First Evidence of a Potential Antimicrobial Activity of Bacterial Laccase Against Various Plant Pathogens

Abstract

The present study deals with antimicrobial activity analysis of Pseudomonas putida LUA15.1 and its extracellular laccase, against six fungal plant pathogens viz., Fusarium oxysporum, Phytophthora capsici, Pythium aphanidermatum, Alternaria zinniae, Dematophora necatrix and Sclerotium rolfsii, and three bacterial pathogens viz., Ralstonia solanacearum, Xanthomonas axonopodis and Agrobacterium tumefaciens. Bacterial culture of Pseudomonas putida LUA15.1 and both crude and purified laccase enzyme preparations inhibited the mycelial growth and morphology of all six fungal pathogens. Both crude and purified laccase enzyme preparations showed variable zones of inhibition against three bacterial pathogens viz., Ralstonia solanacearum, Xanthomonas axonopodis and Agrobacterium tumefaciens. To the best of our knowledge this is the first report of successful control of various fungal and bacterial plant pathogens by bacterial laccase.