Enhancement of the antifungal activity ofBacillus subtilisF29-3 by the chitinase encoded byBacillus circulans chiAgene

Abstract

Bacillus subtilis F29–3 is an antagonistic bacterium against a wide range of fungal species. In order to determine the effect of chitinase on the antifungal activity of B. subtilis F29–3, a 2.4-kb DNA fragment containing the chiA gene of Bacillus circulans WL-12 was ligated into a shuttle vector pHY300PLK and transformed into B. subtilis F29–3. A bioassay conducted on the culture supernatant showed that, in comparison to the B. subtilis control strain, B. subtilis F29–3 expressing the chiA gene exhibited a greater inhibition of spore germination of Botrytis elliptica, indicating that chitinase could enhance the antifungal function conferred by B. subtilis F29–3.Key words: Bacillus subtilis, antifungal activity, chiA, Bacillus circulans.