3ZGX

Crystal structure of the kleisin-N SMC interface in prokaryotic condensin

Summary for 3ZGX

• Entry DOI: 10.2210/pdb3zgx/pdb
• Descriptor: CHROMOSOME PARTITION PROTEIN SMC, SEGREGATION AND CONDENSATION PROTEIN A (2 entities in total)
• Functional Keywords: cell cycle
• Biological source: BACILLUS SUBTILIS; More
• Cellular location: Cytoplasm: P51834 P35154
• Total number of polymer chains: 4
• Total formula weight: 118699.12

Authors

Burmann, F.,Shin, H.,Basquin, J.,Soh, Y.,Gimenez, V.,Kim, Y.,Oh, B.,Gruber, S. (deposition date: 2012-12-19, release date: 2013-01-30, Last modification date: 2024-05-08)

Primary citation

Burmann, F.,Shin, H.,Basquin, J.,Soh, Y.,Gimenez-Oya, V.,Kim, Y.,Oh, B.,Gruber, S.
An Asymmetric Smc-Kleisin Bridge in Prokaryotic Condensin.
Nat.Struct.Mol.Biol., 20:371-, 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 (3.4 Å)