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The crystal structure of the hinge domain of the Escherichia coli structural maintenance of chromosomes protein MukB.

ABSTRACT: MukB, a divergent structural maintenance of chromosomes (SMC) protein, is important for chromosomal segregation and condensation in gamma-proteobacteria. MukB and canonical SMC proteins share a characteristic five-domain structure. Globular N- and C-terminal domains interact to form an ATP-binding cassette-like ATPase or "head" domain, which is connected to a smaller dimerization or "hinge" domain by a long, antiparallel coiled coil. In addition to mediating dimerization, this hinge region has been implicated in both conformational flexibility and dynamic protein-DNA interactions. We report here the first crystallographic model of the MukB hinge domain. This model also contains approximately 20% of the coiled-coil domain, including an unusual coiled-coil deviation. These results will facilitate studies to clarify the roles of both the hinge and the coiled-coil domains in MukB function.

SUBMITTER: Li Y

PROVIDER: S-EPMC4335309 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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The crystal structure of the hinge domain of the Escherichia coli structural maintenance of chromosomes protein MukB.

Li Yinyin Y Schoeffler Allyn J AJ Berger James M JM Oakley Martha G MG

Journal of molecular biology 20091022 1

MukB, a divergent structural maintenance of chromosomes (SMC) protein, is important for chromosomal segregation and condensation in gamma-proteobacteria. MukB and canonical SMC proteins share a characteristic five-domain structure. Globular N- and C-terminal domains interact to form an ATP-binding cassette-like ATPase or "head" domain, which is connected to a smaller dimerization or "hinge" domain by a long, antiparallel coiled coil. In addition to mediating dimerization, this hinge region has b ...[more]

PMID: 19853611

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