Genes controlled by the essential YycG/YycF two-component system of Bacillus subtilis revealed through a novel hybrid regulator approach.
The YycG/YycF two-component system, originally identified in Bacillus subtilis, is very highly conserved and appears to be specific to low G + C Gram-positive bacteria. This system is required for cell viability, although the basis for this and the nature of the YycF regulon remained elusive. Using a combined hybrid regulator/transcriptome approach involving the inducible expression of a PhoP'-'YycF chimerical protein in B. subtilis, we have shown that expression of yocH, which encodes a potential autolysin, is specifically activated by YycF. Gel mobility shift and DNase I footprinting assays were used to show direct binding in vitro of purified YycF to the regulatory regions of yocH as well as ftsAZ, previously reported to be controlled by YycF. Nucleotide sequence analysis and site-directed mutagenesis allowed us to define a potential consensus recognition sequence for the YycF response regulator, composed of two direct repeats: 5'-TGT A/T A A/T/C-N5-TGT A/T A A/T/C-3'. A DNA-motif analysis indicates that there are potentially up to 10 genes within the B. subtilis YycG/YycF regulon, mainly involved in cell wall metabolism and membrane protein synthesis. Among these, YycF was shown to bind directly to the region upstream from the ykvT gene, encoding a potential cell wall hydrolase, and the intergenic region of the tagAB/tagDEF divergon, encoding essential components of teichoic acid biosynthesis. Definition of a potential YycF recognition sequence allowed us to identify likely members of the YycF regulon in other low G + C Gram-positive bacteria, including several pathogens such as Listeria monocytogenes, Staphylococcus aureus and Streptococcus pneumoniae.
Howell
Alistair
A
Department of Genetics, Smurfit Institute, Trinity College Dublin, Dublin 2, Ireland.
Dubrac
Sarah
S
Andersen
Kasper Krogh
KK
Noone
David
D
Fert
Juliette
J
Msadek
Tarek
T
Devine
Kevin
K
D001412:Bacillus subtilis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001483:Base Sequence; D015152:Blotting, Northern; D002473:Cell Wall / Q000235:genetics / Q000378:metabolism; D003598:Cytoskeletal Proteins; D018983:DNA Footprinting; D024202:Electrophoretic Mobility Shift Assay; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006094:Gram-Positive Bacteria / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009238:N-Acetylmuramoyl-L-alanine Amidase / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification / Q000378:metabolism; D018085:Regulon; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; C071525:FtsZ protein, Bacteria; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; C119939:YycF protein, Bacteria; C061279:PhoR protein, Bacteria; D011494:Protein Kinases; D009238:N-Acetylmuramoyl-L-alanine Amidase