Antibacterial activity against enterovirulent Escherichia coli strains from Bacillus amyloliquefaciencs B31 and Bacillus subtilis subsp. subtilis C4. MALDI ‐TOF MS profiling and MALDI TOF/TOF MS structural analysis on lipopeptides mixtures.

AbstractIn this work twoBacillus strains isolated from honey (Bacillus subtilis subsp.subtilis C4; access code HQ828992) and from a waste of an artisanal tannery (Bacillus amyloliquefaciens B31; access code KP893752), were evaluated in order to determine their antibacterial activity against five enteropathogenicEscherichia coli strains. The number of viable cultivable cells of the different strains ofE. coli analyzed was determined by plate count. The crude cell free supernatants of bothBacillus strains exerted anti-E. coli activities, while only the lipopeptide fraction of B31 had significantE. coli inhibition. The lipopeptides produced by theBacillus were analyzed using matrix assisted laser desorption-ionization mass spectrometry (MALDI-MS). The analysis was conducted combining the profiles (fingerprints) of the lipopeptides mixture and the individual lipopeptide fragmentation (MS/MS mode), both obtained from the same lipopeptides mixture sample, for higher output. Data obtained from C4 and B31 revealed that surfactin homologues were the most abundant lipopeptides produced by both strains studied. Additionally, kurstakin, iturin and fengycin homologues were detected. Using the MS/MS mode, it was demonstrated that isobar compounds belonging to different families were produced by eachBacillus strain (e.g, C-16 bacillomycin D was detected in B31 samples, meanwhile C-15 iturin C was detected in C4). Tandem mass spectrometry MS/MS analysis contributed with relevant information ...
Source: Journal of Mass Spectrometry - Category: Chemistry Authors: Tags: RESEARCH ARTICLE Source Type: research