Large scale production of cyclohexanone monooxygenase from Escherichia coli TOP10 pQR239

The cyclohexanone monooxygenase (CHMO) from Acinetobacter calcoaceticus NCI MB 9871 has been cloned into Escherichia coli in an L-arabinose inducible v ector. The recombinant E. coli containing the L-arabinose inducible CHMO wa s grown at 1.5 litres under controlled conditions to determine the paramete rs for growth and induction. It was found that induction with 0.1% (w/v) L- arabinose at late logarithmic phase of growth and growth for a further 2.5 to 3 h gave the optimal CHMO titre (similar to 3500 U.1(-1).630 U . g dry c ell weight(-1)). High dissolved oxygen concentrations were shown to be dele terious to the CHMO titre. This influenced the strategy for growth and indu ction, and was optimal when the oxygen uptake rate was maximized but the di ssolved oxygen concentration was zero. Finally, a 300 litre scale fermentat ion was carried out giving a total CHMO titre of >8 x 10(5) U. (C) 2001 Els evier Science Inc. All rights reserved.