Inhibition of cGMP-dependent protein kinase by (Rp)-guanosine 3',5'-monophosphorothioates

• Published in: FEBS letters 1990-04, Vol.263 (1), p.47-50
• Main Authors: Butt, Elke, Van Bemmelen, Michael, Fischer, Lilo, Walter, Ulrich, Jastorff, Bernd
• Format: Article
• Language: English
• Subjects: (Rp)- and (Sp)-8-Cl-cGMPS, phosphorothioate stereoisomers of 8-chloro-cGMP; (Rp)- and (Sp)-cAMPS, phosphorothioate stereoisomers of cAMP; (Rp)- and (Sp)-cGMPS, phosphorothioate stereoisomers of cGMP; (Rp)-guanosine 3',5'-monophosphorothioates; 8-Cl-cGMP, 8-chloro-8-cGMP; 8-Cl-cGMPS; Analytical, structural and metabolic biochemistry; Animals; Antagonist; Biological and medical sciences; cAK, cAMP-dependent protein kinase; Cattle; cGK, cGMP-dependent protein kinase; cGMPS; cPDE, calmodulin-sensitive cyclic nucleotide phosphodiesterase; cyclic GMP; Cyclic GMP - analogs & derivatives; Cyclic GMP - pharmacology; dependent; Enzyme Activation; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; inactivation; Kinetics; lung; Lung - enzymology; Molecular Structure; Myocardium - enzymology; protein kinase; Protein Kinase Inhibitors; Protein kinase, cGMP-dependent; Protein Kinases - metabolism; Stereoisomerism; Structure-Activity Relationship; Thionucleotides - pharmacology; Transferases
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(90)80702-K

The activation of the cGMP-dependent protein kinase and cAMP-dependent protein kinase by the diastereomers of guanosine 3',5'-monophosphorothioate, (Sp)-cGMPS and (Rp)-cGMPS, and 8-chloroguanosine 3',5'-monophosphorothioate, (Sp)-8-Cl-cGMPS and (Rp)-8-Cl-cGMPS, was investigated using the peptide Kemptide as substrate. The (Sp)-diastereomers, which have an axial exocyclic sulfur atom, bound to the cGMP-dependent protein kinase and stimulated its phosphotransferase activity. In contrast, the (Rp)-isomers, which have an equatorial exocyclic sulfur atom, bound to the enzyme without stimulation of its activity. (Rp)-cGMPS and (Rp)-8-Cl-cGMPS antagonized the activation of the cGMP-dependent protein kinase with a K i of 20 μM and 1.5 μM, respectively. (Rp)-cGMPS also antagonized the activation of cAMP-dependent protein kinase with a K i of 20 μM. In contrast, (Rp)-8-Cl-cGMPS was a weak inhibitor of the cAMP-dependent protein kinase with a K i of 100 μM. (Rp)-8-Cl-cGMPS appears to be a rather selective inhibitor of the cGMP-dependent protein kinase and may be a useful tool for studying the role of cGMP in broken and intact cell systems.