title: Functional expression of Pseudomonas aeruginosa GDP-4-keto-6-deoxy-D-mannose reductase which synthesizes GDP-rhamnose.
abstract: Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that causes severe infections in a number of hosts from plants to mammals. A-band lipopolysaccharide of P. aeruginosa contains d-rhamnosylated O-antigen. The synthesis of GDP-D-rhamnose, the d-rhamnose donor in d-rhamnosylation, starts from GDP-D-mannose. It is first converted by the GDP-mannose-4,6-dehydratase (GMD) into GDP-4-keto-6-deoxy-D-mannose, and then reduced to GDP-D-rhamnose by GDP-4-keto-6-deoxy-D-mannose reductase (RMD). Here, we describe the enzymatic characterization of P. aeruginosa RMD expressed in Saccharomyces cerevisiae. Previous success in functional expression of bacterial gmd genes in S. cerevisiae allowed us to convert GDP-D-mannose into GDP-4-keto-6-deoxy-D-mannose. Thus, coexpression of the Helicobacter pylori gmd and P. aeruginosa rmd genes resulted in conversion of the 4-keto-6-deoxy intermediate into GDP-deoxyhexose. This synthesized GDP-deoxyhexose was confirmed to be GDP-rhamnose by HPLC, matrix-assisted laser desorption/ionization time-of-flight MS, and finally NMR spectroscopy. The functional expression of P. aeruginosa RMD in S. cerevisiae will provide a tool for generating GDP-rhamnose for in vitro rhamnosylation of glycoprotein and glycopeptides.
authors.affiliation: Department of Bacteriology and Immunology, Haartman Institute and Biomedicum, University of Helsinki, Finland.
authors.forename: Minna
authors.initials: M
authors.lastname: Mäki
authors.forename: Nina
authors.initials: N
authors.lastname: Järvinen
authors.forename: Jarkko
authors.initials: J
authors.lastname: Räbinä
authors.forename: Christophe
authors.initials: C
authors.lastname: Roos
authors.forename: Hannu
authors.initials: H
authors.lastname: Maaheimo
authors.forename: Risto
authors.initials: R
authors.lastname: Renkonen
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D017931:DNA Primers; D006156:Guanosine Diphosphate Sugars / Q000096:biosynthesis* / Q000378:metabolism; D007658:Ketone Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D017931:DNA Primers; C422949:GDP-rhamnose; D006156:Guanosine Diphosphate Sugars; D011994:Recombinant Proteins; D007658:Ketone Oxidoreductases; C449658:GDP-4-keto-6-deoxy-D-mannose reductase