Gamma glutamyl transpeptidase

gamma-glutamyltransferase 1
Identifiers
Symbol	GGT1
Alt. symbols	GGT
Entrez	2678
HUGO	4250
OMIM	231950
RefSeq	NM_001032364
UniProt	P19440
Other data
EC number	2.3.2.2
Locus	Chr. 22 q11.1-11.2

gamma-glutamyltransferase 2
Identifiers
Symbol	GGT2
Alt. symbols	GGT
Entrez	2679
HUGO	4251
OMIM	137181
RefSeq	NM_002058
UniProt	P36268
Other data
EC number	2.3.2.2
Locus	Chr. 22 q11.1-11.2

gamma-glutamyltransferase 3
Identifiers
Symbol	GGT3
Entrez	2680
HUGO	4252
Other data
EC number	2.3.2.2
Locus	Chr. 22 [1]

Gamma glutamyl transferase (GGT or GGTP, or Gamma-GT) (EC 2.3.2.2) is primarily a liver enzyme.

Function

It is involved in the transfer of amino acids across the cellular membrane. It is also involved in glutathione metabolism by transfering the glutamyl moiety to a varitey of acceptor molecules including water, certain L-amino acids and peptides. Leaving the cystein product to preserve intracellular homeostasis of oxidative stress.

Location

GGT is found on the cell surface on all cells, with particularly high concentrations in the liver, bile ducts and kidney.

The enzyme is also present in other tissues, such as the epididymis.

Clinical significance

Its level in the blood may be tested for, as an elevated level may indicate an abnormality in the liver, though this can be caused by a number of conditions including:

• congestive heart failure
• cholestasis (congestion of the bile ducts)
• cirrhosis of the liver
• Restricted blood flow to the liver
• restricted venous outflow from liver like Budd-Chiari syndrome
• Necrosis of the liver
• Liver tumors
• hepatitis
• hepatotoxic drugs

Its levels are increased in chronic and acute alcohol abuse.

References

• MedlinePlus Encyclopedia 003458

External links

• gamma-Glutamyl+Transpeptidase at the US National Library of Medicine Medical Subject Headings (MeSH)