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Mononucleotide repeat expansions with non-natural polymerase substrates.

ABSTRACT: Replicative strand slippage is a biological phenomenon, ubiquitous among different organisms. However, slippage events are also relevant to non-natural replication models utilizing synthetic polymerase substrates. Strand slippage may notably affect the outcome of the primer extension reaction with repetitive templates in the presence of non-natural nucleoside triphosphates. In the current paper, we studied the ability of Taq, Vent (exo-), and Deep Vent (exo-) polymerases to produce truncated, full size, or expanded modified strands utilizing non-natural 2'-deoxyuridine nucleotide analogues and different variants of the homopolymer template. Our data suggest that the slippage of the primer strand is dependent on the duplex fluttering, incorporation efficiency for a particular polymerase-dNTP pair, rate of non-templated base addition, and presence of competing nucleotides.

SUBMITTER: Chudinov AV

PROVIDER: S-EPMC7844250 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Mononucleotide repeat expansions with non-natural polymerase substrates.

Chudinov Alexander V AV Vasiliskov Vadim A VA Kuznetsova Viktoriya E VE Lapa Sergey A SA Kolganova Natalia A NA Timofeev Edward N EN

Scientific reports 20210128 1

Replicative strand slippage is a biological phenomenon, ubiquitous among different organisms. However, slippage events are also relevant to non-natural replication models utilizing synthetic polymerase substrates. Strand slippage may notably affect the outcome of the primer extension reaction with repetitive templates in the presence of non-natural nucleoside triphosphates. In the current paper, we studied the ability of Taq, Vent (exo-), and Deep Vent (exo-) polymerases to produce truncated, fu ...[more]

PMID: 33510377

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