Isolation of the Bacillus subtilis antimicrobial peptide subtilosin from the dairy product-derived Bacillus amyloliquefaciens.
OBJECTIVE
To purify and characterize an antimicrobial protein (bacteriocin) isolated from the dairy product-derived Bacillus amyloliquefaciens.


RESULTS
An unknown bacterial species cultured from the Yogu Farm probiotic dairy beverage was identified through 16S ribosomal RNA analysis as B. amyloliquefaciens, a phylogenetically close relative of Bacillus subtilis. The cell-free supernatant (CFS) of overnight cultures was active against Listeria monocytogenes and also against clinical isolates of Gardnerella vaginalis and Streptococcus agalactiae. At the same time, several isolates of vaginal probiotic Lactobacilli were resistant to the CFS. The nature of the compound causing inhibitory activity was confirmed as proteinaceous by enzymatic digestion. The protein was isolated using ammonium sulfate precipitation, and further purified via column chromatography. PCR analysis was conducted to determine relatedness to other bacteriocins produced by Bacillus spp.


CONCLUSIONS
The antimicrobial protein isolated from B. amyloliquefaciens was shown to be subtilosin, a bacteriocin previously reported as produced only by B. subtilis.


CONCLUSIONS
This is the first report of intra-species horizontal gene transfer for subtilosin and the first fully characterized bacteriocin isolated from B. amyloliquefaciens. Finally, this is the first report on subtilosin's activity against bacterial vaginosis-associated pathogens.
Sutyak
K E
KE
Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
Wirawan
R E
RE
Aroutcheva
A A
AA
Chikindas
M L
ML
D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis*; D000898:Antibiosis; D001407:Bacillus / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D001430:Bacteriocins / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods; D003611:Dairy Products / Q000382:microbiology*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005516:Food Microbiology; D006194:Gardnerella vaginalis / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability; D010456:Peptides, Cyclic / Q000032:analysis*; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D013292:Streptococcus agalactiae / Q000502:physiology; D013696:Temperature; D016585:Vaginosis, Bacterial / Q000382:microbiology
D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D010456:Peptides, Cyclic; D012336:RNA, Ribosomal, 16S; C047828:sboA protein, Bacillus subtilis