Enzymatic preparation of 32P-labeled beta-L-2',3',-dd-5'ATP and its use as a high-affinity, conformation-specific ligand for labeling adenylyl cyclases.
An enzymatic method was developed for the preparation of unlabeled and [beta-32P]-labeled beta-L-2',3'-dd-5'ATP from the monophosphate with near quantitative yields. beta-L-2',3'-dd-5'ATP was a competitive and potent inhibitor of adenylyl cyclases (IC5 approximately 30 nM). Upon uv-irradiation beta-L-2',3'-dd-[beta-32P]-5'ATP directly crosslinked to a chimeric construct of this enzyme. Data suggest that this is a pre-transition state inhibitor and contrasts with the equipotent 2',5'-dd-3'ATP, a post-transition state, noncompetitive inhibitor.
Johnson
R A
RA
State Univ. of New York, Stony Brook 11794, USA.
Shoshani
I
I
Dessauer
C
C
Gosselin
G
G
D000255:Adenosine Triphosphate / Q000378:metabolism* / Q000494:pharmacology; D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000737:chemistry / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism* / Q000494:pharmacology; D008024:Ligands; D010761:Phosphorus Radioisotopes; D010766:Phosphorylation; D011487:Protein Conformation
D000067956:Adenylyl Cyclase Inhibitors; D004791:Enzyme Inhibitors; D008024:Ligands; D010761:Phosphorus Radioisotopes; D000255:Adenosine Triphosphate; D000262:Adenylyl Cyclases