InfB

• Description: translation initiation factor IF-2
  
  

Gene name	infB
Synonyms
Essential	yes PubMed
Product	initiation factor IF-2
Function	translation
MW, pI	78 kDa, 5.191
Gene length, protein length	2148 bp, 716 aa
Immediate neighbours	ylxQ, ylxP
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: BSU16630

Phenotypes of a mutant

essential PubMed

Database entries

• DBTBS entry: [1]

• SubtiList entry: [2]

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: Initiation of translation

• Protein family: IF-2 family (according to Swiss-Prot)

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:

• Domains: Nucleotide-binding domain that competitively binds GTP or ppGpp PubMed

• Modification:

• Cofactor(s):

• Effectors of protein activity: GTP or ppGpp PubMed

• Interactions:

• Localization: cytoplasm (according to Swiss-Prot)

Database entries

• Structure: 1D1N (fMet-tRNA-fMet binding domain, Geobacillus stearothermophilus), 1Z9B (C1-subdomain, Geobacillus stearothermophilus)

• UniProt: P17889

• KEGG entry: [3]

• E.C. number:

Expression and regulation

• Operon: ylxS-nusA-ylxR-ylxQ-infB-ylxP-rbfA PubMed

• Sigma factor: SigA PubMed

• Regulation:
  • RelA dependent downregulation (Class I) during stringent response PubMed
  • Interaction with ppGpp interferes with IF2-dependent initiation complex formation, severely inhibits initiation dipeptide formation, and blocks the initiation step of translation.PubMed

• Regulatory mechanism:

• Additional information: Putative cellular metabolic sensor and regulator that oscillates between an active GTP-bound form under conditions allowing active protein syntheses and an inactive ppGpp-bound form when depleting of nutrients PubMed

Biological materials

• Mutant:

• Expression vector:

• lacZ fusion:

• GFP fusion:

• two-hybrid system:

• Antibody:

References

Pohl Milon, Eugene Tischenko, Jerneja Tomsic, Enrico Caserta, Gert Folkers, Anna La Teana, Marina V Rodnina, Cynthia L Pon, Rolf Boelens, Claudio O Gualerzi
The nucleotide-binding site of bacterial translation initiation factor 2 (IF2) as a metabolic sensor.
Proc Natl Acad Sci U S A: 2006, 103(38);13962-7
[PubMed:16968770] [WorldCat.org] [DOI] (P p)

Christine Eymann, Georg Homuth, Christian Scharf, Michael Hecker
Bacillus subtilis functional genomics: global characterization of the stringent response by proteome and transcriptome analysis.
J Bacteriol: 2002, 184(9);2500-20
[PubMed:11948165] [WorldCat.org] [DOI] (P p)

K Shazand, J Tucker, M Grunberg-Manago, J C Rabinowitz, T Leighton
Similar organization of the nusA-infB operon in Bacillus subtilis and Escherichia coli.
J Bacteriol: 1993, 175(10);2880-7
[PubMed:8491709] [WorldCat.org] [DOI] (P p)