KEGG   ENZYME: 6.3.4.16Help
Entry
EC 6.3.4.16                 Enzyme                                 

Name
carbamoyl-phosphate synthase (ammonia);
carbon-dioxide---ammonia ligase;
carbamoylphosphate synthase;
carbamylphosphate synthetase;
carbamoylphosphate synthase (ammonia);
carbamoylphosphate synthetase;
carbamylphosphate synthetase I;
CPSI (gene name);
carbon-dioxide:ammonia ligase (ADP-forming, carbamate-phosphorylating)
Class
Ligases;
Forming carbon-nitrogen bonds;
Other carbon-nitrogen ligases
BRITE hierarchy
Sysname
hydrogencarbonate:ammonia ligase (ADP-forming, carbamate-phosphorylating)
Reaction(IUBMB)
2 ATP + NH3 + hydrogencarbonate = 2 ADP + phosphate + carbamoyl phosphate (overall reaction) [RN:R00149];
(1a) ATP + hydrogencarbonate = ADP + carboxyphosphate;
(1b) NH3 + carboxyphosphate = carbamate + phosphate;
(1c) ATP + carbamate = ADP + carbamoyl phosphate
Reaction(KEGG)
Substrate
ATP [CPD:C00002];
NH3 [CPD:C00014];
hydrogencarbonate;
carboxyphosphate [CPD:C20969];
carbamate [CPD:C01563]
Product
ADP [CPD:C00008];
phosphate [CPD:C00009];
carbamoyl phosphate [CPD:C00169];
carboxyphosphate [CPD:C20969];
carbamate [CPD:C01563]
Comment
The enzyme catalyses the first committed step in the urea cycle. The reaction proceeds via three separate chemical reactions: phosphorylation of hydrogencarbonate to carboxyphosphate; a nucleophilic attack of ammonia on carboxyphosphate yielding carbamate; and the phosphorylation of carbamate forming carbamoyl phosphate. Two moles of ATP are utilized for the synthesis of one molecule of carbamyl phosphate, making the reaction essentially irreversible. The enzyme requires the allosteric activator N-acetyl-L-glutamate. cf. EC 6.3.5.5, carbamoyl-phosphate synthase (glutamine-hydrolysing).
History
EC 6.3.4.16 created 1965 as EC 2.7.2.5, transferred 1978 to EC 6.3.4.16
Pathway
Arginine biosynthesis
Alanine, aspartate and glutamate metabolism
Nitrogen metabolism
Metabolic pathways
Microbial metabolism in diverse environments
Orthology
K01948  
carbamoyl-phosphate synthase (ammonia)
Genes
HSA: 
1373(CPS1)
PTR: 
738670(CPS1)
PPS: 
100984596(CPS1)
GGO: 
101130709(CPS1)
PON: 
100442727(CPS1)
NLE: 
100596216(CPS1)
MCC: 
711806(CPS1)
MCF: 
102139369(CPS1)
RRO: 
104655495(CPS1)
CJC: 
100402602(CPS1)
MMU: 
227231(Cps1)
RNO: 
497840(Cps1)
CGE: 
100760467(Cps1)
NGI: 
103744467(Cps1)
HGL: 
101696508(Cps1)
OCU: 
100303765(CPS1)
TUP: 
102491899(CPS1)
CFA: 
488506(CPS1)
AML: 
100466842(CPS1)
UMR: 
103659822(CPS1)
FCA: 
101099824(CPS1)
PTG: 
102968283(CPS1)
BTA: 
510506(CPS1)
BOM: 
102267831(CPS1)
PHD: 
102342950(CPS1)
CHX: 
102179612(CPS1)
OAS: 
101107584(CPS1)
SSC: 
100157716(CPS1)
CFR: 
BACU: 
103003987(CPS1)
LVE: 
103079188(CPS1)
ECB: 
100050116(CPS1)
MYB: 
102262103(CPS1)
MYD: 
102756563(CPS1)
PALE: 
102895317(CPS1)
MDO: 
100015090(CPS1)
SHR: 
100929825(CPS1)
OAA: 
100077228(CPS1)
GGA: 
428994(CPS1)
MGP: 
100539661(CPS1)
APLA: 
101797791(CPS1)
TGU: 
100221389(CPS1)
GFR: 
102044867(CPS1)
FAB: 
101816308(CPS1)
PHI: 
102105821(CPS1)
CCW: 
104694540(CPS1)
FPG: 
101910440(CPS1)
FCH: 
102046837(CPS1)
CLV: 
102091543(CPS1)
ASN: 
102386005(CPS1)
AMJ: 
106736782(CPS1)
PSS: 
102462440(CPS1)
CMY: 
102943091(CPS1)
ACS: 
100562333(cps1)
PBI: 
103061484(CPS1)
XLA: 
733340(cps1)
XTR: 
100158506(cps1)
DRE: 
555623(cps1)
TRU: 
101074466(cps1)
MZE: 
101479159(cps1)
OLA: 
101164854(cps1)
XMA: 
102232024(cps1)
LCM: 
102363877(CPS1)
CMK: 
103182939(cps1)
BFO: 
SPU: 
SKO: 
LGI: 
OBI: 
PTI: 
TPS: 
AAF: 
PIF: 
PSOJ: 
SPAR: 
 » show all
Taxonomy
Reference
1  [PMID:14213379]
  Authors
FAHIEN LA, COHEN PP.
  Title
A KINETIC STUDY OF CARBAMYL PHOSPHATE SYNTHETASE.
  Journal
J. Biol. Chem. 239 (1964) 1925-34.
Reference
2  [PMID:13790558]
  Authors
JONES ME, SPECTOR L.
  Title
The pathway of carbonate in the biosynthesis of carbamyl phosphate.
  Journal
J. Biol. Chem. 235 (1960) 2897-901.
Reference
3  [PMID:13563449]
  Authors
METZENBERG RL, MARSHALL M, COHEN PP.
  Title
Purification of carbamyl phosphate synthetase from frog liver.
  Journal
J. Biol. Chem. 233 (1958) 102-5.
Reference
4  [PMID:26151989]
  Authors
Marshall M, Metzenberg RL, Cohen PP
  Title
Physical and Kinetic Properties of Carbamyl Phosphate Synthetase from Frog Liver.
  Journal
J. Biol. Chem. 236 (1961) 2229-37.
Reference
5  [PMID:6249820]
  Authors
Pierson DL, Brien JM
  Title
Human carbamylphosphate synthetase I. Stabilization, purification, and partial characterization of the enzyme from human liver.
  Journal
J. Biol. Chem. 255 (1980) 7891-5.
Reference
6  [PMID:19754428]
  Authors
Pekkala S, Martinez AI, Barcelona B, Gallego J, Bendala E, Yefimenko I, Rubio V, Cervera J
  Title
Structural insight on the control of urea synthesis: identification of the binding site for N-acetyl-L-glutamate, the essential allosteric activator of mitochondrial carbamoyl phosphate synthetase.
  Journal
Biochem. J. 424 (2009) 211-20.
Other DBs
ExplorEnz - The Enzyme Database: 
IUBMB Enzyme Nomenclature: 
ExPASy - ENZYME nomenclature database: 
BRENDA, the Enzyme Database: 
CAS: 
9026-23-7

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