ATTENUATION OF BACTERIA: MATERIALS AND METHODS RELATING THERETO

摘要

Attenuated microorganisms are prepared by mutating one or more genes selected from sopA, sopD, sipA, or a gene from within the pathogenicity island SPI-5, when the microorganism is Salmonella, or one or more homologous genes which correspond to said Salmonella genes, when the microorganism is another enteric bacteria. In comparison with the wild-type strains, the attenuated microorganisms have a reduced enteropathogenicity but substantially the same invasiveness. The attenuated microorganisms can be administered as vaccines against infection by enteric bacteria. Polypeptides encoded by sopA, pipD, orfX, pipC, pipB and pipA genes, variants thereof, and nucleic acids encoding those polypeptides, are also provided.