Hosta

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.

This enzyme catalyses the chemical reaction:^[2]

chorismate

\rightleftharpoons

4-hydroxybenzoate + pyruvate

Its activity does not require metal cofactors.^[3]

Activity

Catalytic activity

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 synthesis.^[4]

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.^[5]

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 and its sequence is 165 amino acids long.^[5]

Binding sites

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

Mutagenesis

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

References

^ 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.
^ "EC 4.1.3.40".
^ 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.
^ "KEGG PATHWAY: Ubiquinone and other terpenoid-quinone biosynthesis - Reference pathway". www.genome.jp. Retrieved 2021-04-09.
^ ^a ^b "UniprotID: P26602".

Nichols BP, Green JM (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.
Siebert M, Severin K, Heide L (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.
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

[pmid1644758-1] 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".

[pmid8012607-3] 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.

[:0-5] "UniprotID: P26602".

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Carbon–carbon lyases (EC 4.1)
4.1.1: Carboxy-lyases	Acetoacetate decarboxylase Adenosylmethionine decarboxylase Arginine decarboxylase Aromatic L-amino acid decarboxylase Glutamate decarboxylase Histidine decarboxylase Lysine decarboxylase Malonyl-CoA decarboxylase Ornithine decarboxylase Oxaloacetate decarboxylase Phosphoenolpyruvate carboxykinase Phosphoenolpyruvate carboxylase Phosphoribosylaminoimidazole carboxylase Pyrophosphomevalonate decarboxylase Pyruvate decarboxylase RuBisCO Uridine monophosphate synthetase/Orotidine 5'-phosphate decarboxylase Uroporphyrinogen III decarboxylase
4.1.2: Aldehyde-lyases	Fructose-bisphosphate aldolase Aldolase A Aldolase B Aldolase C 2-hydroxyphytanoyl-CoA lyase Threonine aldolase
4.1.3: Oxo-acid-lyases	Isocitrate lyase 3-hydroxy-3-methylglutaryl-CoA lyase
4.1.99: Other	Tryptophanase Photolyase CPD lyase Spore photoproduct lyase

Enzymes
Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Diffusion-limited enzyme Cofactor Enzyme catalysis
Regulation	Allosteric regulation Cooperativity Enzyme inhibitor Enzyme activator
Classification	EC number Enzyme superfamily Enzyme family List of enzymes
Kinetics	Enzyme kinetics Eadie–Hofstee diagram Hanes–Woolf plot Lineweaver–Burk plot Michaelis–Menten kinetics
Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list) EC7 Translocases (list)