Literature summary for 4.2.99.21 extracted from

Olucha, J.; Ouellette, A.N.; Luo, Q.; Lamb, A.L.
pH Dependence of catalysis by Pseudomonas aeruginosa isochorismate-pyruvate lyase: implications for transition state stabilization and the role of lysine 42 (2011), Biochemistry, 50, 7198-7207.

Search for more literature for 4.2.99.21

Crystallization (Commentary)

Crystallization (Comment)	Organism
purified recombinant His-tagged wild-type enzyme and mutant K42E in complex with salicylate and pyruvate, hanging drop vapor diffusion method, mixing of 0.001 ml of 64 mg/ml wild-type protein with 0.001 ml of reservoir solution containing 0.2 M lithium sulfate, 0.1 M sodium acetate, pH 4.5, and 6% glycerol, mixing of 0.001 ml of 34 mg/ml mutant protein with 0.001 ml reservoir solution containing 0.004 M Gly-Gly, 0.100 M sodium acetate, pH 3.6, and 12% glycerol, ligands in 20fold molar excess, 25°C, 24-48 h, X-ray diffraction structure determination and analysis, modeling	Pseudomonas aeruginosa
wild-type and mutant K42E, to 1.95 and 1.79 A resolution, respectively, in complex with salicylate and pyruvate	Pseudomonas aeruginosa

Crystallization (Comment)

Organism

purified recombinant His-tagged wild-type enzyme and mutant K42E in complex with salicylate and pyruvate, hanging drop vapor diffusion method, mixing of 0.001 ml of 64 mg/ml wild-type protein with 0.001 ml of reservoir solution containing 0.2 M lithium sulfate, 0.1 M sodium acetate, pH 4.5, and 6% glycerol, mixing of 0.001 ml of 34 mg/ml mutant protein with 0.001 ml reservoir solution containing 0.004 M Gly-Gly, 0.100 M sodium acetate, pH 3.6, and 12% glycerol, ligands in 20fold molar excess, 25°C, 24-48 h, X-ray diffraction structure determination and analysis, modeling

Pseudomonas aeruginosa

wild-type and mutant K42E, to 1.95 and 1.79 A resolution, respectively, in complex with salicylate and pyruvate

Pseudomonas aeruginosa

Protein Variants

Protein Variants	Comment	Organism
K42A	similar to wild-type, active across the entire pH-range from 4 to 9, with a constant level of activity at pH 5 and above	Pseudomonas aeruginosa
K42A	site-directed mutagenesis of the catalytic residue	Pseudomonas aeruginosa
K42E	no detectable activity at any pH tested	Pseudomonas aeruginosa
K42E	site-directed mutagenesis of the catalytic residue, inactive mutant, crystal structure determination and comparison to the wild-type structure	Pseudomonas aeruginosa
K42H	the enzyme develops a pH dependence corresponding to a loss of catalytic power upon deprotonation of the histidine. With loss of the positive charge on the K42H side chain at high pH, the enzyme retains lyase activity at about 100fold lowered catalytic efficiency but loses detectable chorismate mutase activity	Pseudomonas aeruginosa
K42H	site-directed mutagenesis of the catalytic residue, the mutant enzyme shows 100fold lowered isochorismate lyase catalytic efficiency compared to the wild-type, but loses detectable mutase activity. It develops a pH-dependence corresponding to a loss of catalytic power upon deprotonation of the histidine. The change is not due to changes in active site architecture, but due to the difference in charge at this key site	Pseudomonas aeruginosa

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
isochorismate	Pseudomonas aeruginosa	-	salicylate + pyruvate	-	?

Organism

Organism	UniProt	Comment	Textmining
Pseudomonas aeruginosa	Q51507	isochorismate-pyruvate lyase with additional chorismate mutase activity	-
Pseudomonas aeruginosa	Q51507	gene pchB	-

Reaction

Reaction	Comment	Organism	Reaction ID
isochorismate = salicylate + pyruvate	the enzyme achieves catalysis of both pericyclic reactions, isochorismate-pyruvate lyase and chorismate-pyruvate lyase, EC 4.1.3.40, in part by the stabilization of reactive conformations and in part by electrostatic transition-state stabilization. Both, substrate organization and electrostatic transition state stabilization, contribute to catalysis	Pseudomonas aeruginosa	a

Source Tissue

Source Tissue	Comment	Organism	Textmining

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
isochorismate	-	Pseudomonas aeruginosa	salicylate + pyruvate	-	?
isochorismate	elimination of pyruvate	Pseudomonas aeruginosa	salicylate + pyruvate	-	?
additional information	PchB can also perform a nonphysiological role as a chorismate mutase albeit with considerably lower catalytic efficiency	Pseudomonas aeruginosa	?	-	?

Synonyms

Synonyms	Comment	Organism
isochorismate-pyruvate lyase	-	Pseudomonas aeruginosa
PchB	-	Pseudomonas aeruginosa

Temperature Optimum [°C]

Temperature Optimum [°C]	Temperature Optimum Maximum [°C]	Comment	Organism
25	-	assay at	Pseudomonas aeruginosa

pH Range

pH Minimum	pH Maximum	Comment	Organism
4	9	active across the entire pH-range from 4 to 9, with a constant level of activity at pH 5 and above	Pseudomonas aeruginosa
4	9	activity range, pH profiles of recombinant wild-type and K42 mutant enzymes, overview	Pseudomonas aeruginosa