|
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| Enzyme Name | | Swiss-prot | KEGG |
|---|
| P22259 | O09460 | Q6W6X5 | Q5SLL5 | P51058 |
|---|
| Protein name | Phosphoenolpyruvate carboxykinase {ATP} | Phosphoenolpyruvate carboxykinase {ATP} |
| Phosphoenolpyruvate carboxykinase {ATP} | Phosphoenolpyruvate carboxykinase {ATP}, glycosomal | phosphoenolpyruvate carboxykinase (ATP)phosphopyruvate carboxylase (ATP)phosphoenolpyruvate carboxylasephosphoenolpyruvate carboxykinasephosphoenolpyruvate carboxykinasephosphopyruvate carboxykinase (adenosine triphosphate)PEP carboxylasePEP carboxykinasePEPCK (ATP)PEPKPEPCKphosphoenolpyruvic carboxylasephosphoenolpyruvic carboxykinasephosphoenolpyruvate carboxylase (ATP)phosphopyruvate carboxykinaseATP:oxaloacetate carboxy-lyase (transphosphorylating) |
|---|
| Synonyms | PEP carboxykinasePEPCKEC 4.1.1.49Phosphoenolpyruvate carboxylase | PEP carboxykinasePEPCKEC 4.1.1.49Phosphoenolpyruvate carboxylase | Phosphoenolpyruvate carboxykinaseEC 4.1.1.49 | PEP carboxykinasePEPCKEC 4.1.1.49Phosphoenolpyruvate carboxylase | EC 4.1.1.49 |
|---|
| KEGG pathways | | MAP code | Pathways |
|---|
| MAP00010 | Glycolysis / Gluconeogenesis | | MAP00020 | Citrate cycle (TCA cycle) | | MAP00620 | Pyruvate metabolism | | MAP00710 | Carbon fixation in photosynthetic organisms |
| Swiss-prot:Accession Number | P22259 | O09460 | Q6W6X5 | Q5SLL5 | P51058 |
|---|
| Entry name | PPCK_ECOLI | PPCK_ANASU | Q6W6X5_ACTSC | PCKA_THET8 | PPCK_TRYCR |
|---|
| Activity | ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). | ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). | ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). | ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). | ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). |
|---|
| Subunit | Monomer. |
|
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| Homodimer (By similarity). |
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| Subcellular location | Cytoplasm. | Cytoplasm (By similarity). | Cytoplasm (By Similarity). | Cytoplasm (By similarity). | Glycosome (By similarity). |
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| Cofactor |
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| Cofactors | Substrates | Products | intermediates |
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| KEGG-id | C00305 | C02148 | C00002 | C00036 | C00008 | C00074 | C00011 | I00001 |
|
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| Compound | Magnesium | Divalent metal | ATP | Oxaloacetate | ADP | Phosphoenolpyruvate | CO2 | Enolpyruvate | Transition-state of phosphoryl transfer |
|---|
| Type | divalent metal (Ca2+, Mg2+) | divalent metal (Ca2+, Mg2+) | amine group,nucleotide | carbohydrate,carboxyl group | amine group,nucleotide | carboxyl group,phosphate group/phosphate ion | others |
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| 1aq2A01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Intermediate-bound:PYR | Unbound |
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| 1aylA01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Intermediate-analogue:OXL | Unbound |
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| 1oenA01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1k3cA01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Intermediate-bound:PYR | Unbound |
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| 1k3dA01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1os1A01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Intermediate-bound:PYR | Unbound |
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| 1yvyA01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1yvyB01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1ylhA01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Intermediate-bound:PYR | Unbound |
