Improved production of cytotoxic thailanstatins A and D through metabolic engineering of Burkholderia thailandensis MSMB43 and pilot scale fermentation

Date

2016-04-01

Authors

Liu, Xiangyang
Zhu, Hui
Biswas, Sreya
Cheng, Yi-Qiang

ORCID

0000-0001-9336-2593 (Cheng, Eric Yi-Qiang)

Journal Title

Journal ISSN

Volume Title

Publisher

Elsevier B.V.

Abstract

Thailanstatin A (TST-A) is a potent antiproliferative natural product discovered by our group from Burkholderia thailandensis MSMB43 through a genome-guided approach. The limited supply of TST-A, due to its low titer in bacterial fermentation, modest stability and very low recovery rate during purification, has hindered the investigations of TST-A as an anticancer drug candidate. Here we report the significant yield improvement of TST-A and its direct precursor, thailanstatin D (TST-D), through metabolic engineering of the thailanstatin biosynthetic pathway in MSMB43. Deletion of tstP, which encodes a dioxygenase involved in converting TST-A to downstream products including FR901464 (FR), resulted in 58% increase of the TST-A titer to 144.7 +/- 2.3 mg/L and 132% increase of the TST-D titer to 14.6 +/- 0.5 mg/L in the fermentation broth, respectively. Deletion of tstR, which encodes a cytochrome P450 involved in converting TST-D to TST-A, resulted in more than 7-fold increase of the TST-D titer to 53.2 +/- 12.1 mg/L in the fermentation broth. An execution of 90 L pilot-scale fed-batch fermentation of the tstP deletion mutant in a 120-L fermentor led to the preparation of 714 mg of TST-A with greater than 98.5% purity. The half-life of TST-D in a phosphate buffer was found to be at least 202 h, significantly longer than that of TST-A or FR, suggesting superior stability. However, the IC50 values of TST-D against representative human cancer cell lines were determined to be greater than those of TST-A, indicating weaker antiproliferative activity. This work enabled us to prepare sufficient quantities of TST-A and TST-D for our ongoing translational research.

Description

Citation

Liu, X., Zhu, H., Biswas, S., & Cheng, Y. Q. (2016). Improved production of cytotoxic thailanstatins A and D through metabolic engineering of Burkholderia thailandensis MSMB43 and pilot scale fermentation. Synthetic and systems biotechnology, 1(1), 34-38. https://doi.org/10.1016/j.synbio.2016.02.002

Rights

© 2016 Authors.

License

Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)