Bacillus sp. strain M10 as a potential biocontrol agent protecting chili pepper and tomato fruits from anthracnose disease caused by Colletotrichum capsici

Bacillus sp. strain M10 was observed to produce an antifungal protein that inhibits the growth of Colletotrichum capsici, which is the causal agent of anthracnose disease of chili pepper and tomato. Ammonium sulfate precipitation, anion exchange chromatography, and sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the protein was approximately 55.4 kDa. The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis and a subsequent sequence database search indicated the antifungal protein was most similar to the Bacillus amyloliquefaciens vegetative catalase (KatA) protein. Light microscopy observation revealed that the antifungal protein induced abnormal hyphal elongation and conidial swelling and rupture. The protein considerably inhibited anthracnose development and protected the fruits from C. capsici infection. Thus, Bacillus sp. strain M10 and/or its putative catalase may be useful as a post-harvest biocontrol agent that protects chili pepper and tomato fruits from anthracnose disease caused by C. capsici.