Enhanced production of nargenicin A(1) and generation of novel glycosylated derivatives.

다국어 초록 (Multilingual Abstract)

<P>Nargenicin A(1), an antibacterial polyketide macrolide produced by Nocardia sp. CS682, was enhanced by increasing the pool of precursors using different sources. Furthermore, by using engineered strain Nocardia sp. ACC18 and supplementation of glucose and glycerol, enhancement was similar to 7.1 fold in comparison to Nocardia sp. CS682 without supplementation of any precursors. The overproduced compound was validated by mass spectrometry and nuclear magnetic resonance analyses. The novel glycosylated derivatives of purified nargenicin A(1) were generated by efficient one-pot reaction systems in which the syntheses of uridine diphosphate (UDP)-alpha-D-glucose and UDP-alpha-D-2-deoxyglucose were modified and combined with glycosyltransferase (GT) from Bacillus licheniformis. Nargenicin A(1) 11-O-beta- D-glucopyranoside, nargenicin A(1) 18-O-beta-D-glucopyranoside, nargenicin A(1)11 18-O-beta-D- diglucopyranoside, and nargenicin 11-O-beta-D-2-deoxyglucopyranoside were generated. Nargenicin A(1) 11-O-beta-D-glucopyranoside was structurally elucidated by ultra-high performance liquid chromatography-photodiode array (UPLC-PDA) conjugated with high-resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS), supported by one- and two-dimensional nuclear magnetic resonance studies, whereas other nargenicin A(1) glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The overall conversion studies indicated that the one-pot synthesis system is a highly efficient strategy for production of glycosylated derivatives of compounds like macrolides as well. Furthermore, assessment of solubility indicated that there was enhanced solubility in the case of glycoside, although a substantial increase in activity was not observed.</P>