Enzymatic properties of the membrane-bound NADH oxidase system in the aerobic respiratory chain of Bacillus cereus.
Membranes prepared from Bacillus cereus KCTC 3674, grown aerobically on a complex medium, oxidized NADH exclusively, whereas deamino-NADH was little oxidized. The respiratory chain-linked NADH oxidase exhibited an apparent K(m) value of approximately 65 microM for NADH. The maximum activity of the NADH oxidase was obtained at about pH 8.5 in the presence of 0.1 M KCl (or NaCl). Respiratory chain inhibitor 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO) inhibited the activity of the NADH oxidase by about 90% at a concentration of 40 microM. Interestingly, rotenone and capsaicin inhibited the activity of the NADH oxidase by about 60% at a concentration of 40 microM and the activity was also highly sensitive to Ag(+).
Kim
Man Suk
MS
Department of Microbiology, Changwon National University, Sarim-dong, Changwon, Kyungnam 641-773, Korea.
Kim
Young Jae
YJ
D001409:Bacillus cereus / Q000166:cytology / Q000201:enzymology* / Q000378:metabolism; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D004579:Electron Transport / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009243:NAD / Q000737:chemistry / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D012492:Salts / Q000737:chemistry; D014475:Uncoupling Agents / Q000378:metabolism
D001426:Bacterial Proteins; D009097:Multienzyme Complexes; D012492:Salts; D014475:Uncoupling Agents; D009243:NAD; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases