Hbs

• Description: non-specific DNA-binding protein Hbsu
  
  

Gene name	hbs
Synonyms	dbpA, hupA
Essential	yes PubMed
Product	non-specific DNA-binding protein Hbsu
Function	DNA packaging, function of the signal recognition complex
Gene expression levels in SubtiExpress: hbs
MW, pI	9 kDa, 9.501
Gene length, protein length	276 bp, 92 aa
Immediate neighbours	folE, spoIVA
Sequences	Protein DNA DNA_with_flanks
Genetic context This image was kindly provided by SubtiList
Expression at a glance   PubMed

Categories containing this gene/protein

DNA condensation/ segregation, essential genes, membrane proteins, phosphoproteins

This gene is a member of the following regulons

LexA regulon, SigH regulon

The gene

Basic information

• Locus tag: BSU22790

Phenotypes of a mutant

essential PubMed

Database entries

• BsubCyc: BSU22790

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity:
  • Hbs-mediated untwisting of the DNA stimulates Nth endonuclease activity at AP sites PubMed

• Protein family: DbpA subfamily (according to Swiss-Prot)

• Paralogous protein(s): YonN

Extended information on the protein

• Kinetic information:

• Domains:

• Modification:
  • phosphorylated on Arg-61 PubMed
  • phosphorylation on Thr-4 PubMed

• Cofactor(s):

• Effectors of protein activity:

• Interactions:

• Localization:
  • associated with the nucleoid in vegetative cells and forespores PubMed
  • membrane associated PubMed

Database entries

• BsubCyc: BSU22790

• Structure: 1HUU (Geobacillus stearothermophilus)

• UniProt: P08821

• KEGG entry: [3]

• E.C. number:

Expression and regulation

• Operon: hbs PubMed

• Expression browser: hbs PubMed

• Sigma factor: SigA PubMed, SigH PubMed

• Regulation:
  • induced by DNA damage (LexA) PubMed
  • strongly repressed in response to glucose starvation in M9 medium PubMed

• Regulatory mechanism:
  • LexA: transcription repression PubMed

• Additional information:
  • mRNA is protected from degradation by RnjA by initiating ribosomes PubMed
  • Hbs is present with about 50,000 copies per genome in vegetative cells and spores, it is one of the most abundant proteins in B. subtilis PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium): 19917 PubMed
  • number of protein molecules per cell (complex medium with amino acids, without glucose): 41521 PubMed

Biological materials

• Mutant:

• Expression vector:

• lacZ fusion:

• GFP fusion:

• two-hybrid system: B. pertussis adenylate cyclase-based bacterial two hybrid system (BACTH), available in Fabian Commichau's lab

• Antibody:

Labs working on this gene/protein

• Ciaran Condon, IBPC, Paris, France Homepage
• Mohamed Marahiel, University of Marburg, Germany Homepage

References

Reviews

Wolfgang Klein, Mohamed A Marahiel
Structure-function relationship and regulation of two Bacillus subtilis DNA-binding proteins, HBsu and AbrB.
J Mol Microbiol Biotechnol: 2002, 4(3);323-9
[PubMed:11931565] [WorldCat.org] (P p)