Identification and Quantification of Cyclic Di-Guanosine Monophosphate and Its Linear Metabolites by Reversed-Phase LC-MS/MS

Abstract

Cyclic dinucleotides such as bis-(3′,5′)-cyclic dimeric guanosine monophosphate (3′,3′-c-di-GMP) represent an important class of second messengers in bacteria and are involved in numerous (patho)physiological settings. Here, we describe a sensitive and specific quantification method for 3′,3′-c-di-GMP by HPLC-coupled tandem mass spectrometry (LC-MS/MS). Additionally, linear 3′,3′-c-di-GMP metabolites, i.e., 5′-phosphoguanylyl-3′,5′-guanosine (pGpG) and 5′-guanosine monophosphate (5′-GMP), as well as cyclic guanosine monophosphate (3′,5′-cGMP) and 3′,3′ c-di-GMP analogues (2′,3′-c-di-GMP and 2′,2′-c-di-GMP) can be simultaneously determined by this method.