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The mechano-chemistry of a monomeric reverse transcriptase.

ABSTRACT: Retroviral reverse transcriptase catalyses the synthesis of an integration-competent dsDNA molecule, using as a substrate the viral RNA. Using optical tweezers, we follow the Murine Leukemia Virus reverse transcriptase as it performs strand-displacement polymerization on a template under mechanical force. Our results indicate that reverse transcriptase functions as a Brownian ratchet, with dNTP binding as the rectifying reaction of the ratchet. We also found that reverse transcriptase is a relatively passive enzyme, able to polymerize on structured templates by exploiting their thermal breathing. Finally, our results indicate that the enzyme enters the recently characterized backtracking state from the pre-translocation complex.

SUBMITTER: Malik O

PROVIDER: S-EPMC5728418 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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The mechano-chemistry of a monomeric reverse transcriptase.

Malik Omri O Khamis Hadeel H Rudnizky Sergei S Kaplan Ariel A

Nucleic acids research 20171201 22

Retroviral reverse transcriptase catalyses the synthesis of an integration-competent dsDNA molecule, using as a substrate the viral RNA. Using optical tweezers, we follow the Murine Leukemia Virus reverse transcriptase as it performs strand-displacement polymerization on a template under mechanical force. Our results indicate that reverse transcriptase functions as a Brownian ratchet, with dNTP binding as the rectifying reaction of the ratchet. We also found that reverse transcriptase is a relat ...[more]

PMID: 29165701

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