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Title: Engineering acetyl-CoA supply and ERG9 repression to enhance mevalonate production in Saccharomyces cerevisiae
Abstract

Mevalonate is a key precursor in isoprenoid biosynthesis and a promising commodity chemical. Although mevalonate is a native metabolite in Saccharomyces cerevisiae, its production is challenged by the relatively low flux toward acetyl-CoA in this yeast. In this study we explore different approaches to increase acetyl-CoA supply in S. cerevisiae to boost mevalonate production. Stable integration of a feedback-insensitive acetyl-CoA synthetase (Se-acsL641P) from Salmonella enterica and the mevalonate pathway from Enterococcus faecalis results in the production of 1,390 ± 10 mg/l of mevalonate from glucose. While bifid shunt enzymes failed to improve titers in high-producing strains, inhibition of squalene synthase (ERG9) results in a significant enhancement. Finally, increasing coenzyme A (CoA) biosynthesis by overexpression of pantothenate kinase (CAB1) and pantothenate supplementation further increased production to 3,830 ± 120 mg/l. Using strains that combine these strategies in lab-scale bioreactors results in the production of 13.3 ± 0.5 g/l, which is ∼360-fold higher than previously reported mevalonate titers in yeast. This study demonstrates the feasibility of engineering S. cerevisiae for high-level mevalonate production.

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Award ID(s):
1751840
NSF-PAR ID:
10360880
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Journal of Industrial Microbiology and Biotechnology
Volume:
48
Issue:
9-10
ISSN:
1367-5435
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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