Biomaterial Database

Induction of base substitution mutations by aflatoxin B1 is mucAB dependent in Escherichia coli. 1988

P L Foster, and J D Groopman, and E Eisenstadt

Division of Environmental Health, Boston University School of Public Health, Massachusetts 02118.

Recovery of aflatoxin B1-induced base substitution mutations in Escherichia coli was almost completely dependent on the presence of the SOS-mutagenesis-enhancing operon mucAB+; the normal E. coli analog, umuDC+, was not sufficient. Yet aflatoxin B1 induced the SOS response, including the umuDC operon, as well as did UV light. Neither preinduction of the SOS response nor the presence of additional copies of umuDC+ allowed the recovery of aflatoxin B1-induced base substitutions. Thus, the premutagenic DNA lesions induced by aflatoxin B1 reveal a functional difference between UmuDC and MucAB. We estimate that in the presence of MucAB the probability that aflatoxin B1-induced DNA lesions will be converted into mutations is increased at least 10-fold.

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
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
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
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial
D000348	Aflatoxins	Furano-furano-benzopyrans that are produced by ASPERGILLUS from STERIGMATOCYSTIN. They are structurally related to COUMARINS and easily oxidized to an epoxide form to become ALKYLATING AGENTS. Members of the group include AFLATOXIN B1; aflatoxin B2, aflatoxin G1, aflatoxin G2; AFLATOXIN M1; and aflatoxin M2.	Aflatoxin
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D013014	SOS Response, Genetics	An error-prone mechanism or set of functions for repairing damaged microbial DNA. SOS functions (a concept reputedly derived from the SOS of the international distress signal) are involved in DNA repair and mutagenesis, in cell division inhibition, in recovery of normal physiological conditions after DNA repair, and possibly in cell death when DNA damage is extensive.	SOS Response (Genetics),SOS Box,SOS Function,SOS Induction,SOS Region,SOS Repair,SOS Response,SOS System,Box, SOS,Function, SOS,Functions, SOS,Genetics SOS Response,Genetics SOS Responses,Induction, SOS,Inductions, SOS,Region, SOS,Regions, SOS,Repair, SOS,Repairs, SOS,Response, Genetics SOS,Response, SOS,Response, SOS (Genetics),Responses, Genetics SOS,Responses, SOS,Responses, SOS (Genetics),SOS Functions,SOS Inductions,SOS Regions,SOS Repairs,SOS Responses,SOS Responses (Genetics),SOS Responses, Genetics,SOS Systems,System, SOS,Systems, SOS
D016604	Aflatoxin B1	A potent hepatotoxic and hepatocarcinogenic mycotoxin produced by the Aspergillus flavus group of fungi. It is also mutagenic, teratogenic, and causes immunosuppression in animals. It is found as a contaminant in peanuts, cottonseed meal, corn, and other grains. The mycotoxin requires epoxidation to aflatoxin B1 2,3-oxide for activation. Microsomal monooxygenases biotransform the toxin to the less toxic metabolites aflatoxin M1 and Q1.	Aflatoxin B(1),Aflatoxin B,Aflatoxin B1 Dihydrochloride, (6aR-cis)-Isomer,Aflatoxin B1, (6aR-cis)-Isomer, 14C-Labeled,Aflatoxin B1, (6aR-cis)-Isomer, 2H-Labeled,Aflatoxin B1, (6aR-cis)-Isomer, 3H-Labeled,Aflatoxin B1, cis(+,-)-Isomer,HSDB-3453,NSC-529592,HSDB 3453,HSDB3453,NSC 529592,NSC529592