Mutagenesis with the transposon Tn916 was used as a strategy to identify genes required for synthesis of the Gal α(1-4) βGal component of Haemophilus influenzae strain RM7004 lipopolysaccharide. Insertion of Tn916 into an open reading frame (ORF) encoding a protein with 75% homology to the Escherichia coli methionine related protein (Mrp) is described. Mutations in mrp resulted in loss of reactivity with monoclonal antibody (mAb) 4C4, which recognises Gal α(1-4) βGal, and expression of LPS with a different electrophoretic profile to that of wild-type RM7004. An unexpected feature of this mutation was that it appeared to influence the number of copies of 5'-CAAT-3' present in lic2A, a gene which is also required for biosynthesis and phase variable expression of the Gal α(1-4) βGal LPS epitope.
biosynthesis, Haemophilus influenzae, LPS, lipopolysaccharide biosynthesis, mutagenesis
NCBI PubMed ID: 8978086Journal NLM ID: 8902526Publisher: Oxford University Press
Institutions: Molecular Infectious Diseases Group. Dept. of Paediatrics, University of Oxford, Institute of Molecular Medicine, John Radcliffe Hospital, Headinglon, Oxford OX3 7TE, UK
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