Required for chromosome condensation and partitioning (By similarity). Binds single-stranded but not double-stranded DNA. Homodimer. Contains large globular domains required for ATP hydrolysis at each terminus and a third globular domain forming a flexible SMC hinge near the middle of the molecule. These domains are separated by coiled-coil structures. The N- and C-terminus interact to make up an ATP-binding cassette-type ATPase domain. The SMC hinge domain mediates dimerization and binds DNA. Belongs to the SMC family. Extended N-terminus.