loading page

Improvement of an Escherichia coli whole-cell biocatalyst for geranyl glucoside production using directed evolution
  • Julian Ruediger,
  • Wilfried Schwab
Julian Ruediger
Technical University of Munich
Author Profile
Wilfried Schwab
Technical University of Munich
Author Profile

Abstract

The biotechnological production of glycosides is an economically competitive manufacturing alternative to classical chemical synthesis. Through continuous production improvement, glycosides can now be used in low-cost products by various industries. However, many production systems still suffer from low yields. Directed evolution, coupled with a suitable screening method, can tackle this challenge. We generated glycosyltransferase mutants through error-prone-PCR and screened the library using a small-scale whole-cell biotransformation system. The screening of only 176 colonies yielded three putative candidates. Detailed investigations revealed that the reason for the increase in product titer was mainly due to different expression effects of the mutagenized genes rather than improved enzyme kinetics. In total, a 60-fold increase in product formation was achieved. Therefore, in addition to the quality of the mutant library, an efficient and stable expression system is crucial to achieve high concentrations of active enzyme and product, as formation of inclusion bodies and other inactive forms of the biocatalyst reduces productivity.

Peer review status:UNDER REVIEW

10 Mar 2021Submitted to Engineering Reports
10 Mar 2021Submission Checks Completed
10 Mar 2021Assigned to Editor
10 Mar 2021Editorial Decision: Revise Major
30 Apr 20211st Revision Received
04 May 2021Assigned to Editor
04 May 2021Submission Checks Completed
08 May 2021Reviewer(s) Assigned
21 May 2021Editorial Decision: Revise Major
28 May 20212nd Revision Received
31 May 2021Assigned to Editor
31 May 2021Submission Checks Completed
31 May 2021Reviewer(s) Assigned