tailieunhanh - Báo cáo khoa học: Halogenated benzimidazoles and benzotriazoles as inhibitors of the NTPase/helicase activities of hepatitis C and related viruses

A search has been initiated for lead inhibitors of the non-structural protein 3 (NS3)-associated NTPase/helicase activities of hepatitis C virus,the related West Nile virus, Japanese encephalitis virus and the human mitochondrial Suv3 enzyme. Random screening of a broad range of unre-lated low-molecular mass compounds,employing both RNA and DNA substrates, revealed that 4,5,6,7-tetra-bromobenzotriazole (TBBT) hitherto known as a potent highly selective inhibitor of protein kinase 2,is a good inhibitor of the helicase,but not NTPase,activity of hepa-titis C virus NTPase/helicase. . | Eur. J. Biochem. 270 1645-1653 2003 FEBS 2003 doi Halogenated benzimidazoles and benzotriazoles as inhibitors of the NTPase helicase activities of hepatitis C and related viruses Peter Borowski1 Johanna Deinert1 Sarah Schalinski1 Maria Bretner2 Krzysztof Ginalski3 4 Tadeusz Kulikowski2 and David Shugar2 4 1Abteilung fur Virologie Bernhard-Nocht-Institut fur Tropenmedizin Hamburg Germany institute of Biochemistry Biophysics Polish Academy of Sciences Warsaw Poland 3BioInfoBank Poznan Poland 4ICM University of Warsaw Poland A search has been initiated for lead inhibitors of the non-structural protein 3 NS3 -associated NTPase helicase activities of hepatitis C virus the related West Nhe virus Japanese encephalitis virus and the human mitochondrial Suv3 enzyme. Random screening of a broad range of unrelated low-molecular mass compounds employing botìi RNA and DNA substrates revealed that 4 5 6 7-tetra-bromobenzotriazole TBBT hitherto known as a potent highly selective inhibitor of protein kinase 2 is a oodd inhibitor of the helicase but not NTPase activity of hepatitis C virus NTPase helicase. The IC50 is approximately 20 M with a DNA substrate hut only 50 M with an RNA substrate. Several related analogues of TBBT were enzyme-and or substrate-specific inhibitors. For example 5di-di-chloro-1- P-D-ribofuranosyl benzotriazole DRBT was a good and seeectivei mhibitor oShhe West Nfie viuus nnzmne with an RNA substrate IC50 M but much weaker with a DNA substrate IC50 3 M . Preincubation of the enzymes but not substrates with DRBT enhanced inhibi tory potency . the IC50 vs the hepatitis C virus helicase activity was reduced from to M. No effect of preincubation was noted with TBBT lngaestmg a diSleinnt mode of interaction with the enzyme. The tetrachloro congener of TBBT 4 5 6 7 -tetrachlorobenzotriazole TCBT a much weaker inhibitor of casein kinase 2 is also a much weaker inhibitor than TBBT of all four helicases. Kinetic .