EC Explorer

EC 4.3.1.19 Details
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EC number
4.3.1.19
Accepted name
threonine ammonia-lyase
Reaction
L-threonine = 2-oxobutanoate + NH3 (overall reaction);;(1a) L-threonine = 2-aminobut-2-enoate + H2O;;(1b) 2-aminobut-2-enoate = 2-iminobutanoate (spontaneous);;(1c) 2-iminobutanoate + H2O = 2-oxobutanoate + NH3 (spontaneous)
Other name(s)
threonine deaminase, L-serine dehydratase, serine deaminase, L-threonine dehydratase, threonine dehydrase, L-threonine deaminase, threonine dehydratase, L-threonine hydro-lyase (deaminating), L-threonine ammonia-lyase
Systematic name
L-threonine ammonia-lyase (2-oxobutanoate-forming)
CAS registry number
774231-81-1
Comment
Most enzymes that catalyse this reaction are pyridoxal-phosphate-dependent, although some enzymes contain an iron-sulfur cluster instead. The reaction catalysed by both types of enzymes involves the initial elimination of water to form an enamine intermediate (hence the enzyme’s original classification as EC 4.2.1.16, threonine dehydratase), followed by tautomerization to an imine form and hydrolysis of the C-N bond [3,5]. The latter reaction, which can occur spontaneously, is also be catalysed by EC 3.5.99.10, 2-iminobutanoate/2-iminopropanoate deaminase [5]. The enzymes from a number of sources also act on L-serine, cf. EC 4.3.1.17, L-serine ammonia-lyase.
History
created 1961 as EC 4.2.1.16, transferred 2001 to EC 4.3.1.19, modified 2014
EC Browser
1 Oxidoreductases (9574 organisms) download 3054352 sequences with EC number 1 in fasta format download 3054352 sequences with EC number 1 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 1) as tabstop separated file
2 Transferases (6645 organisms) download 7349866 sequences with EC number 2 in fasta format download 7349866 sequences with EC number 2 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 2) as tabstop separated file
3 Hydrolases (11217 organisms) download 3878676 sequences with EC number 3 in fasta format download 3878676 sequences with EC number 3 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 3) as tabstop separated file
4 Lyases (5132 organisms) download 2266429 sequences with EC number 4 in fasta format download 2266429 sequences with EC number 4 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4) as tabstop separated file
4.1 Carbon-carbon lyases (2543 organisms) download 801574 sequences with EC number 4.1 in fasta format download 801574 sequences with EC number 4.1 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.1) as tabstop separated file
4.2 Carbon-oxygen lyases (2355 organisms) download 972685 sequences with EC number 4.2 in fasta format download 972685 sequences with EC number 4.2 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.2) as tabstop separated file
4.3.1 Ammonia-lyases (406 organisms) download 115809 sequences with EC number 4.3.1 in fasta format download 115809 sequences with EC number 4.3.1 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.3.1) as tabstop separated file
4.3.1.8 created 1972, modified 1982, modified 1989, deleted 2003 show the reaction
4.3.1.21 created 1965 as EC 4.2.1.26, transferred 2002 to EC 4.3.1.21, deleted 2004 show the reaction
4.3.2 Amidine-lyases (89 organisms) download 133212 sequences with EC number 4.3.2 in fasta format download 133212 sequences with EC number 4.3.2 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.3.2) as tabstop separated file
4.3.3 Amine-lyases (105 organisms) download 60159 sequences with EC number 4.3.3 in fasta format download 60159 sequences with EC number 4.3.3 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.3.3) as tabstop separated file
4.4 Carbon-sulfur lyases (599 organisms) download 47019 sequences with EC number 4.4 in fasta format download 47019 sequences with EC number 4.4 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.4) as tabstop separated file
4.99 Other lyases (136 organisms) download 41280 sequences with EC number 4.99 in fasta format download 41280 sequences with EC number 4.99 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 4.99) as tabstop separated file
5 Isomerases (2096 organisms) download 1415170 sequences with EC number 5 in fasta format download 1415170 sequences with EC number 5 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 5) as tabstop separated file
6 Ligases (1554 organisms) download 2087965 sequences with EC number 6 in fasta format download 2087965 sequences with EC number 6 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 6) as tabstop separated file
7 Translocases (1092 organisms) download 2299998 sequences with EC number 7 in fasta format download 2299998 sequences with EC number 7 as tabstop The data in BRENDA allow the calculation or simulation of metabolic pathways by extracting the information of substrate/product chains and the corresponding kinetic data of the preceding and following enzymes in the Boehringer and KEGG metabolism (with the risk of including ?pathways? with non-natural compounds). version Download 2822 PDB numbers (EC 7) as tabstop separated file