title: Large-scale production of UDP-galactose and globotriose by coupling metabolically engineered bacteria.
abstract: A large-scale production system of uridine 5'-diphospho-galactose (UDP-Gal) has been established by the combination of recombinant Escherichia coli and Corynebacterium ammoniagenes. Recombinant E. coli that overexpress the UDP-Gal biosynthetic genes galT, galK, and galU were generated. C. ammoniagenes contribute the production of uridine triphosphate (UTP), a substrate for UDP-Gal biosynthesis, from orotic acid, an inexpensive precursor of UTP. UDP-Gal accumulated to 72 mM (44 g/L) after a 21 h reaction starting with orotic acid and galactose. When E. coli cells that expressed the alpha1,4-galactosyltransferase gene of Neisseria gonorrhoeae were coupled with this UDP-Gal production system, 372 mM (188 g/L) globotriose (Galalpha1-4Galbeta1-4Glc), a trisaccharide portion of verotoxin receptor, was produced after a 36 h reaction starting with orotic acid, galactose, and lactose. No oligosaccharide by-products were observed in the reaction mixture. The production of globotriose was several times higher than that of UDP-Gal. The strategy of producing sugar nucleotides by combining metabolically engineered recombinant E. coli with a nucleoside 5'-triphosphate producing microorganism, and the concept of producing oligosaccharides by coupling sugar nucleotide production systems with glycosyltransferases, can be applied to the manufacture of other sugar nucleotides and oligosaccharides.
authors.affiliation: Tokyo Research Laboratories, Kyowa Hakko Kogyo Co., Ltd., Machida, Japan. skoizumi@kyowa.co.jp
authors.forename: S
authors.initials: S
authors.lastname: Koizumi
authors.forename: T
authors.initials: T
authors.lastname: Endo
authors.forename: K
authors.initials: K
authors.lastname: Tabata
authors.forename: A
authors.initials: A
authors.lastname: Ozaki
mesh_terms: D001483:Base Sequence; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003001:Cloning, Molecular; D003352:Corynebacterium / Q000235:genetics; D017931:DNA Primers; D004926:Escherichia coli / Q000235:genetics*; D008969:Molecular Sequence Data; D009344:Neisseria gonorrhoeae / Q000235:genetics; D010957:Plasmids; D011995:Recombination, Genetic; D014312:Trisaccharides / Q000096:biosynthesis* / Q000737:chemistry; D014531:Uridine Diphosphate Galactose / Q000096:biosynthesis*
chemical_list: D017931:DNA Primers; D014312:Trisaccharides; D014531:Uridine Diphosphate Galactose; C113460:globotriose