Biosynthesis of cryptic lipopolysaccharide glycoforms in Haemophilus influenzae involves a mechanism similar to that required for O-antigen synthesis.
It is generally thought that mucosal bacterial pathogens of the genera Haemophilus, Neisseria, and Moraxella elaborate lipopolysaccharide (LPS) that is fundamentally different from that of enteric organisms that express O-specific polysaccharide side chains. Haemophilus influenzae elaborates short-chain LPS that has a role in the pathogenesis of H. influenzae infections. We show that the synthesis of LPS in this organism can no longer be as clearly distinguished from that in other gram-negative bacteria that express an O antigen. We provide evidence that a region of the H. influenzae genome, the hmg locus, is involved in the synthesis of glycoforms in which tetrasaccharide units are added en bloc, not stepwise, to the normal core glycoforms, similar to the biosynthesis of an O-antigen.
Molecular Infectious Diseases Group, University of Oxford Department of Paediatrics, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford OX3 9DS, United Kingdom. derek.hood@paediatrics.oxford.ac.uk
Derek W
DW
Hood
Gaynor
G
Randle
Andrew D
AD
Cox
Katherine
K
Makepeace
Jianjun
J
Li
Elke K H
EK
Schweda
James C
JC
Richards
E Richard
ER
Moxon
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002240:Carbohydrate Sequence; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006193:Haemophilus influenzae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D006801:Humans; D008070:Lipopolysaccharides / Q000096:biosynthesis* / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods; D051379:Mice; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D019081:O Antigens / Q000096:biosynthesis*
D001426:Bacterial Proteins; D008070:Lipopolysaccharides; D019081:O Antigens; D019158:N-Acetylneuraminic Acid