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| 1wg9A01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1wg9B01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1ii2A01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1ii2B01 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1aq2A02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1aylA02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1oenA02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1k3cA02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1k3dA02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1os1A02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1yvyA02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1yvyB02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1ylhA02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1wg9A02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1wg9B02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1ii2A02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1ii2B02 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1aq2A03 |  | Bound:_MG | Bound:_MN | Bound:ATP | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1aylA03 |  | Bound:_MG | Unbound | Bound:ATP | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1oenA03 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1k3cA03 |  | Bound:_MG | Unbound | Unbound | Unbound | Bound:ADP | Unbound | Unbound | Unbound | Transition-state-analogue:ADP-AF3-PYR |
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| 1k3dA03 |  | Bound:_MG | Unbound | Unbound | Unbound | Bound:ADP | Unbound | Unbound | Unbound | Transition-state-analogue:ADP-AF3 |
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| 1os1A03 |  | Bound:_MG | Bound:_CA | Bound:ATP | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1yvyA03 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1yvyB03 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1ylhA03 |  | Unbound | Bound:_MN | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1wg9A03 |  | Unbound | Unbound | Bound:ATP | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1wg9B03 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
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| 1ii2A03 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| 1ii2B03 |  | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound | Unbound |
|---|
| References for Catalytic Mechanism | | References | Sections | No. of steps in catalysis |
|---|
| [2] | p.133-135 |
| | [3] | Fig.8, p.360-361 | 2 | | [5] | Scheme 2, p.8107-8108 | 2 | | [6] | Fig.3, p.992-994 | 3 | | [7] | p.6300-6301 |
| | [9] | p.3-5 |
| | [11] | p.87-89 |
| | [12] | p.1064-1066 |
| | [13] |
|
| | [14] |
|
| | [20] | Fig.9, p.4240-4241 | 3 | | [22] | Fig.4. p.275 | 2 | | [23] | Fig.7, p.1835 |
|
| references | | [1] |
|---|
| PubMed ID | 7756267 |
|---|
| Journal | Biochemistry |
|---|
| Year | 1995 |
|---|
| Volume | 34 |
|---|
| Pages | 6382-8 |
|---|
| Authors | Krautwurst H, Encinas MV, Marcus F, Latshaw SP, Kemp RG, Frey PA, Cardemil E |
|---|
| Title | Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase: revised amino acid sequence, site-directed mutagenesis, and microenvironment characteristics of cysteines 365 and 458. |
|---|
| [2] |
|---|
| Comments | X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS). |
|---|
| Medline ID | 96190956 |
|---|
| PubMed ID | 8609605 |
|---|
| Journal | J Mol Biol |
|---|
| Year | 1996 |
|---|
| Volume | 256 |
|---|
| Pages | 126-43 |
|---|
| Authors | Matte A, Goldie H, Sweet RM, Delbaere LT |
|---|
| Title | Crystal structure of Escherichia coli phosphoenolpyruvate carboxykinase: a new structural family with the P-loop nucleoside triphosphate hydrolase fold. |
|---|
| Related PDB | 1oen |
|---|
| Related Swiss-prot | P22259 |
|---|
| [3] |
|---|
