Efflux transporter engineering markedly improves amorphadiene production in Escherichia coli. Issue 8 (4th February 2016)

• Record Type: Journal Article
• Authors: Zhang, Congqiang; Chen, Xixian; Stephanopoulos, Gregory; Too, Heng‐Phon
• Is Part Of: Biotechnology and bioengineering. Volume 113:Issue 8(2016)
• Page Start: 1755
• Page End: 1763
• Publication Date: 2016-02-04
• Subjects: efflux pump -- transporter engineering -- amorphadiene -- TolC -- lipopolysaccharide transport system -- artemisinin; Biotechnology -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/bit.25943
• Languages: English
• ISSNs: 0006-3592

Abstract

ABSTRACT: Metabolic engineering aims at altering cellular metabolism to produce valuable products at high yields and titers. Achieving high titers and productivity can be challenging if final products are largely accumulated intracellularly. A potential solution to this problem is to facilitate the export of these substances from cells by membrane transporters. Amorphadiene, the precursor of antimalarial drug artemisinin, is known to be secreted from Escherichia coli overexpressing the biosynthetic pathway. In order to assess the involvement of various endogenous efflux pumps in amorphadiene transport, the effects of single gene deletion of 16 known multidrug‐resistant membrane efflux transporters were examined. The outer membrane protein TolC was found to be intimately involved in amorphadiene efflux. The overexpression of tolC together with ABC family transporters ( macAB ) or MFS family transporters ( emrAB or emrKY ) enhanced amorphadiene titer by more than threefold. In addition, the overexpression of transporters in the lipopolysaccharide transport system ( msbA, lptD, lptCABFG ) was found to improve amorphadiene production. As efflux transporters often have a wide range of substrate specificity, the multiple families of transporters were co‐expressed and synergistic benefits were observed in amorphadiene production. This strategy of screening and then rationally engineering transporters can be used to improve the production of other valuable compounds in E. coli . Biotechnol. Bioeng. 2016;113: 1755–1763. © 2016 Wiley Periodicals, Inc. Abstract : A strategy of screening and then rationally engineering transporters was developed in the study, which could be applied for improving the production of many valuable compounds in Escherichia coli . Using this strategy, amorphadiene production was greatly improved by overexpression of TolC with its related transporter system.