title: Engineered Corynebacterium glutamicum as an endotoxin-free platform strain for lactate-based polyester production.
abstract: The first biosynthetic system for lactate (LA)-based polyesters was previously created in recombinant Escherichia coli (Taguchi et al. 2008). Here, we have begun efforts to upgrade the prototype polymer production system to a practical stage by using metabolically engineered Gram-positive bacterium Corynebacterium glutamicum as an endotoxin-free platform. We designed metabolic pathways in C. glutamicum to generate monomer substrates, lactyl-CoA (LA-CoA), and 3-hydroxybutyryl-CoA (3HB-CoA), for the copolymerization catalyzed by the LA-polymerizing enzyme (LPE). LA-CoA was synthesized by D: -lactate dehydrogenase and propionyl-CoA transferase, while 3HB-CoA was supplied by β-ketothiolase (PhaA) and NADPH-dependent acetoacetyl-CoA reductase (PhaB). The functional expression of these enzymes led to a production of P(LA-co-3HB) with high LA fractions (96.8 mol%). The omission of PhaA and PhaB from this pathway led to a further increase in LA fraction up to 99.3 mol%. The newly engineered C. glutamicum potentially serves as a food-grade and biomedically applicable platform for the production of poly(lactic acid)-like polyester.
authors: Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, 060-8628, Japan.
authors: Yuyang
authors: Y
authors: Song
authors: Ken'ichiro
authors: K
authors: Matsumoto
authors: Miwa
authors: M
authors: Yamada
authors: Aoi
authors: A
authors: Gohda
authors: Christopher J
authors: CJ
authors: Brigham
authors: Anthony J
authors: AJ
authors: Sinskey
authors: Seiichi
authors: S
authors: Taguchi
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism*; D019344:Lactic Acid / Q000378:metabolism*; D053858:Metabolic Networks and Pathways / Q000235:genetics; D011091:Polyesters; D011108:Polymers / Q000378:metabolism*
chemical_list: D000214:Acyl Coenzyme A; D011091:Polyesters; D011108:Polymers; C047009:lactoyl-coenzyme A; C030372:3-hydroxybutyryl-coenzyme A; D019344:Lactic Acid; C033616:poly(lactide)