%0 Journal Article %A Hobb, Rhonda I. %A Tseng, Hsing-Ju %A Downes, John E. %A Terry, Tamsin D. %A Blackall, Patrick J. %A Takagi, Masami %A Jennings, Michael P. %T Molecular analysis of a haemagglutinin of Haemophilus paragallinarumaaThe GenBank accession numbers for the sequences determined in this work are AF491817–AF491827. %D 2002 %J Microbiology, %V 148 %N 7 %P 2171-2179 %@ 1465-2080 %R https://doi.org/10.1099/00221287-148-7-2171 %K HI, haemagglutination inhibition %K serotyping antigen %K AP, alkaline phosphatase %K HA, haemagglutination activity %K infectious coryza %K outer-membrane protein %I Microbiology Society, %X The gene encoding a haemagglutinin of H. paragallinarum, hagA, has been identified and the full-length nucleotide sequence determined. A ∼39 kDa protein, recognized by an anti-haemagglutinin monoclonal antibody, mAb4D, was purified from H. paragallinarum strain 0083 and the N-terminal sequence obtained. The full-length nucleotide sequence was obtained by inverse PCR and the deduced amino acid sequence of the protein encoded was shown to be similar to other outer-membrane proteins of closely related organisms in the HAP group (Haemophilus, Actinobacillus, Pasteurella), especially the P5 protein of Haemophilus influenzae. The hagA gene was cloned into a His-tag expression vector and overexpressed in Escherichia coli strain M15(pREP4). The identity of the purified recombinant protein as a H. paragallinarum haemagglutinin was confirmed by haemagglutination of chicken red blood cells and reactivity, in a Western blot, with the monoclonal antibody specific for the serovar A haemagglutinin. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-148-7-2171