title: Modulation of guanosine nucleotides biosynthetic pathways enhanced GDP-L-fucose production in recombinant Escherichia coli.
abstract: Guanosine 5'-triphosphate (GTP) is the key substrate for biosynthesis of guanosine 5'-diphosphate (GDP)-L-fucose. In this study, improvement of GDP-L-fucose production was attempted by manipulating the biosynthetic pathway for guanosine nucleotides in recombinant Escherichia coli-producing GDP-L-fucose. The effects of overexpression of inosine 5'-monophosphate (IMP) dehydrogenase, guanosine 5'-monophosphate (GMP) synthetase (GuaB and GuaA), GMP reductase (GuaC) and guanosine-inosine kinase (Gsk) on GDP-L-fucose production were investigated in a series of fed-batch fermentations. Among the enzymes tested, overexpression of Gsk led to a significant improvement of GDP-L-fucose production. Maximum GDP-L-fucose concentration of 305.5 ± 5.3 mg l(-1) was obtained in the pH-stat fed-batch fermentation of recombinant E. coli-overexpressing Gsk, which corresponds to a 58% enhancement in the GDP-L-fucose production compared with the control strain overexpressing GDP-L-fucose biosynthetic enzymes. Such an enhancement of GDP-L-fucose production could be due to the increase in the intracellular level of GMP.
authors.affiliation: Department of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, Seoul, South Korea.
authors.forename: Won-Heong
authors.initials: WH
authors.lastname: Lee
authors.forename: So-Yeon
authors.initials: SY
authors.lastname: Shin
authors.forename: Myoung-Dong
authors.initials: MD
authors.lastname: Kim
authors.forename: Nam Soo
authors.initials: NS
authors.lastname: Han
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Seo
mesh_terms: D053898:Biosynthetic Pathways; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D005818:Genetic Engineering; D006153:Guanosine Diphosphate / Q000096:biosynthesis*; D006154:Guanosine Diphosphate Fucose / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D006153:Guanosine Diphosphate; D006154:Guanosine Diphosphate Fucose