Title Cyclic Lipopeptide Profile of Three Bacillus subtilis Strains; Antagonists of Fusarium Head Blight
Author Christopher A. Dunlap1*, David A. Schisler1, Neil P. Price2, and Steven F. Vaughn3
Address 1Crop Bioprotection, Research Units, National Center for Agricultural Utilization Research, Agricultural Research Service, USA, 2Bioproduct and Biocatalysis, Research Units, National Center for Agricultural Utilization Research, Agricultural Research Service, USA, 3New Crops and Processing, Research Units, National Center for Agricultural Utilization Research, Agricultural Research Service, USA
Bibliography Journal of Microbiology, 49(4),603-609, 2011,
DOI
Key Words Bacillus, iturin, fengycin, wheat, biocontrol, lipopeptides
Abstract The objective of the study was to identify the lipopetides associated with three Bacillus subtilis strains. The strains are antagonists of Gibberella zeae, and have been shown to be effective in reducing Fusarium head blight in wheat. The lipopeptide profile of three B. subtilis strains (AS43.3, AS43.4, and OH131.1) was determined using mass spectroscopy. Strains AS43.3 and AS43.4 produced the anti-fungal lipopeptides from the iturin and fengycin family during the stationary growth phase. All three strains produced the lipopeptide surfactin at different growth times. Strain OH131.1 only produced surfactin under these conditions. The antifungal activity of the culture supernatant and individual lipopeptides was determined by the inhibition of G. zeae. Cell-free supernatant from strains AS43.3 and AS43.4 demonstrated strong antibiosis of G. zeae, while strain OH131.1 had no antibiosis activity. These results suggest a different mechanism of antagonism for strain OH131.1, relative to AS43.3 and AS43.4.