title: Determination of phosphodiesterase activity in the presence of phosphomonoesterase using bis-p-nitrophenyl phosphate.
abstract: In the presence of phosphomonoesterase contaminations the use of bis-p-nitrophenyl phosphate to measure phosphodiesterase activity gives inconclusive values because one of the products of the phosphodiesterase or nuclease reaction becomes a substrate of the contaminating enzyme. A direct determination of the hydrolyzed phosphodiesterase substrate in the UV range is possible at the isosbestic points of the transformation of the phosphomonoesterase substrate.
mesh_terms: D009596:Nitrophenols; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D013053:Spectrophotometry / Q000379:methods*; D013379:Substrate Specificity
chemical_list: D009596:Nitrophenols; D010744:Phosphoric Monoester Hydrolases; D010727:Phosphoric Diester Hydrolases