Isolation and characterization of a novel Burkholderia cepacia with strong antifungal activity against Rhizoctonia solani

Abstract

Strain CF-66 with strong antifungal activity against Rhizoctonia solani was isolated from compost samples. It is clearly demonstrated that strain CF-66 is belonging to Burkholderia cepacia complex by the morphological and biochemical tests and 16S rDNA sequence. The B. cepacia complex consists of a group of bacteria currently organized into nine genomovars, among them genomovar II and genomovar III, contain the highly epidemic strains. However, it was known that strain CF-66 is not a member of genomovar II or III of the B. cepacia complex by species-specific polymerase chain reaction assay. In this study, the antifungal compound CF66I produced by strain CF-66 was purified and characterized. Based on the nuclear magnetic resonance, GC-MS spectral and infrared spectral data, CF66I was confirmed to have amide bonds, alpha-methyl fatty acid, bromine, and some structural units such as CH(2)CH(2)O. CF66I is stable to high temperature, proteolytic enzymes, and organic solvents. CF66I inhibit the growth of a variety of plant pathogenic fungi and pathogenic yeast, whereas bacterial cells are unaffected. CF66I mainly reduced hyphal extension rates in a dose-dependent manner and induced severe change in cell morphology that resulted in swelled and formed very short hyphae with multiple branches.

Endophytic Bacteria from Pinus taeda L. as Biocontrol Agents of Fusarium circinatum Nirenberg & O'Donnell

“…have been used as biocontrol agents against fungal disease, including Fusarium spp. (Quan et al, 2006).…”

“…Burkholderia cepacia is an ubiquitous soil organism that can be easily obtained and it has been studied as biocontrol agent of plant disease (Leisinger and Margraff, 1979). Many of its metabolites have been isolated and identified thus verifying its inhibitory effect on different plant pathogens such as fungus, bacteria and yeasts (Sopheareth et al, 2006), particularly on species of Pythium, Botrytis, Fusarium, and Rhizotocnia (Sijam and Dikin, 2005;Quan et al, 2006).…”

Molecular mechanisms underlying the close association between soil Burkholderia and fungi

“…From in vitro studies, we know that Burkholderia can form either antagonistic or mutualistic interactions with fungi. Antagonistic behaviour of Burkholderia species is well described and is largely due to the production of multiple antifungal compounds (Lewenza and Sokol, 2001;Partida-Martinez and Hertweck, 2007;Schmidt et al, 2009) that can be inhibitory to a wide range of phytopathogenic fungi (Quan et al, 2006;Kilani-Feki et al, 2011;Groenhagen et al, 2013). It has been reported that many environmental Burkholderia strains have beneficial effects on fungi, suggesting symbiotic and/or mutualistic interactions.…”

Burkholderia cepacia aisladas de variedades de ñame con actividad antimicrobiana contra Colletotrichum gloeosporioides

“…Para el caso de B. cepacia, ha sido considerada una bacteria con un potencial para el control biológico de hongos fitopatógenos (JAYASWAL et al, 1990). La actividad inhibitoria de esta bacteria contra una diversidad de fitopatógenos ha sido atribuida a la producción de metabolitos secundarios como cepacina, pirrolnitrina, altericidina y otros compuestos volátiles y no volátiles aun no identificados (EL-BANNA y WINKELMANN, 1998;QUAN et al, 2006).…”