Biomaterial Database

Mutagenesis within the gastrointestinal tract determined by histidine auxotrophs of Salmonella typhimurium. 1980

P Goldman, and J H Carter, and L A Wheeler

The Ames Salmonella mutants can be maintained for months within the gastrointestinal tract of otherwise germfree rats. The ingestion of various carcinogens, but not structurally related non-carcinogens, results in an increased concentration of his+ revertants in the feces. Rats, associated with strain TA1538, were also associated with either L. plantarum of B. vulgatus and with both of these strains. After 2-nitrofluorene ingestion (3.4 mg) the concentration of fecal revertants increased except in rats associated only with strains TA1538 and B. vulgatus. The concentration of B. vulgatus. The concentration of B. vulgatus in the stomach of individual rats correlated negatively with their response to 2-nitrofluorene. Since only B. vulgatus reduces nitrofluorene to the less mutagenic 2-aminofluorene, it appears that B. vulgatus diminishes the revertant response by metabolic removal of the more potent direct acting mutagen from the gut. The ingestion of 1,2-dimethylhydrazine (21 mg/kg) and azoxymethane (19 mg/kg) provokes increased fecal revertants only in some animals associated with strain TA1535 or TA100.

UI	MeSH Term	Description	Entries
D007778	Lactobacillus	A genus of gram-positive, microaerophilic, rod-shaped bacteria occurring widely in nature. Its species are also part of the many normal flora of the mouth, intestinal tract, and vagina of many mammals, including humans. Lactobacillus species are homofermentative and ferment a broad spectrum of carbohydrates often host-adapted but do not ferment PENTOSES. Most members were previously assigned to the Lactobacillus delbrueckii group. Pathogenicity from this genus is rare.
D008297	Male		Males
D009153	Mutagens	Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.	Clastogen,Clastogens,Genotoxin,Genotoxins,Mutagen
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
D002273	Carcinogens	Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.	Carcinogen,Oncogen,Oncogens,Tumor Initiator,Tumor Initiators,Tumor Promoter,Tumor Promoters,Initiator, Tumor,Initiators, Tumor,Promoter, Tumor,Promoters, Tumor
D004064	Digestive System	A group of organs stretching from the MOUTH to the ANUS, serving to breakdown foods, assimilate nutrients, and eliminate waste. In humans, the digestive system includes the GASTROINTESTINAL TRACT and the accessory glands (LIVER; BILIARY TRACT; PANCREAS).	Ailmentary System,Alimentary System
D004353	Drug Evaluation, Preclinical	Preclinical testing of drugs in experimental animals or in vitro for their biological and toxic effects and potential clinical applications.	Drug Screening,Evaluation Studies, Drug, Pre-Clinical,Drug Evaluation Studies, Preclinical,Drug Evaluations, Preclinical,Evaluation Studies, Drug, Preclinical,Evaluation, Preclinical Drug,Evaluations, Preclinical Drug,Medicinal Plants Testing, Preclinical,Preclinical Drug Evaluation,Preclinical Drug Evaluations,Drug Screenings,Screening, Drug,Screenings, Drug
D005243	Feces	Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.
D005856	Germ-Free Life	Animals not contaminated by or associated with any foreign organisms.	Axenic Animals,Gnotobiotics,Germfree Life,Animal, Axenic,Animals, Axenic,Axenic Animal,Germ Free Life,Gnotobiotic,Life, Germ-Free,Life, Germfree
D006639	Histidine	An essential amino acid that is required for the production of HISTAMINE.	Histidine, L-isomer,L-Histidine,Histidine, L isomer,L-isomer Histidine