title: KpsF is the arabinose-5-phosphate isomerase required for 3-deoxy-D-manno-octulosonic acid biosynthesis and for both lipooligosaccharide assembly and capsular polysaccharide expression in Neisseria meningitidis.
abstract: We have identified and defined the function of kpsF of Neisseria meningitidis and the homologues of kpsF in encapsulated K1 and K5 Escherichia coli. KpsF was shown to be the arabinose-5-phosphate isomerase, an enzyme not previously identified in prokaryotes, that mediates the interconversion of ribulose 5-phosphate and arabinose 5-phosphate. KpsF is required for 3-deoxy-d-manno-octulosonic acid (Kdo) biosynthesis in N. meningitidis. Mutation of kpsF or the gene encoding the CMP-Kdo synthetase (kpsU/kdsB) in N. meningitidis resulted in expression of a lipooligosaccharide (LOS) structure that contained only lipid A and reduced capsule expression in the five invasive disease-associated meningococcal serogroups (A, B, C, Y, and W-135). The step linking meningococcal capsule and LOS biosynthesis was shown to be Kdo production as the expression of capsule was wild type in a Kdo transferase (kdtA) mutant. Thus, in addition to lipooligosaccharide assembly, Kdo is required for meningococcal capsular polysaccharide expression. Furthermore, N. meningitidis, unlike enteric Gram-negative bacteria, can survive and synthesize only unglycosylated lipid A.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, the Department of Veterans Affairs Medical Center, Atlanta, Georgia 30033, USA.
authors.forename: Yih-Ling
authors.initials: YL
authors.lastname: Tzeng
authors.forename: Anup
authors.initials: A
authors.lastname: Datta
authors.forename: Christy
authors.initials: C
authors.lastname: Strole
authors.forename: V S Kumar
authors.initials: VS
authors.lastname: Kolli
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Birck
authors.forename: William P
authors.initials: WP
authors.lastname: Taylor
authors.forename: Russell W
authors.initials: RW
authors.lastname: Carlson
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Woodard
authors.forename: David S
authors.initials: DS
authors.lastname: Stephens
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins; D008070:Lipopolysaccharides / Q000096:biosynthesis* / Q000737:chemistry; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009345:Neisseria meningitidis / Q000201:enzymology / Q000235:genetics*; D010957:Plasmids; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000378:metabolism; D015183:Restriction Mapping; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013400:Sugar Acids / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C102536:KpsF protein, E coli; D008070:Lipopolysaccharides; D011135:Polysaccharides, Bacterial; D011994:Recombinant Proteins; D013400:Sugar Acids; C023023:lipid-linked oligosaccharides; C002532:2-keto-3-deoxyoctonate; D019747:Aldose-Ketose Isomerases; C041486:arabinose-5-phosphate isomerase