Chorismate lyase

In enzymology, a chorismate lyase (EC 4.1.3.40) is an enzyme that catalyzes the chemical reaction

Chorismate lyase
Identifiers
EC no.	4.1.3.40
CAS no.	157482-18-3
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

chorismate $\rightleftharpoons$ 4-hydroxybenzoate + pyruvate

The chorismate pyruvate lyase (CPL) catalyzed reaction.

Hence, this enzyme has one substrate, chorismate, and two products, 4-hydroxybenzoate and pyruvate.

This enzyme 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.

This enzyme catalyses the first step in ubiquinone biosynthesis, the removal of pyruvate from chorismate, to yield 4-hydroxybenzoate in Escherichia coli and other Gram-negative bacteria. Its activity does not require metal cofactors.

Activity

Chorismate lyase
chorismate lyase with product, 1.0 a resolution
Identifiers
Symbol	Chor_lyase
Pfam	PF04345
Pfam clan	CL0122
InterPro	IPR007440
SCOP2	1jd3 / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Catalytic activity

• Chorismate = 4HB + pyruvate
• This enzyme has an optimum pH at 7.5

Enzymatic activity

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

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.[1]

Nomenclature

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.

• • taxonomic lineage: bacteria → proteobacteria → gammaproteobacteria → enterobacteriales → enterobacteriaceae → escherichia → escherichia coli

Structure

This enzyme is a monomer. Its secondary structure contains helixes, turns, and beta strands.

• It has a mass of 18,777 daltons
• Its sequence is 165 amino acids long

Binding sites

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

Mutagenesis

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

Further reading

• Nichols BP, Green JM (1992). "Cloning and sequencing of Escherichia coli ubiC and purification of chorismate lyase". J. Bacteriol. 174 (16): 5309–16. PMC 206367. PMID 1644758.
• Siebert M, Severin K, Heide L. "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.{{cite journal}}: CS1 maint: unflagged free DOI (link)
• Meganathan R (2001). "Ubiquinone biosynthesis in microorganisms". FEMS Microbiol. Lett. 203 (2): 131–9. doi:10.1111/j.1574-6968.2001.tb10831.x. PMID 11583838.

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