Biomaterial Database

Degradation of N-nitrosamines by intestinal bacteria. 1975

I R Rowland, and P Grasso

A major proportion of bacterial types, common in the gastrointestinal tract of many animals and man, were active in degrading diphenylnitrosamine and dimethylnitrosamine, the former being degraded more rapidly than the latter. At low nitrosamine concentrations (is less than 0.05 micronmol/ml), approximately 55% of added diphenylnitrosamine, 30% of N-nitrosopyrrolidine, and 4% of dimethylnitrosamine were degraded. The route of nitrosamine metabolism by bacteria appears to be different from that proposed for breakdown by mammalian enzyme systems in that carbon dioxide and formate were not produced. In bacteria, the nitrosamines were converted to the parent amine and nitrite ion and, in addition, certain unidentified volatile metabolites were produced from dimethylnitrosamine by bacteria. The importance of bacteria in reducing the potential hazard to man of nitrosamines is discussed.

UI	MeSH Term	Description	Entries
D007709	Klebsiella	A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria whose organisms arrange singly, in pairs, or short chains. This genus is commonly found in the intestinal tract and is an opportunistic pathogen that can give rise to bacteremia, pneumonia, urinary tract and several other types of human infection.
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.
D009573	Nitrites	Salts of nitrous acid or compounds containing the group NO2-. The inorganic nitrites of the type MNO2 (where M	Nitrite
D009602	Nitrosamines	A class of compounds that contain a -NH2 and a -NO radical. Many members of this group have carcinogenic and mutagenic properties.	Nitrosamine
D009603	Nitroso Compounds	Organic compounds containing the nitroso (-N	Compounds, Nitroso
D011511	Proteus	A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that occurs in the intestines of humans and a wide variety of animals, as well as in manure, soil, and polluted waters. Its species are pathogenic, causing urinary tract infections and are also considered secondary invaders, causing septic lesions at other sites of the body.
D011550	Pseudomonas aeruginosa	A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.	Bacillus aeruginosus,Bacillus pyocyaneus,Bacterium aeruginosum,Bacterium pyocyaneum,Micrococcus pyocyaneus,Pseudomonas polycolor,Pseudomonas pyocyanea
D011759	Pyrrolidines	Compounds also known as tetrahydropyridines with general molecular formula (CH2)4NH.	Tetrahydropyridine,Tetrahydropyridines
D002250	Carbon Radioisotopes	Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.	Radioisotopes, Carbon
D003124	Colorimetry	Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)