Substrate Recognition Site 5 Of Cyp51 Protein Contributes To Azole Binding In Rice Blast Fungus Maganporthe Oryzae

Azole compounds used in agriculture to combat Maganporthe oryzae, the causal agent of rice blast disease, represent effective inhibitors of the sterol 14 alpha-demethylase (CYP51) which is related to the formation of ergosterol. Since most of them exhibit a similar mode of action, resistance has become even more severe. Detailed research on the structural characteristics of CYP51 may help to develop more effective drugs. In this study, the azole binding potency of key conserved residues of two substrate recognition sites of CYP51 protein from M. oryzae (MoCYP51B) was investigated via site directed mutagenesis followed by spectral analysis. According to results of binding spectra in the presence of diniconazole, the K-d values of MoCYP51B with mutations I367W and V374Y was significantly (P < 0.05) increased in comparison to wild-type controls, indicating that the residues 1367 and V374 of the MoCYP51B substrate recognition site 5 had critical contribution to azole binding. This study may provide useful insights into the studies and designs of novel antifungal agents for M. oryzae. (C) 2020 Friends Science Publishers