Q4J989 · HOSA_SULAC
- ProteinHomocitrate synthase
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids468 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Catalyzes the aldol-type condensation of 2-oxoglutarate with acetyl-CoA to yield homocitrate. Carries out the first step of the alpha-aminoadipate (AAA) lysine biosynthesis pathway. Does not display 2-isopropylmalate synthase and citramalate synthase activities since it cannot use 2-oxoisovalerate or pyruvate as substrate.
Catalytic activity
- 2-oxoglutarate + acetyl-CoA + H2O = (2R)-homocitrate + CoA + H+This reaction proceeds in the forward direction.
Cofactor
Mn2+ (UniProtKB | Rhea| CHEBI:29035 )
Activity regulation
Inhibited by lysine.
Pathway
Amino-acid biosynthesis; L-lysine biosynthesis via AAA pathway; L-alpha-aminoadipate from 2-oxoglutarate: step 1/5.
Features
Showing features for binding site, active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 19 | 2-oxoglutarate (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 20 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 83 | 2-oxoglutarate (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Binding site | 143 | 2-oxoglutarate (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 177 | 2-oxoglutarate (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 205 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Binding site | 207 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Active site | 299 | Proton acceptor | ||||
Sequence: H |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | homocitrate synthase activity | |
Molecular Function | metal ion binding | |
Biological Process | lysine biosynthetic process via aminoadipic acid |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Synthesis of homocitrate from acetyl-CoA and 2-oxoglutarate, the first (committed) step of lysine biosynthesis via the alpha-aminoadipate pathway. The enzyme is inhibited by lysine via its C-terminal RAM (Regulation of Amino acid Metabolism) domain.
Names & Taxonomy
Protein names
- Recommended nameHomocitrate synthase
- EC number
- Short namesHCS
Gene names
- Community suggested namesHomocitrate synthase; EC:2.3.3.14.
Organism names
- Strain
- Taxonomic lineageArchaea > Thermoproteota > Thermoprotei > Sulfolobales > Sulfolobaceae > Sulfolobus
Accessions
- Primary accessionQ4J989
Proteomes
Phenotypes & Variants
Disruption phenotype
Cells lacking this gene do not grow in MM without or even with lysine, but grow in MM with the simultaneous supplementation of lysine and arginine to the medium. Furthermore, the mutant strain does not grow on MM supplemented with lysine and glutamate, but grows with lysine and ornithine.
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000448052 | 1-468 | Homocitrate synthase | |||
Sequence: MLPKKKLHMKVGILDSTLREGEQTPGVVFTTDQRVEIAKALSDIGVQMIEAGHPAVSPDIYEGIRRIIKLKREGVIKSEIVAHSRAVKRDIEVGAEIEADRIAIFYGISDTHLKAKHHTTRDEALRSIAETVSYAKSHGVKVRFTAEDATRADYQYLLEVIKTVRDAGADRVSIADTVGVLYPSRTRELFKDLTSRFPDIEFDIHAHNDLGMAVANVLAAAEGGATIIHTTLNGLGERVGIAPLQVVAAALKYHFGIEVVDLKKLSEVASLVEKYSGIALPPNFPITGDYAFVHKAGVHVAGVLNDPKTYEFLPPETFGRSRDYVIDKYTGKHAVKDRFDRLGVKLTDSEIDQVLAKIKSNPNVRFYRDVDLLELAESVTGRILKPRPPENIMALISVKCDSNVYTTSVTRRIVLIEGVREVMEISGDYDILVKVEAKDSTELNQIIESIRAVKGVKSTLTSLILKKM |
Interaction
Protein-protein interaction databases
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 11-266 | Pyruvate carboxyltransferase | ||||
Sequence: VGILDSTLREGEQTPGVVFTTDQRVEIAKALSDIGVQMIEAGHPAVSPDIYEGIRRIIKLKREGVIKSEIVAHSRAVKRDIEVGAEIEADRIAIFYGISDTHLKAKHHTTRDEALRSIAETVSYAKSHGVKVRFTAEDATRADYQYLLEVIKTVRDAGADRVSIADTVGVLYPSRTRELFKDLTSRFPDIEFDIHAHNDLGMAVANVLAAAEGGATIIHTTLNGLGERVGIAPLQVVAAALKYHFGIEVVDLKKLS |
Domain
Contains an N-terminal catalytic domain fused with a RAM (Regulation of Amino acid Metabolism) domain at the C-terminus. The mutant enzyme lacking the RAM domain is insensitive to inhibition by lysine, indicating that the RAM domain is responsible for enzyme allosteric regulation.
Sequence similarities
Belongs to the alpha-IPM synthase/homocitrate synthase family. Homocitrate synthase LYS20/LYS21 subfamily.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length468
- Mass (Da)51,732
- Last updated2005-08-02 v1
- ChecksumB1C66520DDDCFBDE
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
CP000077 EMBL· GenBank· DDBJ | AAY80642.1 EMBL· GenBank· DDBJ | Genomic DNA |