Farnesyl protein transferase (FPTase) catalyzes the covalent attachment of a farnesyl (C15) group from farnesyl pyrophosphate (FPP) to a specific cysteine residue of Ras and several other proteins. In this report, photo-active farnesyl and geranylgeranyl pyrophosphate analogs 2-diazo-3,3,3-trifluoropropionyloxy-geranyl pyrophosphate (DATFP-GPP) and 2-diazo-3,3,3-trifluoropropionyloxy-farnesyl pyrophosphate (DATFP-FPP) were used to study the active site of Saccharomyces cerevisiae FPTase. Both analogs are substrates for the enzyme, and upon irradiation, DATFP-GPP inhibits FPTase activity in a time-dependent manner. Photoinactivation by DATFP-GPP is prevented by the presence of the natural substrate FPP. Photolysis of radiolabeled DATFP-GPP results in preferential labeling of the β subunit of FPTase, suggesting that this subunit is involved in recognition of FPP. Of particular importance, DATFP-GPP and DATFP-FPP were used to enzymatically transfer the photo-active isoprenoid moieties to peptides and to Ras; such molecules should be useful for identifying cellular components which specifically recognize farnesylated Ras and other prenylated proteins.
|Original language||English (US)|
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Jun 18 1997|
Bibliographical noteFunding Information:
1This research was supported by the American Cancer Society (Grants BE-222 and IN-13-33-47). 2To whom correspondence should be addressed.