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

• Published in: Frontiers in microbiology Vol. 8; p. 61
• Main Authors: 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
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 31-01-2017
• Subjects: Microbiology; MALDI-TOF mass spectrometry; fermented food; Bacillus spp; antimicrobial peptides; biosurfactant; cassava
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2017.00061

Several products of industrial interest are produced by
, 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
and
, respectively. Notably,
sp. P5 showed antimicrobial activity against pathogens such as
and
, in addition to antifungal activity. The presence of genes encoding pre-subtilosin (
), malonyl CoA transacylase
, and the putative transcriptional terminator of surfactin (
) were detected in
sp. P5, suggesting the production of the bacteriocin subtilosin A and the lipopeptides iturin A and surfactin by this strain. For
sp. C3 the presence of
and
(subtilin) genes was observed by the first time in members of
cluster.
sp. P5 showed emulsifying capability on mineral oil, soybean biodiesel and toluene, while
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
1030 (C14 surfactin A or C15 surfactin B [M+Na]
) and peak
1079 (C15 iturin [M+Na]
) showed the same fragmentation profile of standards, confirming the molecular identification. In conclusion,
sp. P5 showed the best potential for the production of antifungal, antibacterial, and biosurfactant substances.