2′,3′-Dideoxynucleoside triphosphates (ddNTP) and di-2′,3′-dideoxynucleoside tetraphosphates (ddNp_4ddN) behave differently to the corresponding NTP and Np_4N counterparts as substrates of firefly luciferase, dinucleoside tetraphosphatase and pho

摘要

2′,3′-Dideoxynucleosides (ddN) and their derivatives are currently used as antiretroviral compounds. Their active agents are the corresponding 2′,3′-dideoxynucleoside triphosphates (ddNTPs) generated inside the cell by host kinases. Dinucleoside tetraphosphates (Np4Ns) are molecules of interest in metabolic regulation; their synthesis in vitro can be catalyzed by firefly luciferase. The relative synthesis of diadenosine 5′,5-P1,P4-tetraphosphate or adenosine(5′)tetraphospho(5′)adenosine (Ap4A) from ATP is about 100-fold faster than that of di-2′,3′-dideoxyadenosine 5′,5-P1,P4-tetraphosphate or 2′,3′-dideoxyadenosine (5′)tetraphospho (5′)-2′,3′-dideoxyadenosine (ddAp4ddA) from ddATP. In the presence of ATPγS and ddATP the yield of adenosine(5′)tetraphospo(5′)-2′,3′-dideoxyadenosine (Ap4ddA) was similar to that attained for Ap4A in the presence of ATP. The findings of this work indicate that the presence of a 3′-hydroxyl group is essential for the formation of the luciferase-luciferin-AMP complex, and explains the very low yield of ddAp4ddA in the presence of luciferase, luciferin and ddATP. The absence of 3′-hydroxyl groups in ddAp4ddA greatly hindered their hydrolysis by snake venom phosphodiesterase, asymmetrical dinucleoside tetraphosphatase and by a purified membrane preparation from rat liver. The possibility of using di-2′,3′-dideoxynucleoside tetraphosphate (ddNp4ddN) or nucleoside(5′)tetraphospho(5′)-2′,3′-dideoxynucleoside (Np4ddN) as a source of the active retroviral agent ddNTP, for example in HIV infection, is outlined.