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

• Published in: The Journal of biological chemistry Vol. 277; no. 27; pp. 24103 - 24113
• Main Authors: Tzeng, Yih-Ling, Datta, Anup, Strole, Christy, Kolli, V. S. Kumar, Birck, Matthew R., Taylor, William P., Carlson, Russell W., Woodard, Ronald W., Stephens, David S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05-07-2002; American Society for Biochemistry and Molecular Biology
• Subjects: Aldose-Ketose Isomerases - chemistry; Aldose-Ketose Isomerases - genetics; Aldose-Ketose Isomerases - metabolism; Amino Acid Sequence; Amino Acid Substitution; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Escherichia coli - metabolism; Escherichia coli Proteins; Lipopolysaccharides - biosynthesis; Lipopolysaccharides - chemistry; Molecular Sequence Data; Mutagenesis, Site-Directed; Neisseria meningitidis - enzymology; Neisseria meningitidis - genetics; Plasmids; Polysaccharides, Bacterial - biosynthesis; Recombinant Proteins - metabolism; Restriction Mapping; Sequence Alignment; Sequence Homology, Amino Acid; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Sugar Acids - metabolism
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M200931200

We have identified and defined the function ofkpsF of Neisseria meningitidis and the homologues of kpsF in encapsulated K1 and K5Escherichia 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 inN. meningitidis. Mutation of kpsF or the gene encoding the CMP-Kdo synthetase (kpsU/kdsB) inN. 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.