mycosubtiline and fengycin

Bacillus subtilis currently encompasses four subspecies, Bacillus subtilis subsp. subtilis, Bacillus subtilis subsp. inaquosorum, Bacillus subtilis subsp. spizizenii and Bacillus subtilis subsp. stercoris. Several studies based on genomic comparisons have suggested these subspecies should be promoted to species status. Previously, one of the main reasons for leaving them as subspecies was the lack of distinguishing phenotypes. In this study, we used comparative genomics to determine the genes unique to each subspecies and used these to lead us to the unique phenotypes. The results show that one difference among the subspecies is they produce different bioactive secondary metabolites. B. subtilis subsp. spizizenii is shown conserve the genes to produce mycosubtilin, bacillaene and 3,3'-neotrehalosadiamine. B. subtilis subsp. inaquosorum is shown conserve the genes to produce bacillomycin F, fengycin and an unknown PKS/NRPS cluster. B. subtilis subsp. stercoris is shown conserve the genes to produce fengycin and an unknown PKS/NRPS cluster. While B. subtilis subsp. subtilis is shown to conserve the genes to produce 3,3'-neotrehalosadiamine. In addition, we update the chemotaxonomy and phenotyping to support their promotion to species status.

Topics: Bacillus subtilis; Genome, Bacterial; Lipopeptides; Lipoproteins; Peptides, Cyclic; Polyenes

In this study, we have investigated the effects of three lipopeptides (fengycin, surfactin and mycosubtilin) produced by different strains of Bacillus subtilis against the phytopathogenic fungi Fusarium oxysporum f. sp. iridacearum, which affects the ornamental bulb plant populations of Iris sp. The antifungal effects were tested using minimum inhibitory concentration assay, determination of mycelium growth and spore germination inhibition rates. Also, in vivo tests on infected rhizomes and scanning electron microscopy were employed. Mycosubtilin alone and in combination with fengycin or/and surfactin showed potent inhibitory activity at concentrations as low as 5 μg ml

Topics: Bacillus subtilis; Biological Control Agents; Fusarium; Lipopeptides; Lipoproteins; Microbial Sensitivity Tests; Mycelium; Plant Diseases

Topics: Bacterial Proteins; Carrier Proteins; Catalytic Domain; Chromatography, High Pressure Liquid; Cyclization; Escherichia coli; Kinetics; Lipopeptides; Lipoproteins; Multienzyme Complexes; Peptide Synthases; Peptides; Peptides, Cyclic; Phenols; Protein Subunits; Recombinant Proteins; Spectrometry, Mass, Electrospray Ionization; Stereoisomerism; Substrate Specificity; Sulfhydryl Compounds; Thiolester Hydrolases