Figure 2.

Identification of virulence factors of pathogens using a silkworm infection model. (a) Method for evaluating avirulent mutants from a gene‐deficient mutant library. The wild type strain of a pathogen or gene‐deficient mutants are injected into silkworms and the number that survive measured. (b) Strategies for clarifying the infectious systems of pathogenic microorganisms. A gene‐deficient mutant library of a pathogenic microorganism is prepared and new genes necessary for pathogenicity to silkworms identified. Furthermore, the pathogenicity of the identified mutants against mice is confirmed. Genetic analyses of the identified pathogenic genes and biochemical analysis of the proteins (gene products) are carried out.