The PacC transcription factor regulates secondary metabolite production and stress response, but has only minor effects on virulence in the insect pathogenic fungus Beauveria bassiana

Autor(es)

Luo, Zhibing ; Ren, Hui ; Mousa, Jarrod J. ; Rangel, Drauzio E. N. ; Zhang, Yongjun ; Bruner, Steven D. ; Keyhani, Nemat O.

• Tipo de documento: Artigo Científico
• Fonte: ENVIRONMENTAL MICROBIOLOGY; v. 19, n. 2, p. 788-802, FEB 2017.
• Citações Web of Science: 12

Resumo

The PacC transcription factor is an important component of the fungal ambient pH-responsive regulatory system. Loss of pacC in the insect pathogenic fungus Beauveria bassiana resulted in an alkaline pH-dependent decrease in growth and pH-dependent increased susceptibility to osmotic (salt, sorbitol) stress and SDS. Extreme susceptibility to Congo Red was noted irrespective of pH, and BbpacC conidia showed subtle increases in UV susceptibility. The BbPacC mutant showed a reduced ability to acidify media during growth due to failure to produce oxalic acid. The BbPacC mutant also did not produce the insecticidal compound dipicolinic acid, however, production of a yellow-colored compound was noted. The compound, named bassianolone B, was purified and its structure determined. Despite defects in growth, stress resistance, and oxalate/insecticidal compound production, only a small decrease in virulence was seen for the BbpacC strain in topical insect bioassays using larvae from the greater waxmoth, Galleria mellonella or adults of the beetle, Tenebrio molitor. However, slightly more pronounced decreases were seen in virulence via intrahemcoel injection assays (G. mellonella) and in assays using T. molitor larvae. These data suggest important roles for BbpacC in mediating growth at alkaline pH, regulating secondary metabolite production, and in targeting specific insect stages. (AU)

• Processo FAPESP: 10/06374-1 - Luz visível durante o crescimento induz aumento de tolerância de conídios a diferentes condições de estresse em fungos
• Beneficiário: Drauzio Eduardo Naretto Rangel
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 13/50518-6 - Genes relacionados com estresse são induzidos pela luz visível durante o crescimento micelial, resultando em aumento da tolerância de conídios a condições de estresse
• Beneficiário: Drauzio Eduardo Naretto Rangel
• Modalidade de apoio: Auxílio à Pesquisa - Regular