| Comments | X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS). |
|---|
| Medline ID | 96185447 |
|---|
| PubMed ID | 8599762 |
|---|
| Journal | Nat Struct Biol |
|---|
| Year | 1996 |
|---|
| Volume | 3 |
|---|
| Pages | 355-63 |
|---|
| Authors | Tari LW, Matte A, Pugazhenthi U, Goldie H, Delbaere LT |
|---|
| Title | Snapshot of an enzyme reaction intermediate in the structure of the ATP-Mg2+-oxalate ternary complex of Escherichia coli PEP carboxykinase. |
|---|
| Related PDB | 1ayl |
|---|
| Related Swiss-prot | P22259 |
|---|
| [4] |
|---|
| PubMed ID | 9048893 |
|---|
| Journal | Biochim Biophys Acta |
|---|
| Year | 1997 |
|---|
| Volume | 1337 |
|---|
| Pages | 166-74 |
|---|
| Authors | Bazaes S, Montecinos L, Krautwurst H, Goldie H, Cardemil E, Jabalquinto AM |
|---|
| Title | Identification of reactive conserved histidines in phosphoenolpyruvate carboxykinases from Escherichia coli and Saccharomyces cerevisiae. |
|---|
| [5] |
|---|
| PubMed ID | 9139042 |
|---|
| Journal | J Biol Chem |
|---|
| Year | 1997 |
|---|
| Volume | 272 |
|---|
| Pages | 8105-8 |
|---|
| Authors | Matte A, Tari LW, Goldie H, Delbaere LT |
|---|
| Title | Structure and mechanism of phosphoenolpyruvate carboxykinase. |
|---|
| [6] |
|---|
| Comments | X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS). |
|---|
| Medline ID | 98069645 |
|---|
| PubMed ID | 9406547 |
|---|
| Journal | Nat Struct Biol |
|---|
| Year | 1997 |
|---|
| Volume | 4 |
|---|
| Pages | 990-4 |
|---|
| Authors | Tari LW, Matte A, Goldie H, Delbaere LT |
|---|
| Title | Mg(2+)-Mn2+ clusters in enzyme-catalyzed phosphoryl-transfer reactions. |
|---|
| Related PDB | 1aq2 |
|---|
| Related Swiss-prot | P22259 |
|---|
| [7] |
|---|
| PubMed ID | 9572844 |
|---|
| Journal | Biochemistry |
|---|
| Year | 1998 |
|---|
| Volume | 37 |
|---|
| Pages | 6295-302 |
|---|
| Authors | Krautwurst H, Bazaes S, Gonzalez FD, Jabalquinto AM, Frey PA, Cardemil E |
|---|
| Title | The strongly conserved lysine 256 of Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase is essential for phosphoryl transfer. |
|---|
| [8] |
|---|
| PubMed ID | 10609641 |
|---|
| Journal | J Protein Chem |
|---|
| Year | 1999 |
|---|
| Volume | 18 |
|---|
| Pages | 659-64 |
|---|
| Authors | Jabalquinto AM, Laivenieks M, Zeikus JG, Cardemil E |
|---|
| Title | Characterization of the oxaloacetate decarboxylase and pyruvate kinase-like activities of Saccharomyces cerevisiae and Anaerobiospirillum succiniciproducens phosphoenolpyruvate carboxykinases. |
|---|
| [9] |
|---|
| PubMed ID | 11277994 |
|---|
| Journal | FEBS Lett |
|---|
| Year | 2001 |
|---|
| Volume | 493 |
|---|
| Pages | 1-5 |
|---|
| Authors | Llanos L, Briones R, Yevenes A, Gonzalez-Nilo FD, Frey PA, Cardemil E |
|---|
| Title | Mutation Arg336 to Lys in Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase originates an enzyme with increased oxaloacetate decarboxylase activity. |
|---|
| [10] |
|---|
| PubMed ID | 11445561 |
|---|
| Journal | J Biol Chem |
|---|
| Year | 2001 |
|---|
| Volume | 276 |
|---|
| Pages | 33705-10 |
|---|
| Authors | Yeagley D, Guo S, Unterman T, Quinn PG |
|---|
| Title | Gene- and activation-specific mechanisms for insulin inhibition of basal and glucocorticoid-induced insulin-like growth factor binding protein-1 and phosphoenolpyruvate carboxykinase transcription. Roles of forkhead and insulin response sequences. |
|---|
| [11] |
|---|
| PubMed ID | 11724534 |
|---|
| Journal | J Mol Biol |
|---|
| Year | 2001 |
|---|
| Volume | 314 |
|---|
| Pages | 83-92 |
|---|
| Authors | Sudom AM, Prasad L, Goldie H, Delbaere LT |
|---|
| Title | The phosphoryl-transfer mechanism of Escherichia coli phosphoenolpyruvate carboxykinase from the use of AlF(3). |
|---|
| Related PDB | 1k3c,1k3d |
|---|
| [12] |
|---|
| PubMed ID | 11700062 |
|---|
| Journal | J Mol Biol |
|---|
| Year | 2001 |
|---|
