Table 1.
Bacterial strains used in this study.
Fig 1.
Antimicrobial activity of Br. Laterosporus BGSP7 (1), BGSP9 (2), BGSP11 (3) and BGSP12 (4) strains on different indicator strains: S. aureus ATCC25923 (A); L. monocytogenes ATCC19111 (B); P. aeruginosa MMA83 (C); K. pneumoniae Ni9 (D).
Antimicrobial activity was analysed after overnight growth (16 h) of the indicator strains.
Fig 2.
Antimicrobial activity of Br. laterosporus BGSP7 (1), BGSP9 (2) and BGSP11 (3) strains on S. aureus ATCC25923 incubated for three days (A); Development of specific structures to over-bridge zone of inhibition by Br. laterosporus BGSP11 strain in antimicrobial assay with Br. laterosporus strain BGSP7 (1), BGAP9 (2) and BGSP11 (3) on sensitive strain S. aureus ATCC25923.
Negative control (4) used in antimicrobial test: S. aureus ATCC25923. Parts showing the antimicrobial activity of the strains were taken from the same Petri dish that was incubated for five days (B).
Fig 3.
Macrorestriction pattern analysis by pulsed field gel electrophoresis (PFGE) of Br. laterosporus BGSP7, BGSP9, BGSP11 and BGSP12 strains using NotI restriction enzyme on 1.2% agarose gel.
Fig 4.
Kinetics of antimicrobial production of Br. laterosorus BGSP7 (A), BGSP9 (B) and BGSP11 (C) strains during the growth in LB medium at 37°C.
Growth of analyzed strains was monitored by measuring optical density at OD600 (▲); Synthesis of antimicrobials was quantified by growth inhibition of S. aureus ATCC25923 (●) and P. aeruginosa MMA83 (◆) by producer strains measured in millimeters of inhibition zone (mm).
Fig 5.
SDS-PAGE gel electrophoresis of proteins precipitated from supernatant of Br. laterosporus BGSP7, BGSP9, BGSP11 and BGSP12 strains on 15% acrylamide gel stained with Coomassie Brilliant Blue (A); gel with the same samples overlayed with LA-soft agar containing S. aureus ATCC25923 after incubation overnight at 37°C (B).
Table 2.
Amino acids analysis of antimicrobial peptides purified by RP-HPLC from BGSP7 and BGSP11 strains.
Results are presented in percent (%).
Table 3.
Minimal inhibitory concentrations (MICs).
Table 4.
Summary statistics for genome sequence assemblies.
Table 5.
Genome-based identification of novel molecules with antimicrobial activity by bioinformatic tools (AntiSMASH and BAGEL3).
Table 6.
Synthase genes present in genomes of Br. laterosporus BGSP7, BGSP9 and BGSP11 strains.
Fig 6.
Comparative analysis of brevibacillin gene cluster among Brevibacillus laterosporus strains.
brvA—brevibacillin synthetase A, brvB—brevibacillin synthetase B, brvC—brevibacillin synthetase C, brvD—brevibacillin synthetase D, brvE—brevibacillin synthetase E, and brvF—brevibacillin ABC-transporter F genes.
Fig 7.
Bacteriocin gene transcription analysis of Br. laterosporus BGSP7 (A); BGSP9 (B) and BGSP11 (C) by RT-qPCR.