The enzyme chorismate lyase (EC 4.1.3.40) catalyzes the first step in ubiquinone biosynthesis, the removal of pyruvate from chorismate, to yield 4-hydroxybenzoate in Escherichia coli and other Gram-negative bacteria.[1] It belongs to the family of lyases, specifically the oxo-acid-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is chorismate pyruvate-lyase (4-hydroxybenzoate-forming). Other names in common use include CL, CPL, and UbiC.

Chorismate lyase
Identifiers
EC no.4.1.3.40
CAS no.157482-18-3
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
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PMCarticles
PubMedarticles
NCBIproteins

This enzyme catalyses the chemical reaction:[2]

chorismate 4-hydroxybenzoate + pyruvate
The chorismate pyruvate lyase (CPL) catalyzed reaction.

Its activity does not require metal cofactors.[3]

Activity

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Chorismate lyase
 
chorismate lyase with product, 1.0 a resolution
Identifiers
SymbolChor_lyase
PfamPF04345
Pfam clanCL0122
InterProIPR007440
SCOP21jd3 / SCOPe / SUPFAM
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary

Catalytic activity

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  • This enzyme has an optimum pH at 7.5

Enzymatic activity

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Inhibited by:

  • Vanillate
  • 4-hydroxybenzaldehyde
  • 3-carboxylmethylaminmethyl-4-hydroxybenzoic acid
  • 4HB - ubiC is inhibited by the product of the reaction, which scientists believe serves as a control mechanism for the pathway

Pathway

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The pathway used is called the ubiquinone biosynthesis pathway, it catalyzes the first step in the biosynthesis of ubiquinone in E. coli. Ubiquinone is a lipid-soluble electron-transporting coenzyme. They are essential electron carriers in prokaryotes and are essential in aerobic organisms to achieve ATP synthesis.[4]

Nomenclature

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There are several different names for chorismate lyase. It is also called chorismate pyruvate lyase (4-hydroxybenzoate-forming) and it is also abbreviated several different ways: CPL, CL, and ubiC. It is sometimes referred to as ubiC, because that is the gene name. This enzyme belongs to the class lyases; more specifically the ox-acid-lyase or the carbon-carbon-lyases.[5]

Taxonomic lineage:

  1. bacteria → proteobacteria → gammaproteobacteria → enterobacteriales → enterobacteriaceae → escherichia → Escherichia coli

Structure

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This enzyme is a monomer. Its secondary structure contains helixes, turns, and beta-strands. It has a mass of 18,777 daltons and its sequence is 165 amino acids long.[5]

Binding sites

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  • position: 35(M)
  • position: 77(R)
  • position: 115(L)

Mutagenesis

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  • position: 91G → A; increases product inhibition by 40%. No effect on substrate affinity.
  • position: 156E → K; loss of activity

References

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  1. ^ Nichols BP, Green JM (August 1992). "Cloning and sequencing of Escherichia coli ubiC and purification of chorismate lyase". J. Bacteriol. 174 (16): 5309–16. doi:10.1128/jb.174.16.5309-5316.1992. PMC 206367. PMID 1644758.
  2. ^ "EC 4.1.3.40".
  3. ^ Siebert M, Severin K, Heide L (April 1994). "Formation of 4-hydroxybenzoate in Escherichia coli: characterization of the ubiC gene and its encoded enzyme chorismate pyruvate-lyase". Microbiology. 140 (4): 897–904. doi:10.1099/00221287-140-4-897. PMID 8012607.
  4. ^ "KEGG PATHWAY: Ubiquinone and other terpenoid-quinone biosynthesis - Reference pathway". www.genome.jp. Retrieved 2021-04-09.
  5. ^ a b "UniprotID: P26602".

Further reading

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This article incorporates text from the public domain Pfam and InterPro: IPR007440