title: Antimutagenicity of cell fractions of microorganisms on potent mutagenic pyrolysates.
abstract: The inactivation of 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 2-amino-6-methyldipyrido[1,2-a: 3',2'-d]imidazole (Glu-P-1) by binding of mutagenic pyrolysate to fractions of microorganisms (their desmutagenic and bio-antimutagenic activity) was investigated. All strains bound Trp-P-1 effectively, but Glu-P-1 to a lesser extent. The Gram-negative bacteria (GNB) could bind about 10-20 micrograms/mg of Trp-P-1 more than the Gram-positive bacteria (GPB), and about 50-60 micrograms/mg more than the yeasts. The cell wall skeletons of all strains tested had great binding ability, but in the cytoplasm of all strains tested it was lower. The peptidoglycan, outer membrane, and glucan isolate from the cell wall skeletons showed the highest binding ability to Trp-P-1. The cell wall skeletons of the tested strains greatly inhibited the mutagenicity induced by Trp-P-1, and to a lower extent that of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx). Although the cultured broth and solution of cells extracted by phosphate buffer (pH 7.0) showed antimutagenicity against Trp-P-1, this activity was lower than the binding of Trp-P-1 to the cells. The cultured broth and freeze-dried cytoplasms of yeast cells showed bio-antimutagenicity towards Trp-P-1, but those of all bacteria tested did not.
authors.affiliation: Laboratory for Microbial Biochemistry, Faculty of Applied Biological Science, Hiroshima University, Japan.
authors.forename: X B
authors.initials: XB
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Ohta
mesh_terms: D000588:Amines / Q000037:antagonists & inhibitors / Q000633:toxicity; D016587:Antimutagenic Agents / Q000378:metabolism*; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001665:Binding Sites; D002243:Carbolines / Q000037:antagonists & inhibitors*; D002458:Cell Fractionation; D017358:Cell Wall Skeleton / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003593:Cytoplasm / Q000378:metabolism; D005936:Glucans / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D006571:Heterocyclic Compounds / Q000037:antagonists & inhibitors / Q000633:toxicity; D006358:Hot Temperature; D007093:Imidazoles / Q000037:antagonists & inhibitors*; D008351:Mannans / Q000378:metabolism; D009152:Mutagenicity Tests; D009153:Mutagens / Q000378:metabolism*; D010457:Peptidoglycan / Q000378:metabolism; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D015003:Yeasts / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
chemical_list: D000588:Amines; D016587:Antimutagenic Agents; D001425:Bacterial Outer Membrane Proteins; D002243:Carbolines; D017358:Cell Wall Skeleton; D005936:Glucans; D006571:Heterocyclic Compounds; D007093:Imidazoles; D008351:Mannans; D009153:Mutagens; D010457:Peptidoglycan; C023785:2-amino-6-methyldipyrido(1,2-a-3',2'-d)imidazole; C019132:3-amino-1,4-dimethyl-5H-pyrido(4,3-b)indole