Identification and characterization of Schizophyllum commune type I metacaspases.

ABSTRACT: The role of programmed cell death in filamentous fungi is not well-understood, but is important due to the role of fungi in opportunistic infections. Plants, fungi and protozoa do not have caspase genes, but instead express the homologous proteins denoted metacaspases. To better understand the role of metacaspases in fungi we present an analysis of the sequences and activities of all five Type I metacaspases from Schizophyllum commune (ScMC), a mushroom-forming basiodmycete that undergoes sexual reproduction. The five Type I metacaspases of S. commune can be divided into two groups based on sequence similarity. Enzymes both with and without the N-terminal prodomain are active, but here we report on the constructs without the prodomains (?pro). All five ScMC?pro proteins show the highest enzymatic activity between pH 7 and 8 and require calcium for optimal activity. Optimal Ca2+ concentrations for ScMC1?pro and ScMC2?pro are 50?mM, while ScMC3, ScMC4?pro and ScMC5?pro activity is optimal around 5?mM calcium. All five S. commune metacaspases have similar substrate specificity. They are most active with Arg in the P1 position and inactive with Asp in the P1 position.

SUBMITTER: Leang L 

PROVIDER: S-EPMC6895675 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature