNA postreplication gaps in UV-irradiated Escherichia coli, adapted to MMS (20 mkg/ml for 3 h) and ethylmethane sulfonate (EMS, 100 mkg/ml for 3 h), have been investigated. The survival of MMS-adapted bacteria of wild strains B/r and K12 AB1157 somewhat increased, whereas the survival of AB1886 uvrA mutant, which unlike the wild type bacteria is unable to excise cyclobutane pyrimidine dimers, was seen to decrease. The repair of postreplicative gaps in MMS-adapted bacteria correlates qualitatively with changes in survival: in B/r and AB1157 strains the repair is somewhat more effective (10-15%), while in AB1886 uvrA mutant significantly slower (near 30%) than in non-adapted bacteria. Similar changes of postreplicative repair (PRR) of DNA are observed in AB1157 and AB1886 uvrA strains adapted to EMS. It is suggested that the decreased efficiency of PRR in bacteria AB1886 uvrA, adapted to alkylating agent, may be due to the interference between the two inducible repair processes: adaptive response and SOS response. The latter process is involved in the repair of some part of postreplicative gaps of DNA. Different results of PRR of DNA in bacteria of wild types, adapted to MMS and EMS, may be associated with the intrinsic PRR in uvr+ strains. Due to this process in uvr+ bacteria SOS component of PRR of DNA is not formed. It is suggested that PRR in uvr+ bacteria adapted to alkylating agents is accelerated by enzymes of adaptive response in the absence of antagonism between the SOS response and the adaptive response.

UI	MeSH Term	Description	Entries
D008741	Methyl Methanesulfonate	An alkylating agent in cancer therapy that may also act as a mutagen by interfering with and causing damage to DNA.	Methylmethane Sulfonate,Dimethylsulfonate,Mesilate, Methyl,Methyl Mesylate,Methyl Methylenesulfonate,Methylmesilate,Mesylate, Methyl,Methanesulfonate, Methyl,Methyl Mesilate
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D004249	DNA Damage	Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.	DNA Injury,DNA Lesion,DNA Lesions,Genotoxic Stress,Stress, Genotoxic,Injury, DNA,DNA Injuries
D004260	DNA Repair	The removal of DNA LESIONS and/or restoration of intact DNA strands without BASE PAIR MISMATCHES, intrastrand or interstrand crosslinks, or discontinuities in the DNA sugar-phosphate backbones.	DNA Damage Response
D004261	DNA Replication	The process by which a DNA molecule is duplicated.	Autonomous Replication,Replication, Autonomous,Autonomous Replications,DNA Replications,Replication, DNA,Replications, Autonomous,Replications, DNA
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
D005020	Ethyl Methanesulfonate	An antineoplastic agent with alkylating properties. It also acts as a mutagen by damaging DNA and is used experimentally for that effect.	Ethylmethane Sulfonate,Ethyl Mesilate,Ethyl Mesylate,Ethylmesilate,Ethylmesylate,Mesilate, Ethyl,Mesylate, Ethyl,Methanesulfonate, Ethyl,Sulfonate, Ethylmethane
D005838	Genotype	The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.	Genogroup,Genogroups,Genotypes
D000222	Adaptation, Physiological	The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.	Adaptation, Physiologic,Adaptations, Physiologic,Adaptations, Physiological,Adaptive Plasticity,Phenotypic Plasticity,Physiological Adaptation,Physiologic Adaptation,Physiologic Adaptations,Physiological Adaptations,Plasticity, Adaptive,Plasticity, Phenotypic