SigL

• Description: Sigma subunit of the RNA polymerase, Sigma-54, Sigma L
  
  

Gene name	sigL
Synonyms
Essential	no
Product	RNA polymerase sigma-54 factor (sigma-L)
Function	utilization of arginin, acetoin and fructose, required for cold adaptation
MW, pI	49,5 kDa, 7.79
Gene length, protein length	1308 bp, 436 amino acids
Immediate neighbours	yvfG, yvfH
Get the DNA and protein sequences (Barbe et al., 2009)
Genetic context This image was kindly provided by SubtiList

The gene

Basic information

• Locus tag: BSU34200

Phenotypes of a mutant

The mutant is cold-sensitive and unable to use arginine as a single carbon source. PubMed

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: Binding to promoters of the -12, -24 type

• Protein family: sigma-54 factor family (according to Swiss-Prot) sigma-54 factor family

• Paralogous protein(s):

Genes/ operons controlled by SigL

acoA-acoB-acoC-acoL, rocA-rocB-rocC, rocD-rocE-rocF, rocG, levD-levE-levF-levG-sacC, ptb-bcd-buk-lpdV-bkdAA-bkdAB-bkdB

Extended information on the protein

• Kinetic information:

• Domains:
  • DNA binding domain (H-T-H motif) (324–343)
  • pron box domain (413–421)
  • 3 x Compositional bias domain (6–21),(32–53),(112–136)

• Modification:

• Cofactor(s):

• Effectors of protein activity:

• Interactions: SigL-RocR, SigL-LevR, SigL-BkdR, SigL-YplP, SigL-RpoB-RpoC

• Localization:

Database entries

• Structure:

• Swiss prot entry: P24219

• KEGG entry: [3]

Expression and regulation

• Operon:

• Sigma factor:

• Regulation: repressed by glucose (CcpA) , neg. regulated by CcpA PubMed

• Regulatory mechanism: CcpA: transcription repression, transcriptional roadblock

• Additional information:

Biological materials

• Mutant: GP146 (aphA3), available in Stülke lab

• Expression vector:

• lacZ fusion:

• GFP fusion:

• Antibody:

Labs working on this gene/protein

Michel Debarbouille, Pasteur Institute, Paris, France Homepage

References

1. Ali, N. O., Bignon, J., Rapoport, G., and Débarbouillé, M. (2001) Regulation of the acetoin catabolic pathway is controlled by sigma L in Bacillus subtilis. J. Bacteriol. 183, 2497-2504. PubMed
2. Belitsky BR, Sonenshein AL (1998) Role and regulation of Bacillus subtilis glutamate dehydrogenase genes. J Bacteriol 180:6298-6305. PubMed
3. Choi SK, Saier MH Jr: (2005) Regulation of sigL expression by the catabolite control protein CcpA involves a roadblock mechanism in Bacillus subtilis: potential connection between carbon and nitrogen metabolism. J Bacteriol , 187:6856-6861. PubMed
4. Débarbouillé M, Martin-Verstraete I, Kunst F, Rapoport G: (1991) The Bacillus subtilis sigL gene encodes an equivalent of (Sigma)54 from Gram-negative bacteria. Proc Natl Acad Sci USA , 88:9092-9096. PubMed
5. Martin-Verstraete I, Débarbouillé M, Klier A, Rapoport G: (1992) Mutagenesis of the Bacillus subtilis ‘-12, -24’ promoter of the levanase operon and evidence for the existence of an upstream activating sequence. J Mol Biol , 226:85-99. PubMed
6. Wiegeshoff et al. (2006) Sigma L is important for cold shock adaptation of Bacillus subtilis. J Bacteriol , 188: 3130-3133. PubMed