Literature summary for 4.1.99.2 extracted from

Milic, D.; Demidkina, T.V.; Faleev, N.G.; Phillips, R.S.; Matkovic-Calogovic, D.; Antson, A.A.
Crystallographic snapshots of tyrosine phenol-lyase show that substrate strain plays a role in C-C bond cleavage (2011), J. Am. Chem. Soc., 133, 16468-16476.

Cloned(Commentary)

Cloned (Comment)	Organism
gene tpl, expression of wild-type and mutant enzymes in Escherichia coli strain SVS 370	Citrobacter freundii

Crystallization (Commentary)

Crystallization (Comment)	Organism
purified wild-type enzyme in ternary complex with pyridine N-oxide and the L-Ala quinonoid reaction intermediate by soaking wild-type TPL crystals in the stabilization solution containing 40% w/v PEG 5000 MME, 50 mM triethanolamine, pH 8.0, 0.25 M KCl, 0.2 mM pyridoxal 5'-phosphate, 0.5 mM dithiothreitol, with 100 mM L-Ala and a saturating concentration of pyridine N-oxide for 20 s, and purified Y71F or F448H mutant enzymes with bound substrate in quinoid intermediate state by soaking the crystals in the same stabilizing solution but with addition of 10 mM 3-fluoro-L-Tyr for 30 s, X-ray diffraction structure determination and analysis at 2.05-2.25 A resolution	Citrobacter freundii

Crystallization (Comment)

Organism

purified wild-type enzyme in ternary complex with pyridine N-oxide and the L-Ala quinonoid reaction intermediate by soaking wild-type TPL crystals in the stabilization solution containing 40% w/v PEG 5000 MME, 50 mM triethanolamine, pH 8.0, 0.25 M KCl, 0.2 mM pyridoxal 5'-phosphate, 0.5 mM dithiothreitol, with 100 mM L-Ala and a saturating concentration of pyridine N-oxide for 20 s, and purified Y71F or F448H mutant enzymes with bound substrate in quinoid intermediate state by soaking the crystals in the same stabilizing solution but with addition of 10 mM 3-fluoro-L-Tyr for 30 s, X-ray diffraction structure determination and analysis at 2.05-2.25 A resolution

Citrobacter freundii

Protein Variants

Protein Variants	Comment	Organism
F448H	site-directed mutagenesis, the mutant enzyme lacks the beta-elimination activity with L-Tyr or 3-fluoro-L-tyrosine as substrates, instead, it accumulates quinonoid intermediate	Citrobacter freundii
additional information	substrate 3-fluoro-L-tyrosine is converted only to the quinoid reaction intermediate, structure determination of 3-fluoro-L-tyrosine bound to enzyme mutant Y71F with open active site and mutant F448H with closed active site, overview	Citrobacter freundii
Y71F	site-directed mutagenesis, the mutant enzyme lacks the beta-elimination activity with L-Tyr or 3-fluoro-L-tyrosine as substrates, instead, it accumulates quinonoid intermediate	Citrobacter freundii

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
L-tyrosine + H2O	Citrobacter freundii	-	phenol + pyruvate + NH3	-	r

Organism

Organism	UniProt	Comment	Textmining
Citrobacter freundii	-	-	-

Reaction

Reaction	Comment	Organism	Reaction ID
L-tyrosine + H2O = phenol + pyruvate + NH3	reversible cleavage of the Cbeta-Cgamma bond of L-tyrosine in the final stage of the beta-elimination, via intermediates: internal aldimine, external aldimine, quinoid, ketoquinoid, alpha-aminoacrylate, and internal aldimine, stepwise mechanism, overview	Citrobacter freundii	a

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
L-alanine + H2O	wild-type enzyme forms the Ala quinonoid intermediate when incubated with L-Ala	Citrobacter freundii	?	-	?
L-tyrosine + H2O	-	Citrobacter freundii	phenol + pyruvate + NH3	-	r
L-tyrosine + H2O	reversible cleavage of the Cbeta-Cgamma bond of L-tyrosine in the final stage of the beta-elimination, via intermediates: internal aldimine, external aldimine, quinoid, ketoquinoid, alpha-aminoacrylate, and internal aldimine, overview	Citrobacter freundii	phenol + pyruvate + NH3	-	r
additional information	substrate 3-fluoro-L-tyrosine is converted only to the quinoid reaction intermediate, structure determination of 3-fluoro-L-tyrosine bound to enzyme mutant Y71F with open active site and mutant F448H with closed active site, overview	Citrobacter freundii	?	-	?

Subunits

Subunits	Comment	Organism
homotetramer	TPL is a homotetramer with four active sites, two per catalytic dimer, located at the monomer-monomer interface	Citrobacter freundii

Synonyms

Synonyms	Comment	Organism
TPL	-	Citrobacter freundii

Cofactor

Cofactor	Comment	Organism	Structure
pyridoxal 5'-phosphate	dependent on	Citrobacter freundii