| Volume | 313 |
|---|
| Pages | 1059-72 |
|---|
| Authors | Trapani S, Linss J, Goldenberg S, Fischer H, Craievich AF, Oliva G |
|---|
| Title | Crystal structure of the dimeric phosphoenolpyruvate carboxykinase (PEPCK) from Trypanosoma cruzi at 2 A resolution. |
|---|
| Related PDB | 1ii2 |
|---|
| [13] |
|---|
| PubMed ID | 12379119 |
|---|
| Journal | Biochemistry |
|---|
| Year | 2002 |
|---|
| Volume | 41 |
|---|
| Pages | 12763-70 |
|---|
| Authors | Krautwurst H, Roschzttardtz H, Bazaes S, Gonzalez-Nilo FD, Nowak T, Cardemil E |
|---|
| Title | Lysine 213 and histidine 233 participate in Mn(II) binding and catalysis in Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase. |
|---|
| [14] |
|---|
| PubMed ID | 12479406 |
|---|
| Journal | Biochim Biophys Acta |
|---|
| Year | 2002 |
|---|
| Volume | 1599 |
|---|
| Pages | 65-71 |
|---|
| Authors | Gonzalez-Nilo FD, Krautwurst H, Yevenes A, Cardemil E, Cachau R |
|---|
| Title | Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase: theoretical and experimental study of the effect of glutamic acid 284 on the protonation state of lysine 213. |
|---|
| [15] |
|---|
| PubMed ID | 12062398 |
|---|
| Journal | FEBS Lett |
|---|
| Year | 2002 |
|---|
| Volume | 517 |
|---|
| Pages | 1-6 |
|---|
| Authors | Russell RB, Marquez JA, Hengstenberg W, Scheffzek K |
|---|
| Title | Evolutionary relationship between the bacterial HPr kinase and the ubiquitous PEP-carboxykinase: expanding the P-loop nucleotidyl transferase superfamily. |
|---|
| [16] |
|---|
| PubMed ID | 11943595 |
|---|
| Journal | Int J Biochem Cell Biol |
|---|
| Year | 2002 |
|---|
| Volume | 34 |
|---|
| Pages | 645-56 |
|---|
| Authors | Encinas MV, Gonzalez-Nilo FD, Andreu JM, Alfonso C, Cardemil E |
|---|
| Title | Urea-induced unfolding studies of free- and ligand-bound tetrameric ATP-dependent Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase. Influence of quaternary structure on protein conformational stability. |
|---|
| [17] |
|---|
| PubMed ID | 11851336 |
|---|
| Journal | J Mol Biol |
|---|
| Year | 2002 |
|---|
| Volume | 316 |
|---|
| Pages | 257-64 |
|---|
| Authors | Dunten P, Belunis C, Crowther R, Hollfelder K, Kammlott U, Levin W, Michel H, Ramsey GB, Swain A, Weber D, Wertheimer SJ |
|---|
| Title | Crystal structure of human cytosolic phosphoenolpyruvate carboxykinase reveals a new GTP-binding site. |
|---|
| [18] |
|---|
| PubMed ID | 12523647 |
|---|
| Journal | J Protein Chem |
|---|
| Year | 2002 |
|---|
| Volume | 21 |
|---|
| Pages | 443-5 |
|---|
| Authors | Jabalquinto AM, Laivenieks M, Cabezas M, Zeikus JG, Cardemil E |
|---|
| Title | The effect of active site mutations in the oxaloacetate decarboxylase and pyruvate kinase-like activities of Anaerobiospirillum succiniciproducens phosphoenolpyruvate carboxykinase. |
|---|
| [19] |
|---|
| PubMed ID | 12359875 |
|---|
| Journal | Proc Natl Acad Sci U S A |
|---|
| Year | 2002 |
|---|
| Volume | 99 |
|---|
| Pages | 13437-41 |
|---|
| Authors | Fieulaine S, Morera S, Poncet S, Mijakovic I, Galinier A, Janin J, Deutscher J, Nessler S |
|---|
| Title | X-ray structure of a bifunctional protein kinase in complex with its protein substrate HPr. |
|---|
| [20] |
|---|
| PubMed ID | 12837799 |
|---|
| Journal | J Bacteriol |
|---|
| Year | 2003 |
|---|
| Volume | 185 |
|---|
| Pages | 4233-42 |
|---|
| Authors | Sudom A, Walters R, Pastushok L, Goldie D, Prasad L, Delbaere LT, Goldie H |
|---|
| Title | Mechanisms of activation of phosphoenolpyruvate carboxykinase from Escherichia coli by Ca2+ and of desensitization by trypsin. |
|---|
| Related PDB | 1os1 |
|---|
| [21] |
|---|
| PubMed ID | 13678294 |
|---|
| Journal | J Protein Chem |
|---|
| Year | 2003 |
|---|
| Volume | 22 |
|---|
| Pages | 311-5 |
|---|
| Authors | Ravanal MC, Goldie H, Cardemil E |
|---|
