Comparison of batch and chromatographic assays of cyclic nucleiotide phosphodiesterases.
An improved method for the assay of cyclic nucleotide phosphodiesterases (CNPases) is described in which residual 3H-cAMP or 3H-cGMP is separated from products by chromatography on thin layers of PEI-cellulose. Comparison of CNPase activity in crude or purified kidney enzyme assayed by the PEI-cellulose method with a batch anion-exchange resin method showed serious underestimation of activity by the latter method. The batch method underestimated CNPase activity by 34-82%. The error was due to substantial binding of nucleosides (adenosine and guanosine) to the resin, which is assumed not to occur by those using this method.
D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000032:analysis*; D000327:Adsorption; D000818:Animals; D000837:Anion Exchange Resins; D001665:Binding Sites; D002855:Chromatography, Thin Layer / Q000379:methods*; D000242:Cyclic AMP; D006152:Cyclic GMP; D006868:Hydrolysis; D007668:Kidney / Q000201:enzymology; D010727:Phosphoric Diester Hydrolases / Q000032:analysis*; D051381:Rats
D000837:Anion Exchange Resins; D000242:Cyclic AMP; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases; D010727:Phosphoric Diester Hydrolases; D006152:Cyclic GMP