Pyk

• Description: pyruvate kinase, glycolytic enzyme
  
  

Gene name	pyk
Synonyms	pykA
Essential	no
Product	pyruvate kinase
Function	catabolic enzyme in glycolysis
Gene expression levels in SubtiExpress: pyk
Metabolic function and regulation of this protein in SubtiPathways: pyk
MW, pI	61,9 kDa, 4.88
Gene length, protein length	1755 bp, 585 amino acids
Immediate neighbours	ytzA, pfkA
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

ATP synthesis, carbon core metabolism, phosphoproteins, most abundant proteins

The gene

Basic information

• Locus tag: BSU29180

Phenotypes of a mutant

Unable to grow with non-PTS carbohydrates (such as glucitol or glycerol) as single carbon source.

Database entries

• BsubCyc: BSU29180

• DBTBS entry: [1]

• SubtiList entry: [2]

Additional information

• A mutation was found in this gene after evolution under relaxed selection for sporulation PubMed

The protein

Basic information/ Evolution

• Catalyzed reaction/ biological activity: ADP + phosphoenolpyruvate --> ATP + pyruvate
  • The reaction is irreversible under physiological conditions

• Protein family: PEP-utilizing enzyme family (according to Swiss-Prot) pyruvate kinase family, (C-terminal section: PEP-utilizing enzyme family)

• Paralogous protein(s):

Extended information on the protein

• Kinetic information:
  • allosteric Regulation PubMed
  • specific activity: 0.231 µmol min^-1 (mg protein)^-1 PubMed

• Domains:

• Modification: phosphorylation on Ser36 PubMed, PubMed, phosphorylation on Ser536 or Ser546 PubMed, please note that the Ser is not on position 536 but rather at 538

• Cofactors: Mg2+, K+

• Effectors of protein activity:
  • Activated by PEP (Hill Coefficient 1,8) PubMed PubMed
  • Allosterically activated by AMP PubMed
  • Activation by r5p and ADP PubMed
  • Inhibition by ADP and f16bp in high concentrations; and ATP PubMed

• Interactions:

• Localization: cytoplasm PubMed

Database entries

• BsubCyc: BSU29180

• Structure: 2E28 (Geobacillus stearothermophilus)

• UniProt: P80885

• KEGG entry: [3]

• E.C. number: 2.7.1.40

Additional information

The enzyme is a tetramer with four active sites PubMed

Expression and regulation

• Operon: pfkA-pyk-ytzA PubMed

• Expression browser: pyk PubMed

• Sigma factor:

• Regulation:
  • twofold induced by glucose PubMed

• Regulatory mechanism:

• Additional information:
  • belongs to the 100 most abundant proteins PubMed
  • number of protein molecules per cell (minimal medium with glucose and ammonium): 2986 PubMed
  • number of protein molecules per cell (complex medium with amino acids, without glucose): 11657 PubMed

Biological materials

• Mutant:
• GP589 (pyk::cat), available in Jörg Stülke's lab, PubMed
• GP600 (pyk::erm), available in Jörg Stülke's lab, PubMed

• Expression vector:
  • expression in E. coli, N-terminal His-tag: pGP1100 (in pWH844), available in Jörg Stülke's lab
  • expression in B. subtilis, native protein: pGP1411 (in pBQ200), available in Jörg Stülke's lab
  • expression in B. subtilis, N-terminal Strep-tag: pGP1409 (in pGP380), available in Jörg Stülke's lab
  • expression in B. subtilis, C-terminal Strep-tag: pGP1410 (in pGP382), available in Jörg Stülke's lab

• lacZ fusion: see pfkA

• GFP fusion:

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

• Antibody:

Labs working on this gene/protein

Jörg Stülke, University of Göttingen, Germany Homepage