Isolation and characterization of a halotolerant Bacillus subtilis BBK-1 which produces three kinds of lipopeptides: bacillomycin L, plipastatin, and surfactin.
Twenty-three halotolerant and biosurfactant producing strains were collected from salty conditions in central Thailand. One of the strains designated BBK-1 produced the biosurfactants with the highest activity. BBK-1 was isolated from fermented foods and was identified as B. subtilis based on its physiological characteristics and 16S rRNA gene sequence. We show that the strain grows in media containing NaCl up to 16% (w/v) and produces biosurfactants in NaCl up to 8%. We found that B. subtilis BBK-1 produces three kinds of surface-active lipopeptides simultaneously. By their respective molecular weights and amino acid compositions, it is indicated that these lipopeptides are bacillomycin L, plipastatin, and surfactin. In order to analyze the production mechanism of lipopeptides further in the strain, a generally important biosynthetic gene encoding 4'-phosphopantetheinyl transferase was cloned and sequenced. The gene existed in a single copy in the genome and the deduced amino acid sequence was almost identical to that of Lpa-14 from B. subtilis strain RB14, which co-produces iturin A and surfactin.
Roongsawang
Niran
N
Department of Material and Life Science, Graduate School of Engineering, Osaka University, Japan.
Thaniyavarn
Jiraporn
J
Thaniyavarn
Suthep
S
Kameyama
Takayuki
T
Haruki
Mitsuru
M
Imanaka
Tadayuki
T
Morikawa
Masaaki
M
Kanaya
Shigenori
S
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D002244:Carbon / Q000378:metabolism; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005227:Fatty Acids / Q000096:biosynthesis*; D005285:Fermentation; D005516:Food Microbiology; D005798:Genes, Bacterial; D055666:Lipopeptides; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009842:Oligopeptides / Q000096:biosynthesis*; D010456:Peptides, Cyclic / Q000096:biosynthesis*; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012462:Saline Solution, Hypertonic / Q000494:pharmacology; D012623:Seawater / Q000382:microbiology; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012988:Soil Microbiology; D013045:Species Specificity; D013785:Thailand; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics; D014871:Water Microbiology
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005227:Fatty Acids; D055666:Lipopeptides; D009842:Oligopeptides; D010456:Peptides, Cyclic; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012462:Saline Solution, Hypertonic; C082662:phosphopantetheinyl transferase; C049901:plipastatin; C009365:surfactin peptide; C015015:bacillomycin L; D002244:Carbon; D017855:Transferases (Other Substituted Phosphate Groups); C021364:holo-(acyl-carrier-protein) synthase