National Institute of Animal Health (NIAH)

Topics in Animal Health Research 2014

13. Mutagenesis in the major outer membrane protein gene of Histophilus somni by an allelic exchange method


Histophilus somni causes a variety of diseases in cattle and sheep. The sequence of major outer membrane protein (MOMP) gene, a potential virulence factor, of H. somni is significantly different between pathogenic and nonpathogenic strains. However, functional roles of the MOMP gene from H. somni have not yet been elucidated due to a lack of easily applicable mutagenesis methods. In this study, we used a PCR-amplified mutated DNA region flanked by an antibiotic for site-directed mutagenesis via homologous recombination in H. somni non-pathogenic strain and pathogenic strain. We observed no obvious changes in the whole cell protein, except the change in MOMP size, and no significant phenotypic difference in growth in broth medium between the wild-type strain and its isogenic MOMP mutant. This genetic approach is expected to improve our understanding of MOMP functions as a virulence factor of H. somni.
(Bacterial and Parasitic Disease Research Division)


Ueno Y. et al (2014) J. Microbiol. Methods. 106:83-92