Dataset Information

High-temperature single-molecule kinetic analysis of thermophilic archaeal MCM helicases.

ABSTRACT: The minichromosome maintenance (MCM) complex is the replicative helicase responsible for unwinding DNA during archaeal and eukaryal genome replication. To mimic long helicase events in the cell, a high-temperature single-molecule assay was designed to quantitatively measure long-range DNA unwinding of individual DNA helicases from the archaeons Methanothermobacter thermautotrophicus (Mth) and Thermococcus sp. 9°N (9°N). Mth encodes a single MCM homolog while 9°N encodes three helicases. 9°N MCM3, the proposed replicative helicase, unwinds DNA at a faster rate compared to 9°N MCM2 and to Mth MCM. However, all three MCM proteins have similar processivities. The implications of these observations for DNA replication in archaea and the differences and similarities among helicases from different microorganisms are discussed. Development of the high-temperature single-molecule assay establishes a system to comprehensively study thermophilic replisomes and evolutionary links between archaeal, eukaryal, and bacterial replication systems.

SUBMITTER: Schermerhorn KM

PROVIDER: S-EPMC5062978 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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High-temperature single-molecule kinetic analysis of thermophilic archaeal MCM helicases.

Schermerhorn Kelly M KM Tanner Nathan N Kelman Zvi Z Gardner Andrew F AF

Nucleic acids research 20160705 18

The minichromosome maintenance (MCM) complex is the replicative helicase responsible for unwinding DNA during archaeal and eukaryal genome replication. To mimic long helicase events in the cell, a high-temperature single-molecule assay was designed to quantitatively measure long-range DNA unwinding of individual DNA helicases from the archaeons Methanothermobacter thermautotrophicus (Mth) and Thermococcus sp. 9°N (9°N). Mth encodes a single MCM homolog while 9°N encodes three helicases. 9°N MCM3 ...[more]

PMID: 27382065

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Dataset Information

High-temperature single-molecule kinetic analysis of thermophilic archaeal MCM helicases.

Publications

High-temperature single-molecule kinetic analysis of thermophilic archaeal MCM helicases.

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