Abstract
γ-Glutamyl transpeptidase (EC 2.3.2.2) activity is described in the coelenterate, Hydra attenuata, using the substrate γ-glutamyl-p-nitroanilide. The properties of the γ-glutamyl donor required for binding to the transpeptidase were investigated by measuring the ability of GSH analogs to inhibit the release of p-nitroaniline. Whereas no binding was observed when the γ-glutamyl moiety was altered, analogs with substitution in the Cys residue were capable of binding to the enzyme. A specificity for the Gly residue was indicated because analogs containing Leu or Tyr in place of Gly exhibited decreased binding capacities for the hydra transpeptidase. A comparison of these data with those obtained using the same analogs in the GSH induced feeding response bioassay shows that γ-glutamyl transpeptidase activity and the GSH receptor for the hydra feeding response have different specificities.
Original language | English (US) |
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Pages (from-to) | 180-186 |
Number of pages | 7 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 73 |
Issue number | 1 |
DOIs | |
State | Published - Nov 8 1976 |
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology