DB code: T00084

RLCP classification 5.115.3380000.410 : Elimination
3.103.90020.1140 : Transfer
CATH domain 3.40.449.10 : Phosphoenolpyruvate Carboxykinase; domain 1 Catalytic domain
2.170.8.10 : Phosphoenolpyruvate Carboxykinase; domain 2 Catalytic domain
3.90.228.20 : Phosphoenolpyruvate Carboxykinase; domain 3 Catalytic domain
E.C. 4.1.1.49
CSA 1aq2
M-CSA 1aq2
MACiE M0051

CATH domain Related DB codes (homologues)

Uniprot Enzyme Name
UniprotKB Protein name Synonyms RefSeq Pfam
P22259 Phosphoenolpyruvate carboxykinase {ATP}
PEP carboxykinase
PEPCK
EC 4.1.1.49
Phosphoenolpyruvate carboxylase
NP_417862.1 (Protein)
NC_000913.2 (DNA/RNA sequence)
YP_492029.1 (Protein)
NC_007779.1 (DNA/RNA sequence)
PF01293 (PEPCK_ATP)
[Graphical View]
O09460 Phosphoenolpyruvate carboxykinase {ATP}
PEP carboxykinase
PEPCK
EC 4.1.1.49
Phosphoenolpyruvate carboxylase
PF01293 (PEPCK_ATP)
[Graphical View]
Q6W6X5 Phosphoenolpyruvate carboxykinase {ATP}
PEP carboxykinase
PEPCK
EC 4.1.1.49
Phosphoenolpyruvate carboxylase
PF01293 (PEPCK_ATP)
[Graphical View]
Q5SLL5 Phosphoenolpyruvate carboxykinase {ATP}
PEP carboxykinase
PEPCK
EC 4.1.1.49
Phosphoenolpyruvate carboxylase
YP_143544.1 (Protein)
NC_006461.1 (DNA/RNA sequence)
PF01293 (PEPCK_ATP)
[Graphical View]
P51058 Phosphoenolpyruvate carboxykinase {ATP}, glycosomal
EC 4.1.1.49
PF01293 (PEPCK_ATP)
[Graphical View]

KEGG enzyme name
phosphoenolpyruvate carboxykinase (ATP)
phosphopyruvate carboxylase (ATP)
phosphoenolpyruvate carboxylase
phosphoenolpyruvate carboxykinase
phosphoenolpyruvate carboxykinase
phosphopyruvate carboxykinase (adenosine triphosphate)
PEP carboxylase
PEP carboxykinase
PEPCK (ATP)
PEPK
PEPCK
phosphoenolpyruvic carboxylase
phosphoenolpyruvic carboxykinase
phosphoenolpyruvate carboxylase (ATP)
phosphopyruvate carboxykinase
ATP:oxaloacetate carboxy-lyase (transphosphorylating)

UniprotKB: Accession Number Entry name Activity Subunit Subcellular location Cofactor
P22259 PPCK_ECOLI ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). Monomer. Cytoplasm.
O09460 PPCK_ANASU ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). Cytoplasm (By similarity).
Q6W6X5 Q6W6X5_ACTSC ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). Cytoplasm (By Similarity).
Q5SLL5 PCKA_THET8 ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). Cytoplasm (By similarity).
P51058 PPCK_TRYCR ATP + oxaloacetate = ADP + phosphoenolpyruvate + CO(2). Homodimer (By similarity). Glycosome (By similarity).

KEGG Pathways
Map code Pathways E.C.
MAP00010 Glycolysis / Gluconeogenesis
MAP00020 Citrate cycle (TCA cycle)
MAP00620 Pyruvate metabolism
MAP00710 Carbon fixation in photosynthetic organisms

Compound table
Cofactors Substrates Products Intermediates
KEGG-id C00305 C02148 C00002 C00036 C00008 C00074 C00011 I00001
E.C.
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
ChEBI 18420
 18420
 		15422
 15422
 		30744
 30744
 		16761
 16761
 		44897
 44897
 		16526
 16526
PubChem 888
 888
 		5957
 5957
 		970
 970
 		6022
 6022
 		1005
 58114173
 59658623
 1005
 58114173
 59658623
 		280
 280
1aq2A01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Intermediate-bound:PYR Unbound
1aylA01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Intermediate-analogue:OXL Unbound
1oenA01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1k3cA01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Intermediate-bound:PYR Unbound
1k3dA01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1os1A01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Intermediate-bound:PYR Unbound
1yvyA01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1yvyB01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ylhA01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Intermediate-bound:PYR Unbound
1wg9A01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1wg9B01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ii2A01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ii2B01 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1aq2A02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1aylA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1oenA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1k3cA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1k3dA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1os1A02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1yvyA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1yvyB02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ylhA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1wg9A02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1wg9B02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ii2A02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ii2B02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1aq2A03 Bound:_MG Bound:_MN Bound:ATP Unbound Unbound Unbound Unbound Unbound Unbound
1aylA03 Bound:_MG Unbound Bound:ATP Unbound Unbound Unbound Unbound Unbound Unbound
1oenA03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1k3cA03 Bound:_MG Unbound Unbound Unbound Bound:ADP Unbound Unbound Unbound Transition-state-analogue:ADP-AF3-PYR
1k3dA03 Bound:_MG Unbound Unbound Unbound Bound:ADP Unbound Unbound Unbound Transition-state-analogue:ADP-AF3
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
1ii2A03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1ii2B03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound

Reference for Active-site residues
resource references E.C.
literature [3], [4], [7], [13], [20] & [22]

Active-site residues
PDB Catalytic residues Cofactor-binding residues Modified residues Main-chain involved in catalysis Comment
1aq2A01 TYR 207 LYS 213(2nd metal binding)
1aylA01 TYR 207 LYS 213(2nd metal binding)
1oenA01 TYR 207 LYS 213(2nd metal binding)
1k3cA01 TYR 207 LYS 213(2nd metal binding)
1k3dA01 TYR 207 LYS 213(2nd metal binding)
1os1A01 TYR 207 LYS 213(2nd metal binding)
1yvyA01 TYR 200 LYS 206(2nd metal binding)
1yvyB01 TYR 1200 LYS 1206(2nd metal binding)
1ylhA01 TYR 207 LYS 213(2nd metal binding)
1wg9A01 TYR 191 LYS 197(2nd metal binding)
1wg9B01 TYR 191 LYS 197(2nd metal binding)
1ii2A01 TYR 180 LYS 186(2nd metal binding)
1ii2B01 TYR 180 LYS 186(2nd metal binding)
1aq2A02 ARG 333
1aylA02 ARG 333
1oenA02 ARG 333
1k3cA02 ARG 333
1k3dA02 ARG 333
1os1A02 ARG 333
1yvyA02 ARG 327
1yvyB02 ARG 1327
1ylhA02 ARG 333
1wg9A02 ARG 319
1wg9B02 ARG 319
1ii2A02 ARG 307
1ii2B02 ARG 307
1aq2A03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1aylA03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1oenA03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1k3cA03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1k3dA03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1os1A03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1yvyA03 LYS 248 HIS 225;ASP 263(2nd metal binding);THR 249(Magnesium binding) GLY 245
1yvyB03 LYS 1248 HIS 1225;ASP 1263(2nd metal binding);THR 1249(Magnesium binding) GLY 1245
1ylhA03 LYS 254 HIS 232;ASP 269(2nd metal binding);THR 255(Magnesium binding) GLY 251
1wg9A03 LYS 238 HIS 216;ASP 253(2nd metal binding);THR 239(Magnesium binding) GLY 235
1wg9B03 LYS 238 HIS 216;ASP 253(2nd metal binding);THR 239(Magnesium binding) GLY 235
1ii2A03 LYS 227 HIS 205;ASP 242(2nd metal binding);THR 228(Magnesium binding) GLY 224
1ii2B03 LYS 227 HIS 205;ASP 242(2nd metal binding);THR 228(Magnesium binding) GLY 224

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]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[2]
Resource
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 UniProtKB P22259
[3]
Resource
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 UniProtKB P22259
[4]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[5]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[6]
Resource
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 UniProtKB P22259
[7]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[8]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[9]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[10]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[11]
Resource
Comments
Medline ID
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
Related UniProtKB
[12]
Resource
Comments
Medline ID
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
Related UniProtKB
[13]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[14]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[15]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[16]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[17]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[18]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[19]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[20]
Resource
Comments
Medline ID
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
Related UniProtKB
[21]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[22]
Resource
Comments
Medline ID
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.
Related PDB
Related UniProtKB
[23]
Resource
Comments
Medline ID
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
Related UniProtKB
[24]
Resource
Comments
Medline ID
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
Related UniProtKB

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.

Created Updated
2004-07-07 2009-04-03