Rat Gamma-glutamyltransferase 5,GGT5 ELI

Cleaves the gamma-glutamyl peptide bond of glutathione and glutathione-S-conjugate.

Converts leukotriene C4 (LTC4), a glutathione-S-conjugate, to leukotriene D4 (LTD4).

Does not cleave gamma-glutamyl compounds such as gamma-glutamyl leucine.

May also catalyze a transpeptidation reaction in addition to the hydrolysis reaction, transferring the gamma-glutamyl moiety to an acceptor amino acid to form a new gamma-glutamyl compound.

Acts as a negative regulator of geranylgeranyl glutathione bioactivity by cleaving off its gamma-glutamyl group, playing a role in adaptive immune responses.

{ECO:0000250|UniProtKB:P36269}.