- Glutamate dehydrogenase
protein
Name= glutamate dehydrogenase 1
caption=
width=
HGNCid=4335
Symbol=GLUD1
AltSymbols=GLUD
EntrezGene=2746
OMIM=138130
RefSeq=NM_005271
UniProt=P00367
PDB=
ECnumber=1.4.1.3
Chromosome=10
Arm=q
Band=21.1
LocusSupplementaryData=-24.3protein
Name=glutamate dehydrogenase 2
caption=
width=
HGNCid=4336
Symbol=GLUD2
AltSymbols=GLUDP1
EntrezGene=2747
OMIM=300144
RefSeq=NM_012084
UniProt=P49448
PDB=
ECnumber=
Chromosome=X
Arm=q2
Band=5
LocusSupplementaryData=Glutamate dehydrogenase is an
enzyme , present inmitochondria ofeukaryotes , as are some of the other enzymes required forurea synthesis, that convertsglutamate to α-Ketoglutarate, and vice versa. The produced ammonia is, however, usually bled off to theurea cycle .The enzyme represents a key link between
catabolic andmetabolic pathways , and is therefore ubiquitous in eukaryotes.Cofactors
NAD+(or
NADP +) is acofactor for the glutamate dehydrogenase reaction, producing α-Ketoglutarate andammonium as a byproduct.Role in flow of nitrogen
Ammonia incorporation in animals occurs through the actions of glutamate dehydrogenase and
glutamine synthetase . Glutamate plays the central role inmammalian nitrogen flow, serving as both a nitrogen donor and nitrogen acceptor.Regulation of glutamate dehydrogenase
In Humans the activity of glutamate dehydrogenase is controlled through ADP-ribosylation, a covalent modification carried out by the gene
sirt4 . This regulation is relaxed in response tocaloric restriction and lowblood glucose . Under these circumstances glutamate dehydrogenase activity is raised to increase the amount of α-Ketoglutarate that is produced. The product α-Ketoglutarate can be used to provide energy by being used in thecitric acid cycle to ultimately produce ATP.The control of GDH through ADP-ribosylation is particularly important in
insulin producingβ cells . Beta cells secrete insulin in response to an increase in the ATP:ADP ratio, and as amino acids are broken down by GDH into α-ketoglutarate, this ratio rises and more insulin is secreted. SIRT4 is necessary to regulate the metabolism of amino acids as a method of controlling insulin secretion and to regulate bloodglucose levels.Regulation
Allosteric inhibitors:
*Adenosine triphosphate (ATP)
*Guanosine triphosphate (GTP)Activators:
*Adenosine diphosphate (ADP)
*Guanosine diphosphate (GDP)ee also
*
Anaplerotic reactions External links
*
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