Novel Monomeric Fungal Subtilisin Inhibitor from a Plant-Pathogenic Fungus, Choanephora cucurbitarum: Isolation and Molecular Characterization.

ABSTRACT: The bacterial protease inhibitor domains known as Streptomyces subtilisin inhibitors (SSI) are rarely found in fungi. Genome analysis of a fungal pathogen, Choanephora cucurbitarum KUS-F28377, revealed 11 SSI-like domains that are horizontally transferred and sequentially diverged during evolution. We investigated the molecular function of fungal SSI-like domains of C. cucurbitarum, designated "choanepins." Among the proteins tested, only choanepin9 showed inhibitory activity against subtilisin as the target protease, accounting for 47% of the inhibitory activity of bacterial SSI. However, the binding affinity (expressed as the dissociation constant [K_d ]) of choanepin9 measured via microscale thermophoresis was 21 nM, whereas that for bacterial SSI i

SUBMITTER: Pathiraja D 

PROVIDER: S-EPMC7642069 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature