| IED ID | IndEnz0002009840 |
| Enzyme Type ID | protease009840 |
| Protein Name |
Threonine dehydratase 2 biosynthetic, chloroplastic EC 4.3.1.17 EC 4.3.1.19 SlTD2 Threonine deaminase 2 Cleaved into: Processed threonine dehydratase 2 Processed TD2 pTD2 |
| Gene Name | TD2 TD |
| Organism | Solanum lycopersicum (Tomato) (Lycopersicon esculentum) |
| Taxonomic Lineage | cellular organisms Eukaryota Viridiplantae Streptophyta Streptophytina Embryophyta Tracheophyta Euphyllophyta Spermatophyta Magnoliopsida Mesangiospermae eudicotyledons Gunneridae Pentapetalae asterids lamiids Solanales Solanaceae Solanoideae Solaneae Solanum Solanum subgen. Lycopersicon Solanum lycopersicum (Tomato) (Lycopersicon esculentum) |
| Enzyme Sequence | MEFLCLAPTRSFSTNPKLTKSIPSDHTSTTSRIFTYQNMRGSTMRPLALPLKMSPIVSVPDITAPVENVPAILPKVVPGELIVNKPTGGDSDELFQYLVDILASPVYDVAIESPLELAEKLSDRLGVNFYIKREDKQRVFSFKLRGAYNMMSNLSREELDKGVITASAGNHAQGVALAGQRLNCVAKIVMPTTTPQIKIDAVRALGGDVVLYGKTFDEAQTHALELSEKDGLKYIPPFDDPGVIKGQGTIGTEINRQLKDIHAVFIPVGGGGLIAGVATFFKQIAPNTKIIGVEPYGAASMTLSLHEGHRVKLSNVDTFADGVAVALVGEYTFAKCQELIDGMVLVANDGISAAIKDVYDEGRNILETSGAVAIAGAAAYCEFYKIKNENIVAIASGANMDFSKLHKVTELAGLGSGKEALLATFMVEQQGSFKTFVGLVGSLNFTELTYRFTSERKNALILYRVNVDKESDLEKMIEDMKSSNMTTLNLSHNELVVDHLKHLVGGSANISDEIFGEFIVPEKAETLKTFLDAFSPRWNITLCRYRNQGDINASLLMGFQVPQAEMDEFKNQADKLGYPYELDNYNEAFNLVVSE |
| Enzyme Length | 595 |
| Uniprot Accession Number | P25306 |
| Absorption | |
| Active Site | |
| Activity Regulation | ACTIVITY REGULATION: Threonine dehydratase 2 biosynthetic, chloroplastic: Strongly inhibited by 1 mM isoleucine (PubMed:21436043). Processed threonine dehydratase 2: Not inhibited by isoleucine (PubMed:21436043, PubMed:17416643). {ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:21436043}. |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=L-threonine = 2-oxobutanoate + NH4(+); Xref=Rhea:RHEA:22108, ChEBI:CHEBI:16763, ChEBI:CHEBI:28938, ChEBI:CHEBI:57926; EC=4.3.1.19; Evidence={ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:2011578, ECO:0000269|PubMed:21436043}; CATALYTIC ACTIVITY: Reaction=L-serine = NH4(+) + pyruvate; Xref=Rhea:RHEA:19169, ChEBI:CHEBI:15361, ChEBI:CHEBI:28938, ChEBI:CHEBI:33384; EC=4.3.1.17; Evidence={ECO:0000269|PubMed:17416643}; |
| DNA Binding | |
| EC Number | 4.3.1.17; 4.3.1.19 |
| Enzyme Function | FUNCTION: [Threonine dehydratase 2 biosynthetic, chloroplastic]: Not required for normal growth and development of the plant (PubMed:21436043). {ECO:0000269|PubMed:21436043}.; FUNCTION: [Processed threonine dehydratase 2]: Involved in defense against lepidopteran, but not coleopteran herbivore insects (PubMed:21436043, PubMed:17416643). Acts in the insect gut to degrade threonine, which is an essential and limiting nutrient for the growth of lepidopteran larvae (Probable). Active against both L-threonine and L-serine (PubMed:17416643). {ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:21436043, ECO:0000305}. |
| Temperature Dependency | BIOPHYSICOCHEMICAL PROPERTIES: Temperature dependence: Threonine dehydratase 2 biosynthetic, chloroplastic: Optimum temperature is 60 degrees Celsius. Abnormally stable at elevated temperatures (PubMed:21436043). Processed threonine dehydratase 2: Active over a wide range of temperatures. Optimal enzyme activity against L-threonine is at 58 degrees Celsius (PubMed:17416643). {ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:21436043}; |
| PH Dependency | BIOPHYSICOCHEMICAL PROPERTIES: pH dependence: Threonine dehydratase 2 biosynthetic, chloroplastic: Active at alkaline pH (PubMed:21436043, PubMed:17416643). Processed threonine dehydratase 2: Optimum pH is 9. Has little or no activity at pH values below 6.0 (PubMed:17416643). {ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:21436043}; |
| Pathway | PATHWAY: Amino-acid biosynthesis; L-isoleucine biosynthesis; 2-oxobutanoate from L-threonine: step 1/1. |
| nucleotide Binding | |
| Features | Beta strand (12); Chain (2); Domain (2); Helix (20); Modified residue (1); Transit peptide (1) |
| Keywords | 3D-structure;Amino-acid biosynthesis;Branched-chain amino acid biosynthesis;Chloroplast;Direct protein sequencing;Isoleucine biosynthesis;Lyase;Plant defense;Plastid;Pyridoxal phosphate;Reference proteome;Repeat;Transit peptide |
| Interact With | Itself |
| Induction | INDUCTION: Expression is induced in response to methyl jasmonate (MeJA) and locally and systemically in response to mechanical wounding (PubMed:17416643). Parenchyma-specific induction of expression in flowers and leaves by MeJA. No induction of expression by MeJA in epidermal, vascular or sporogenous tissues (PubMed:7550377). Caterpillar (Helicoverpa zea) labial saliva induces expression in leaves damaged by herbivory (PubMed:23065106). {ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:23065106, ECO:0000269|PubMed:7550377}. |
| Subcellular Location | SUBCELLULAR LOCATION: Plastid, chloroplast {ECO:0000255}. |
| Modified Residue | MOD_RES 143; /note=N6-(pyridoxal phosphate)lysine; /evidence=ECO:0000250|UniProtKB:P04968 |
| Post Translational Modification | PTM: Proteolytically cleaved by a chymotrypsin-like digestive protease in the midgut of the lepidopteran insects to remove the C-terminal regulatory domain, which allows efficient metabolizing of threonine in the presence of high isoleucine levels in the gut. {ECO:0000269|PubMed:17416643, ECO:0000269|PubMed:21436043}. |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (1) |
| Cross Reference PDB | 3IAU; |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 64,937 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | RHEA:22108; RHEA:19169 |
| Cross Reference Brenda | 4.3.1.19; |