Bacillus amyloliquefaciens—Derived Lipopeptide Biosurfactants Inhibit Biofilm Formation and Expression of Biofilm-Related Genes of Staphylococcus aureus

Abstract

Biosurfactants (BSs) are surface-active compounds produced by diverse microorganisms, including the genus Bacillus. These bioactive compounds possess biological activities such as antiadhesive, antimicrobial and antibiofilm effects that can lead to important applications in combating many infections. Based on these findings, we decided to investigate the antibiofilm activity of BSs from the marine Bacillus amyloliquefaciens against Staphylococcus aureus CCM 4223. Expression of biofilm-related genes was also evaluated using qRT-PCR. Isolated and partially purified BSs were identified and characterized by molecular tools and by UHPLC-DAD and MALDI-TOF/MS. Bacillus amyloliquefaciens 3/22, that exhibited surfactant activity evaluated by oil spreading assay, was characterized using the 16S rRNA sequencing method. Screening by PCR detected the presence of the sfp, srfAA, fenD and ituD genes, suggesting production of the lipopeptides (LPs) surfactin, fengycin and iturin. The above findings were further supported by the results of UHPLC-DAD and MALDI-TOF/MS. As quantified by the crystal violet method, the LPs significantly (p < 0.001) reduced biofilm formation of S. aureus in a dose-dependent manner and decreased expression of biofilm-related genes fnbA, fnbB, sortaseA and icaADBC operon. Data from our investigation indicate a promising therapeutic application for LPs isolated from B. amyloliquefaciens toward prevention of S. aureus biofilm infections.

Mass Spectral Molecular Networking to Profile the Metabolome of Biostimulant Bacillus Strains

“…The pursuit of discovering and exploring Bacillus lipopeptides has long been an attractive undertaking for scientists and industry researchers due to its various applications such as interference with flagella development, affecting the bacterial adhesion, inhibition of biofilm formation and disruption of pre-formed biofilms ( Hu et al, 2019 ; Englerová et al, 2021 ). Moreover, the bioactivity of lipopeptides comes from the capability of these cyclic compounds to disrupt the structures and functions of bio-membranes, which improves membrane permeability—one of the key factors important in Bacillus -plant chemical intercommunication ( Bernat et al, 2016 ).…”

Metabolomic Insights of Biosurfactant Activity from Bacillus niabensis against Planktonic Cells and Biofilm of Pseudomonas stutzeri Involved in Marine Biofouling

“…This group of compounds had the ability to completely inhibit S. aureus biofilm formation at the concentration of 15 mg/mL. Furthermore, they reduced biofilm formation by 50% at concentrations of 1.5 and 0.15 mg/mL [ 47 ].…”

“…BS are a promising antibiofilm and antifouling molecules due to their low toxicity [ 40 ], their mode of action (e.g., modulation of the expression of biofilm genes) [ 47 , 50 ] and their amphiphilic nature (that allows them disrupt membrane integrity, leading to cell lysis, linked with the ability to affect adhesion and dislodgement of bacteria from the surface) [ 51 , 52 ]. They can also promote changes in membrane structure, altering the essential membrane structure such as the transport and production of energy [ 53 ].…”

Mass spectral molecular networking to decode the chemical space of biostimulant Bacillus strains

“…The pursuit of discovering and exploring Bacillus lipopeptides has long been an attractive undertaking for scientists and industry researchers due to its various applications such as interference with agella development, affecting the bacterial adhesion, inhibition of bio lm formation and disruption of preformed bio lms 23,24 . Moreover, the bioactivity of lipopeptides comes from the capability of these cyclic compounds to disrupt the structures and functions of bio-membranes, which improves membrane permeability -one of the key factors important in Bacillus-plant chemical intercommunication 18 .…”