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The Methanothermobacter thermautotrophicus MCM helicase is active as a hexameric ring
Jae-Ho Shin1, Gun-Young Heo1, Zvi Kelman1
1Division of Applied Biology and Chemistry, College of Agriculture and Life Sciences, Kyungpook National University, 1370 Sankyuk-Dong, Daegu 702-701, Republic of Korea and the University of Maryland Biotechnology Institute, Center for Advanced Research in Biotechnology, Rockville, Maryland 20850.
The Journal of Biological Chemistry
|November 13, 2008
Summary
The Methanothermobacter thermautotrophicus minichromosome maintenance (MCM) helicase functions as a hexamer. This study clarifies the archaeal MCM complex structure, resolving previous structural uncertainties.
Area of Science:
- Biochemistry
- Structural Biology
- Archaea
Background:
- The minichromosome maintenance (MCM) complex is the core replicative helicase in archaea and eukarya.
- The precise quaternary structure of the single MCM homolog in Methanothermobacter thermautotrophicus has been debated, with various oligomeric states reported.
Purpose of the Study:
- To determine the active oligomeric state of the Methanothermobacter thermautotrophicus MCM helicase.
- To resolve structural ambiguities surrounding archaeal MCM complexes.
Main Methods:
- Biochemical assays to assess helicase activity.
- Structural analysis techniques to elucidate quaternary structure.
Main Results:
- Biochemical and structural data demonstrate that the M. thermautotrophicus MCM helicase is active as a hexamer.
- This finding provides a definitive structural basis for the archaeal MCM complex.
Conclusions:
- The Methanothermobacter thermautotrophicus MCM helicase functions as a hexamer.
- This study clarifies the structure of a key component of the archaeal DNA replication machinery.
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