Dual control of subtilin biosynthesis and immunity in Bacillus subtilis.
The production of the peptide antibiotic (lantibiotic) subtilin in Bacillus subtilis ATCC 6633 is highly regulated. Transcriptional organization and regulation of the subtilin gene cluster encompassing 11 genes was characterized. Two polycistronic mRNAs encoding transcript spaBTC (6.8 kb) and encoding transcript spaIFEG (3.5 kb) as well as the monocistronic spaS (0.3 kb) mRNA were shown by Northern hybridization. Primer extension experiments and beta-galactosidase fusions confirmed three independent promoter sites preceding genes spaB, spaS and spaI. beta-Galactosidase expression of spaB, spaS and spaI promoter lacZ fusions initiated in mid-exponential growth. Maximal activities were reached at the transition to stationary growth and were collinear with subtilin production. The lacZ activity was dependent on co-expression with the two-component regulatory system spaRK. The presence of subtilin was needed for efficient expression of all three promoter lacZ fusions. This suggests a transcriptional autoregulation according to a quorum-sensing mechanism with subtilin as autoinducer and signal transduction via SpaRK. Additionally, spaR expression was found to be under positive control of the alternative sigma factor H. Deletion of sigma H strongly decreased subtilin production. Full subtilin production could be restored after in-trans complementation of spaR. Deletion of the major B. subtilis transition state regulator AbrB strongly increased subtilin production. These results show that the spaRK two-component regulatory system, and hence subtilin biosynthesis and immunity, is under dual control of two independent regulatory systems: autoinduction via subtilin and transcriptional regulation via sigma factor H.
Stein
Torsten
T
Institut für Mikrobiologie, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany.
Borchert
Stefan
S
Kiesau
Peter
P
Heinzmann
Stefan
S
Klöss
Stephan
S
Klein
Cora
C
Helfrich
Markus
M
Entian
Karl-Dieter
KD
D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics / Q000276:immunology*; D001426:Bacterial Proteins; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D017930:Genes, Reporter; D007700:Kinetics; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009876:Operon; D010455:Peptides; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D020860:Subtilisin / Q000235:genetics*; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D017931:DNA Primers; D008565:Membrane Proteins; D010455:Peptides; D012333:RNA, Messenger; C104626:SpaB protein, Bacillus subtilis; D001616:beta-Galactosidase; D020860:Subtilisin