title: A simple, sensitive protein-binding assay for guanosine 3':5'-monophosphate.
abstract: A protein-binding assay for guanosine 3':5'-monophosphate, which employs an enzyme preparation from lobster tail muscle, is described. The binding constant for cyclic GMP was 2-10 nM for four different enzyme preparations. The method can be set up in several days and permits the detection of as little as 0.5-1 pmol of cyclic GMP. In some instances, it is possible to assay the nucleotide in urine or deproteinized extracts of tissue without purification. For other samples, a simple method for separating and purifying cyclic AMP and cyclic GMP is described.
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000032:analysis; D003445:Crustacea / Q000201:enzymology; D000242:Cyclic AMP / Q000302:isolation & purification; D006152:Cyclic GMP / Q000032:analysis / Q000652:urine; D004798:Enzymes / Q000494:pharmacology; D006150:Guanine Nucleotides / Q000032:analysis*; D008099:Liver / Q000032:analysis; D008168:Lung / Q000032:analysis; D008297:Male; D008722:Methods; D011485:Protein Binding; D011506:Proteins; D051381:Rats; D014316:Tritium
chemical_list: D004798:Enzymes; D006150:Guanine Nucleotides; D011506:Proteins; D014316:Tritium; D000242:Cyclic AMP; D006152:Cyclic GMP