| 초록 |
PikC represents a cytochrome P450 (CYP) monooxygenase involved in the biosynthesis of pikromycin in Streptomyces venezualae. It is a unique enzyme and can oxidize a variety of macrolides. Conditions for the production of soluble PikC in Escherichia coli (E. coli) were optimized. The maximum productivity of PikC was reported to 29.2 µg ml-1 OD600-1 when the cultures were induced with 0.7 mM isopropyl-β-D-thiogalactopyranoside (IPTG) at 20℃ for 12 h. Under these conditions, the concentrations of soluble and insoluble PikC were determined to be 20.6 mg ml-1 and 5.1 mg ml-1, which corresponded to the 80.2% and 19.8% of the total PikC respectively. Within the designed range of variables, overall productivities of soluble PikC were 1.9 fold for the cultures induced with IPTG at 20℃ than for those at 37℃. A gradual decrease of the production of soluble PikC was found for 0.4 mM and 0.7 mM IPTG inductions with the increasing OD600 at the time of induction, but the production decreased drastically for 1.0 mM IPTG induction when cultures exceeded OD600 from 0.41. |
