retroviral ribonuclease H;
RT/RNase H;
retroviral reverse transcriptase RNaseH;
HIV RNase H
Class
Hydrolases;
Acting on ester bonds;
Endoribonucleases producing 5'-phosphomonoesters
Reaction(IUBMB)
Endohydrolysis of RNA in RNA/DNA hybrids. Three different cleavage modes 1. sequence-specific internal cleavage of RNA [1-4]. Human immunodeficiency virus type 1 and Moloney murine leukemia virus enzymes prefer to cleave the RNA strand one nucleotide away from the RNA-DNA junction [5] 2. RNA 5'-end directed cleavage 13-19 nucleotides from the RNA end [6,7] 3. DNA 3'-end directed cleavage 15-20 nucleotides away from the primer terminus [8-10].
Comment
Comments: Retroviral reverse transcriptase is a multifunctional enzyme responsible for viral replication. To perform this task the enzyme combines two distinct activities. The polymerase domain (EC 2.7.7.49, RNA-directed DNA polymerase) occupies the N-terminal two-thirds of the reverse transcriptase whereas the ribonuclease H domain comprises the C-terminal remaining one-third [13,14]. The RNase H domain of Moloney murine leukemia virus and Human immunodeficiency virus display two metal binding sites [15-17]
Mechanism by which a glutamine to leucine substitution at residue 509 in the ribonuclease H domain of HIV-1 reverse transcriptase confers zidovudine resistance.
Beilhartz GL, Wendeler M, Baichoo N, Rausch J, Le Grice S, Gotte M
Title
HIV-1 reverse transcriptase can simultaneously engage its DNA/RNA substrate at both DNA polymerase and RNase H active sites: implications for RNase H inhibition.
