The effect of certain <i>N</i>-tritylated phenylalanine conjugates of amino-adenosine-3’,5’-cyclic monophosphate on Moloney murine leukaemia virus reverse transcriptase activity

  • Johann M. van Zyl Stellenbosch University
  • Mario Ariatti University of KwaZula-Natal
  • Arthur O. Hawtrey Stellenbosch University
Keywords: inhibitor, Moloney murine leukaemia virus, N-tritylated phenylalanine-nucleotide, reverse transcriptase, ribose-sugar

Abstract

Moloney murine leukaemia virus (M-MuLV) is a member of the retrovirus family. Its cloned reverse transcriptase (RT), similarly to HIV type 1 reverse transcriptase (HIV-1 RT), exhibits DNA-polymerase and ribonuclease H (RNase H) activities capable of converting the single-stranded retroviral RNA genome into double-stranded DNA. The latter is then integrated into the host chromosome during viral infection. M-MuLV RT is, therefore, an attractive enzyme to help understand mutations in HIV-1 RT and its use in inhibition studies can help facilitate new drug designs. In this study, conjugates consisting of N-trityl derivatives of p-fluoro, p-nitro and p-iodo-DL-phenylalanine were coupled to 8-(6-aminohexyl) amino-adenosine-3’,5’-cyclic monophosphate and examined for their effect on DNA synthesis by M-MuLV RT. Synthesis was studied in a system containing poly (rA).oligo d(pT)15 as a template-primer with [3H] dTTP. The iodo-derivative, N-trityl-p-iodo-DL-phenylalanine-8-(6-aminohexyl) amino-adenosine-3’,5’-cyclic monophosphate was found to be a very active inhibitor of the RT enzyme (IC50 = 1 µM), while the p-nitro (IC50 = 45 µM) and p-fluoro (IC50 = 65 µM) were weak inhibitors. Further work will be aimed at determining the mode of binding of the N-tritylated conjugates and also of various substituted amino acids and short peptides to M-MuLV RT to elucidate the mechanisms of inhibition.

Author Biographies

Johann M. van Zyl, Stellenbosch University

Associate Professor

a Division of Pharmacology, Department of Medicine, Faculty of Health Sciences, Stellenbosch University, P O Box 19063, Tygerberg 7505, South Africa.

Mario Ariatti, University of KwaZula-Natal

Professor

b Department of Biochemistry, Westville Campus, University of KwaZula-Natal, Durban 4000, South Africa.

Arthur O. Hawtrey, Stellenbosch University

Professor

Division of Pharmacology, Department of Medicine, Faculty of Health Sciences, Stellenbosch University, P O Box 19063, Tygerberg 7505, South Africa.

Published
2010-07-05