B. Soballe et Rk. Poole, AEROBIC AND ANAEROBIC REGULATION OF THE UBICA OPERON, ENCODING ENZYMES FOR THE FIRST 2 COMMITTED STEPS OF UBIQUINONE BIOSYNTHESIS IN ESCHERICHIA-COLI, FEBS letters, 414(2), 1997, pp. 373-376
The ubiCA operon of Escherichia coli encodes enzymes for the first two
steps of ubiquinone biosynthesis, A monolysogen (ubiC-lacZ operon fus
ion) was constructed to study ubiCA regulation, Expression was higher
during aerobic growth than anaerobically, and increased with rate of o
xygen supply, Although ubiquinone is implicated in antioxidant roles,
ubiC expression was not elevated in response to hydrogen peroxide or t
he redox cycling agent, paraquat, Glucose repressed expression and mut
ation of cya (encoding adenylate cyclase) increased expression, Anaero
bically utilised electron accepters (nitrite, nitrate, fumarate) did n
ot affect expression, ubiC expression appears to be negatively regulat
ed by Fm and IHF. (C) 1997 Federation of European Biochemical Societie
s.