Isolation and Characterization of Leu⁷-Surfactin from the Endophytic Bacterium Bacillus mojavensis RRC 101, a Biocontrol Agent for Fusarium verticillioides

Abstract

Bacillus mojavensis is an endophytic bacterium patented for control of fungal diseases in maize and other plants. Culture extracts and filtrates from this bacterium were antagonistic to the pathogenic and mycotoxic fungus Fusarium verticillioides. However, the identity of the inhibitory substance from extracts of this bacterium has not been determined. An HPLC-MS analysis of the culture filtrate showed a major ion peak that was identified as a cyclic lipopeptide. Furthermore, collisional ion dissociation (CID) analysis indicated that this lipopeptide was surfactin, a cyclic heptapeptide linked to a β-hydroxy fatty acid. A CID analysis of the peptide moiety was established by deduction and indicated that the peptide sequence consisted of two acidic amino acids and five hydrophobic amino acids with a sequence of Leu-Leu-Asp-Val-Leu-Leu-Glu. These spectra indicated that this bacterium produced Leu(7)-surfactin, which was toxic to F. verticillioides. Production of this cyclic lipopeptide is a characteristic of several species of Bacillus, but this is the first report of this very powerful biosurfactant from this endophytic species.

Isolation and characterization of a new iturinic lipopeptide, mojavensin A produced by a marine-derived bacterium Bacillus mojavensis B0621A

“…24 A Leu 7 -surfactin antagonistic to F. verticillioides has also been reported. 25 Mojavensin A produced by Bacillus mojavensis B0621A Zongwang Ma et al Fumonisin, especially fumonisin B 1 , can increase the incidence of neural tube defects and inhibit eukaryotic protein synthesis, and it can also be a potential threat to human health. 26,27 In vitro antifungal experiments indicated that anteiso-C15 mojavensin A (1) and the two fengycins (2 and 3) had dose-dependent antagonistic activity against F. verticillioides and other phytopathogens.…”

Isolation, Screening and Functional Characterization of Biosurfactant Producing Bacteria Isolated from Crude Oil Contaminated Site

“…The biosurfactant produced by microbes are helpful in bioremediation of heavy metal, pesticides and hydrocarbon contaminated sites (Juwarkar et al, 2008). They are also used as biocontrol agent to protect plant against various diseases resulting in higher crop yields (Asaka and Shoda, 1996;Krishnayya and Grewal, 2002;Gravel et al, 2005;Snook et al, 2009;Hultberg et al, 2010). Based on their functional characteristics they have much more potential to be used in agriculture i.e.…”

Purification and Structural Analysis of Surfactin Produced by Endophytic Bacillus subtilis EBS05 and its Antagonistic Activity Against Rhizoctonia cerealis

“…A series of b-and y-type ions were detected, and a peptide sequence was deducted from this CID spectrum by MassBioLynx-Peptide Sequencing. Seven amino acids (Glu-Leu-Leu-Val-Asp-Leu-Leu) were determined by ESI-MS/MS in four precursor ions (figures of ESI-MS-MS spectra of the precursor ion not shown), agreeing with the CID fragmentation of the surfactin standard (Lim et al, 2005;Snook et al, 2009). The patterns of m/z 1058.31 [M+Na] + of y-Max, determined by ESI-MS mass spectrometry, are shown in Fig.…”

“…Its mode of action is based on its detergent-like activity in dissolving several types of lipid membranes (Snook et al, 2009). B. subtilis strain can modulate host resistance associated with differential gene expression in tomatoes and cucumbers and can trigger the plant defense machinery to enhance resistance to fungal pathogen ingress.…”