4I99

Crystal structure of the SmcHead bound to the C-winged helix domain of ScpA

Summary for 4I99

• Entry DOI: 10.2210/pdb4i99/pdb
• Related: 4I98
• Descriptor: Chromosome partition protein Smc, Putative uncharacterized protein, PHOSPHATE ION, ... (4 entities in total)
• Functional Keywords: winged-helix domain and smc head domain, chromosome condensation, scpb, dna binding protein
• Biological source: Pyrococcus furiosus; More
• Cellular location: Cytoplasm : Q8TZY2
• Total number of polymer chains: 4
• Total formula weight: 100809.83

Authors

Shin, H.C.,Soh, Y.M.,Oh, B.H. (deposition date: 2012-12-05, release date: 2013-01-30, Last modification date: 2024-11-20)

Primary citation

Burmann, F.,Shin, H.C.,Basquin, J.,Soh, Y.M.,Gimenez-Oya, V.,Kim, Y.G.,Oh, B.H.,Gruber, S.
An asymmetric SMC-kleisin bridge in prokaryotic condensin.
Nat.Struct.Mol.Biol., 20:371-379, 2013

PubMed Abstract: Eukaryotic structural maintenance of chromosomes (SMC)-kleisin complexes form large, ring-shaped assemblies that promote accurate chromosome segregation. Their asymmetric structural core comprises SMC heterodimers that associate with both ends of a kleisin subunit. However, prokaryotic condensin Smc-ScpAB is composed of symmetric Smc homodimers associated with the kleisin ScpA in a postulated symmetrical manner. Here, we demonstrate that Smc molecules have two distinct binding sites for ScpA. The N terminus of ScpA binds the Smc coiled coil, whereas the C terminus binds the Smc ATPase domain. We show that in Bacillus subtilis cells, an Smc dimer is bridged by a single ScpAB to generate asymmetric tripartite rings analogous to eukaryotic SMC complexes. We define a molecular mechanism that ensures asymmetric assembly, and we conclude that the basic architecture of SMC-kleisin rings evolved before the emergence of eukaryotes.

PubMed: 23353789
DOI: 10.1038/nsmb.2488

Experimental method

X-RAY DIFFRACTION (2.3 Å)