3F9V

Crystal Structure Of A Near Full-Length Archaeal MCM: Functional Insights For An AAA+ Hexameric Helicase

Summary for 3F9V

• Entry DOI: 10.2210/pdb3f9v/pdb
• Descriptor: Minichromosome maintenance protein MCM (1 entity in total)
• Functional Keywords: replicative helicase, dna replication, mcm complex, aaa+ protein, atp-binding, dna-binding, helicase, hydrolase, nucleotide-binding
• Biological source: Sulfolobus solfataricus
• Total number of polymer chains: 1
• Total formula weight: 67318.62

Authors

Chen, X.J.,Brewster, A.S.,Wang, G.G.,Yu, X.,Greenleaf, W.,Tjajadi, M.,Klein, M. (deposition date: 2008-11-14, release date: 2008-12-30, Last modification date: 2023-12-27)

Primary citation

Brewster, A.S.,Wang, G.,Yu, X.,Greenleaf, W.B.,Carazo, J.M.,Tjajadia, M.,Klein, M.G.,Chen, X.S.
Crystal structure of a near-full-length archaeal MCM: Functional insights for an AAA+ hexameric helicase.
Proc.Natl.Acad.Sci.USA, 105:20191-20196, 2008

PubMed Abstract: The minichromosome maintenance protein (MCM) complex is an essential replicative helicase for DNA replication in Archaea and Eukaryotes. Whereas the eukaryotic complex consists of 6 homologous proteins (MCM2-7), the archaeon Sulfolobus solfataricus has only 1 MCM protein (ssoMCM), 6 subunits of which form a homohexamer. Here, we report a 4.35-A crystal structure of the near-full-length ssoMCM. The structure shows an elongated fold, with 5 subdomains that are organized into 2 large N- and C-terminal domains. A near-full-length ssoMCM hexamer generated based on the 6-fold symmetry of the N-terminal Methanothermobacter thermautotrophicus (mtMCM) hexamer shows intersubunit distances suitable for bonding contacts, including the interface around the ATP pocket. Four unusual beta-hairpins of each subunit are located inside the central channel or around the side channels in the hexamer. Additionally, the hexamer fits well into the double-hexamer EM map of mtMCM. Our mutational analysis of residues at the intersubunit interfaces and around the side channels demonstrates their critical roles for hexamerization and helicase function. These structural and biochemical results provide a basis for future study of the helicase mechanisms of the archaeal and eukaryotic MCM complexes in DNA replication.

PubMed: 19073923
DOI: 10.1073/pnas.0808037105

Experimental method

X-RAY DIFFRACTION (4.35 Å)