摘要:Trichosporon asahii is a pathogenic fungus that causes severe, deep-seated fungal infections in neutropenic patients
. Elucidating the infection mechanisms of
T. asahii based on genetic studies requires a specific gene-targeting system. Here, we established an efficient gene-targeting system in a highly pathogenic
T. asahii strain identified using the silkworm infection model. By comparing the pathogenicity of
T. asahii clinical isolates in a silkworm infection model,
T. asahii MPU129 was identified as a highly pathogenic strain. Using an
Agrobacterium tumefaciens-mediated gene transfer system, we obtained a
T. asahii MPU129 mutant lacking the
ku70 gene, which encodes the Ku70 protein involved in the non-homologous end-joining repair of DNA double-strand breaks. The
ku70 gene-deficient mutant showed higher gene-targeting efficiency than the wild-type strain for constructing a mutant lacking the
cnb1 gene, which encodes the beta-subunit of calcineurin. The
cnb1 gene-deficient mutant showed reduced pathogenicity against silkworms compared with the parental strain. These results suggest that an efficient gene-targeting system in a highly pathogenic
T. asahii strain is a useful tool for elucidating the molecular mechanisms of
T. asahii infection.