| Abstrakt: |
Arima, Kei(University of Tokyo, Tokyo, Japan), and Tetuo Oka. Cyanide resistance in Achromobacter. I. Induced formation of cytochrome a2and its role in cyanide-resistant respiration. J. Bacteriol. 90:734–743. 1965.—By following the cytochrome concentrations during the growth cycle and under various conditions (aerobic, aerobic plus KCN, reduced aeration, anaerobic plus NaNO3) in Achromobacterstrain D, a close relationship between the formation of cytochrome a2(and a1) and the difficulty of oxygen utilization was demonstrated. Cytochrome o, which was the only oxidase found in aerobic log-phase cells, was present in bacterial cells grown under various conditions; the amount present had no relation to the degree of cyanide resistance. On the other hand, cytochrome a2(and a1) was inducible, and a close relation was observed between the amount of cytochrome and resistance to cyanide. Spectrophotometric observations indicated that, among the cytochromes present in resistant cells, cytochrome a2could be oxidized most easily in the presence of cyanide and that cytochrome b1could be oxidized without the oxidation of cytochrome a1. We concluded that cytochrome a2is a cyanide-resistant oxidase capable of catalyzing the oxidation of cytochromes in the presence of cyanide. Cytochrome a2is also resistant to azide, an inhibitor of cytochrome oxidase. |
