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Structure of an octameric form of the minichromosome maintenance protein from the archaeon Pyrococcus abyssi.

ABSTRACT: Cell division is a complex process that requires precise duplication of genetic material. Duplication is concerted by replisomes. The Minichromosome Maintenance (MCM) replicative helicase is a crucial component of replisomes. Eukaryotic and archaeal MCM proteins are highly conserved. In fact, archaeal MCMs are powerful tools for elucidating essential features of MCM function. However, while eukaryotic MCM2-7 is a heterocomplex made of different polypeptide chains, the MCM complexes of many Archaea form homohexamers from a single gene product. Moreover, some archaeal MCMs are polymorphic, and both hexameric and heptameric architectures have been reported for the same polypeptide. Here, we present the structure of the archaeal MCM helicase from Pyrococcus abyssi in its single octameric ring assembly. To our knowledge, this is the first report of a full-length octameric MCM helicase.

SUBMITTER: Cannone G

PROVIDER: S-EPMC5296750 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Structure of an octameric form of the minichromosome maintenance protein from the archaeon Pyrococcus abyssi.

Cannone Giuseppe G Visentin Silvia S Palud Adeline A Henneke Ghislaine G Spagnolo Laura L

Scientific reports 20170208

Cell division is a complex process that requires precise duplication of genetic material. Duplication is concerted by replisomes. The Minichromosome Maintenance (MCM) replicative helicase is a crucial component of replisomes. Eukaryotic and archaeal MCM proteins are highly conserved. In fact, archaeal MCMs are powerful tools for elucidating essential features of MCM function. However, while eukaryotic MCM2-7 is a heterocomplex made of different polypeptide chains, the MCM complexes of many Archa ...[more]

PMID: 28176822

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