Structural and biochemical studies of protein prenyltransferases using a photoactivatible isoprenoid diphosphate analog containing a stable phosphonate linkage

ORGN 396

Amanda J DeGraw, degraw@chem.umn.edu1, Zongbao Zhao2, Huma A Taban3, Wenshuang Xie4, David K. Shintani, shintani@unr.edu5, Colleen McMahan4, and Mark D. Distefano, diste001@umn.edu6. (1) Department of Chemistry, Univeristy of Minnesota, 207 Pleasant St SE, Minneapolis, MN 55455, (2) Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, (3) Department of Biochemistry, Univeristy of Nevada, Reno, NV 89557, (4) Agricultural Research Service, United States Department of Agriculture, Albany, CA 94710, (5) Department of Biochemistry, University of Nevada, MS200, Fleischmann Agriculture Building Rm 311C, Reno, NV 89557, (6) Departments of Chemistry and Medicinal Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455
Photoactivatible isoprenoid diphosphate analogues have proven useful for studying isoprenoid utilizing enzymes such as the isoprenoid synthases and prenyltransferases. While these analogues have shown to be excellent structural analogues, they suffer from instability given the acid labile nature of the allylic diphosphate linkage. Stability is needed when the goals include isolation of cross-linked species, tryptic digestion, and subsequent peptide sequencing. Here we report on the synthesis of a farnesyl diphosphate (FPP) analogue containing a stable phosphonophosphate group and its use for studying prenyltransferase enzymes. Inhibition kinetics, photoaffinity labeling experiments and x-ray crystallographic analysis validate this compound as a good mimic of FPP. To further explore the utility of this new analogue, photoaffinity labeling of crude protein extracts obtained from the latex of the brazilian rubber tree, Hevea brasiliensis was explored. These experiments identified the previously characterized protein, Rubber Elongation Factor, suggesting it directly interacts with FPP during rubber biosynthesis.
 

New Reactions and Methodology, Total Synthesis, Materials, Devices and Switches, Lipids, Nucleotides and Mimetics
8:00 PM-10:00 PM, Tuesday, March 27, 2007 Hyatt Regency Chicago -- Riverside Center, Poster

Division of Organic Chemistry

The 233rd ACS National Meeting, Chicago, IL, March 25-29, 2007