AUTHOR=Perez Karla J. , Viana Jaime dos Santos , Lopes Fernanda C. , Pereira Jamile Q. , dos Santos Daniel M. , Oliveira Jamil S. , Velho Renata V. , Crispim Silvia M. , Nicoli Jacques R. , Brandelli Adriano , Nardi Regina M. D. 

TITLE=Bacillus spp. Isolated from Puba as a Source of Biosurfactants and Antimicrobial Lipopeptides

JOURNAL=Frontiers in Microbiology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2017.00061

DOI=10.3389/fmicb.2017.00061

ISSN=1664-302X

ABSTRACT=<p>Several products of industrial interest are produced by <italic>Bacillus</italic>, including enzymes, antibiotics, amino acids, insecticides, biosurfactants and bacteriocins. This study aimed to investigate the potential of two bacterial isolates (P5 and C3) from puba, a regional fermentation product from cassava, to produce multiple substances with antimicrobial and surface active properties. Phylogenetic analyses showed close relation of isolates P5 and C3 with <italic>Bacillus amyloliquefaciens</italic> and <italic>Bacillus thuringiensis</italic>, respectively. Notably, <italic>Bacillus</italic> sp. P5 showed antimicrobial activity against pathogens such as <italic>Listeria monocytogenes</italic> and <italic>Bacillus cereus</italic>, in addition to antifungal activity. The presence of genes encoding pre-subtilosin (<italic>sboA</italic>), malonyl CoA transacylase <italic>(ituD)</italic>, and the putative transcriptional terminator of surfactin (<italic>sfp</italic>) were detected in <italic>Bacillus</italic> sp. P5, suggesting the production of the bacteriocin subtilosin A and the lipopeptides iturin A and surfactin by this strain. For <italic>Bacillus</italic> sp. C3 the presence of <italic>sboA</italic> and <italic>spas</italic> (subtilin) genes was observed by the first time in members of <italic>B. cereus</italic> cluster. <italic>Bacillus</italic> sp. P5 showed emulsifying capability on mineral oil, soybean biodiesel and toluene, while <italic>Bacillus</italic> sp. C3 showed emulsifying capability only on mineral oil. The reduction of the surface tension in culture medium was also observed for strain P5, confirming the production of surface-active compounds by this bacterium. Monoprotonated molecular species and adducts of sodium and potassium ions of surfactin, iturin, and fengycin were detected in the P5 culture medium. Comparative MS/MS spectra of the peak <italic>m/z</italic> 1030 (C14 surfactin A or C15 surfactin B [M+Na]<sup>+</sup>) and peak <italic>m/z</italic> 1079 (C15 iturin [M+Na]<sup>+</sup>) showed the same fragmentation profile of standards, confirming the molecular identification. In conclusion, <italic>Bacillus</italic> sp. P5 showed the best potential for the production of antifungal, antibacterial, and biosurfactant substances.</p>