Die reduktion von perchlorat durch bakterien—II: Die identität der nitratreduktase und des perchlorat reduzierenden enzyms aus B. Cereus
1965; Elsevier BV; Volume: 14; Issue: 9 Linguagem: Inglês
ISSN
1873-2968
Autores Tópico(s)Chemical Reactions and Isotopes
ResumoThe reduction of nitrate and chlorine-36 labelled perchlorate by cellfree extracts obtained from nitrate-adapted cells of Bacillus cereus is described. The reduction of both anions is ascribed to the same enzyme because both activities are equally dependent onthe hydrogen ion concentration, the incubation temperature and several electron donors and cofactors. There exists parallel inhibition of both activities by cyanide, azide and 2,4-dinitrophenol. The reduction of nitrate is inhibited by perchlorate in a competitive manner and vice versa. The product of perchlorate reduction is chlorate. Chlorate itself is reduced by the same cellfree preparation. Inhibition by chlorate of perchlorate reduction seems to be competitive with respect to perchlorate, though deviations from linearity in the Lineweaver-Burk pilots occur. The possible significance of this effect is discussed. Nitrite at high concentration is inhibitory to both nitrate and perchlorate reduction in a non-competitive manner.
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