Enzymes
| UniProtKB help_outline | 468 proteins |
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- Name help_outline N2-(4-aminobutanoyl)-L-ornithine Identifier CHEBI:143160 Charge 1 Formula C9H20N3O3 InChIKeyhelp_outline PQOISWFOHLXORE-ZETCQYMHSA-O SMILEShelp_outline O=C([O-])[C@@H](NC(CCC[NH3+])=O)CCC[NH3+] 2D coordinates Mol file for the small molecule Search links Involved in 1 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H2O Identifier CHEBI:15377 (CAS: 7732-18-5) help_outline Charge 0 Formula H2O InChIKeyhelp_outline XLYOFNOQVPJJNP-UHFFFAOYSA-N SMILEShelp_outline [H]O[H] 2D coordinates Mol file for the small molecule Search links Involved in 6,648 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline 4-aminobutanoate Identifier CHEBI:59888 Charge 0 Formula C4H9NO2 InChIKeyhelp_outline BTCSSZJGUNDROE-UHFFFAOYSA-N SMILEShelp_outline [NH3+]CCCC([O-])=O 2D coordinates Mol file for the small molecule Search links Involved in 23 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline L-ornithine Identifier CHEBI:46911 Charge 1 Formula C5H13N2O2 InChIKeyhelp_outline AHLPHDHHMVZTML-BYPYZUCNSA-O SMILEShelp_outline [NH3+]CCC[C@H]([NH3+])C([O-])=O 2D coordinates Mol file for the small molecule Search links Involved in 58 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:59624 | RHEA:59625 | RHEA:59626 | RHEA:59627 | |
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| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
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| EC numbers help_outline |
Publications
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Metabolite proofreading in carnosine and homocarnosine synthesis: molecular identification of PM20D2 as beta-alanyl-lysine dipeptidase.
Veiga-da-Cunha M., Chevalier N., Stroobant V., Vertommen D., Van Schaftingen E.
Carnosine synthase is the ATP-dependent ligase responsible for carnosine (β-alanyl-histidine) and homocarnosine (γ-aminobutyryl-histidine) synthesis in skeletal muscle and brain, respectively. This enzyme uses, also at substantial rates, lysine, ornithine, and arginine instead of histidine, yet th ... >> More
Carnosine synthase is the ATP-dependent ligase responsible for carnosine (β-alanyl-histidine) and homocarnosine (γ-aminobutyryl-histidine) synthesis in skeletal muscle and brain, respectively. This enzyme uses, also at substantial rates, lysine, ornithine, and arginine instead of histidine, yet the resulting dipeptides are virtually absent from muscle or brain, suggesting that they are removed by a "metabolite repair" enzyme. Using a radiolabeled substrate, we found that rat skeletal muscle, heart, and brain contained a cytosolic β-alanyl-lysine dipeptidase activity. This enzyme, which has the characteristics of a metalloenzyme, was purified ≈ 200-fold from rat skeletal muscle. Mass spectrometry analysis of the fractions obtained at different purification stages indicated parallel enrichment of PM20D2, a peptidase of unknown function belonging to the metallopeptidase 20 family. Western blotting showed coelution of PM20D2 with β-alanyl-lysine dipeptidase activity. Recombinant mouse PM20D2 hydrolyzed β-alanyl-lysine, β-alanyl-ornithine, γ-aminobutyryl-lysine, and γ-aminobutyryl-ornithine as its best substrates. It also acted at lower rates on β-alanyl-arginine and γ-aminobutyryl-arginine but virtually not on carnosine or homocarnosine. Although acting preferentially on basic dipeptides derived from β-alanine or γ-aminobutyrate, PM20D2 also acted at lower rates on some "classic dipeptides" like α-alanyl-lysine and α-lysyl-lysine. The same activity profile was observed with human PM20D2, yet this enzyme was ∼ 100-200-fold less active on all substrates tested than the mouse enzyme. Cotransfection in HEK293T cells of mouse or human PM20D2 together with carnosine synthase prevented the accumulation of abnormal dipeptides (β-alanyl-lysine, β-alanyl-ornithine, γ-aminobutyryl-lysine), thus favoring the synthesis of carnosine and homocarnosine and confirming the metabolite repair role of PM20D2. << Less
J. Biol. Chem. 289:19726-19736(2014) [PubMed] [EuropePMC]
This publication is cited by 5 other entries.
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A peptidase that hydrolyzes Na-(gamma-aminobutyryl)lysine.
Kumon A., Matsuoka Y., Kakimoto Y., Nakajima T., Sano I.
Biochim Biophys Acta 200:466-474(1970) [PubMed] [EuropePMC]
This publication is cited by 5 other entries.