PDE7A1 hydrolyzes cCMP

Article ID	Journal	Published Year	Pages	File Type
10870426	FEBS Letters	2014	6 Pages	PDF

Abstract

The degradation and biological role of the cyclic pyrimidine nucleotide cCMP is largely elusive. We investigated nucleoside 3â²,5â²-cyclic monophosphate (cNMP) specificity of six different recombinant phosphodiesterases (PDEs) by using a highly-sensitive HPLC-MS/MS detection method. PDE7A1 was the only enzyme that hydrolyzed significant amounts of cCMP. Enzyme kinetic studies using purified GST-tagged truncated PDE7A1 revealed a cCMP KM value of 135Â Â±Â 19Â Î¼M. The Vmax for cCMP hydrolysis reached 745Â Â±Â 27Â nmol/(minÂ mg), which is about 6-fold higher than the corresponding velocity for adenosine 3â²,5â²-cyclic monophosphate (cAMP) degradation. In summary, PDE7A is a high-speed and low-affinity PDE for cCMP.

Keywords

U-937 PKG Sf9 A549 HEK-293 cNMP cCMP ExoY CyaA CIMP CTMP XMP Thymidine 5′-monophosphate inosine 3′,5′-cyclic monophosphate nucleoside 3′,5′-cyclic monophosphate uridine 3′,5′-cyclic monophosphate Cyclic CMP Xanthosine 5′-monophosphate UMP GST cGMP PDE GMP CMP pKa TMP AMP IMP HCN inosine 5′-monophosphate cAMP guanosine 3′,5′-cyclic monophosphate HPLC–MS HPLC–MS/MS uridine 5′-monophosphate adenosine 3′,5′-cyclic monophosphate adenosine 5′-monophosphate hexahistidine tag cUMP HIS human embryonic kidney cell line cytidine 3′,5′-cyclic monophosphate cytidine 5′-monophosphate Enzyme kinetics High performance liquid chromatography tandem mass spectrometry Phosphodiesterase Cyclic nucleotides protein kinase A protein kinase G second messenger Guanosine 5′-monophosphate