| Title | Thermal stability of phosphoenolpyruvate carboxykinases from Escherichia coli, Trypanosoma brucei, and Saccharomyces cerevisiae. |
|---|
| [22] |
|---|
| PubMed ID | 15023367 |
|---|
| Journal | Biochim Biophys Acta |
|---|
| Year | 2004 |
|---|
| Volume | 1697 |
|---|
| Pages | 271-8 |
|---|
| Authors | Delbaere LT, Sudom AM, Prasad L, Leduc Y, Goldie H |
|---|
| Title | Structure/function studies of phosphoryl transfer by phosphoenolpyruvate carboxykinase. |
|---|
| [23] |
|---|
| PubMed ID | 15890557 |
|---|
| Journal | Int J Biochem Cell Biol |
|---|
| Year | 2005 |
|---|
| Volume | 37 |
|---|
| Pages | 1829-37 |
|---|
| Authors | Cotelesage JJ, Prasad L, Zeikus JG, Laivenieks M, Delbaere LT |
|---|
| Title | Crystal structure of Anaerobiospirillum succiniciproducens PEP carboxykinase reveals an important active site loop. |
|---|
| Related PDB | 1yvy |
|---|
| [24] |
|---|
| PubMed ID | 15983413 |
|---|
| Journal | Acta Crystallogr D Biol Crystallogr |
|---|
| Year | 2005 |
|---|
| Volume | 61 |
|---|
| Pages | 903-12 |
|---|
| Authors | Leduc YA, Prasad L, Laivenieks M, Zeikus JG, Delbaere LT |
|---|
| Title | Structure of PEP carboxykinase from the succinate-producing Actinobacillus succinogenes: a new conserved active-site motif. |
|---|
| Related PDB | 1ylh |
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| comments | There are several types of Phosphoenolpyruvate carboxykinases; E.C. 4.1.1.49 (ATP-dependent and found in plants and microorganisms), E.C. 4.1.1.32 (GTP-dependent and found in higher organism), and E.C. 4.1.1.38 (diphosphate-dependent). This enzyme belongs to the ATP-dependent one. Interestingly, lysine residue is coordinated to the divalent metal ion, as it is deprotonated (see [13] & [14]). This enzyme binds a magnesium ion, which is bound to beta- and gamma-phosphate groups of ATP, and a second divalent metal, which is bound between ATP and another substrate. Both the metal ions are involved in catalysis. According to the literature [3], [5], [6], [7], [11], [20] & [22], this enzyme catalyzes two successive reactions, (A) decarboxylation and (B) phophoryl transfer as follows; (A) Decarboxylation; Eliminative double-bond formation. (A1) A divalent metal ion such as manganese and calcium facilitates the bond cleavage between the mehtylene carbon and carboxylate (probably through a water). On the other hand, the leaving carboxylate group is stabilized by Tyr207 (of 2aq2). (A2) Bond cleavage occurs via E1-like mechanism, forming an enolpyruvate intermediate. (B) Transfer of phosphoryl group from ATP to enolepyruvate intermediate (see [6], [20] & [22]). (B1) In the initial stage, a divalent metal is bound to gamma-phosphate and two water, along with Asp269/His232/Lys213 (in the case of manganese). The oxygen of the enolate intermediate is away from the divalent metal ion (in the case of manganese). (B2) The magnesium ion, bound to the beta- and gamma-phosphate oxygens, stabilizes the negative charge developed on the leaving phosphate and transferred phosphate together with the sidechain of Lys254 and the mainchain amide of Gly251, and polarizes the P-O bond in the gamma-phosphoryl group by making the gamma-phosphate more electrophilic. (B3) (In the case of manganese ion as the second metal ion, the enol oxygen displaces a water molecule bound to the divalent metal, in order to be in line with the gamma-phosphate group.) (B4) The second metal ion neutralizes the electrostatic repulsion between the enol oxygen and phosphate group, along with Arg333. (B5) The enol oxygen makes a nucleophilic attack on the gamma-phosphorus atom. The transfer reaction occurs via SN-2-like mechanism.
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| created | updated |
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| 2004-07-07 | 2009-04-03 |
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