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The MukF subunit of Escherichia coli condensin: architecture and functional relationship to kleisins.

ABSTRACT: The Escherichia coli MukB, MukE, and MukF proteins form a bacterial condensin (MukBEF) that contributes to chromosome management by compacting DNA. MukB is an ATPase and DNA-binding protein of the SMC superfamily; however, the structure and function of non-SMC components, such as MukF, have been less forthcoming. Here, we report the crystal structure of the N-terminal 287 amino acids of MukF at 2.9 A resolution. This region folds into a winged-helix domain and an extended coiled-coil domain that self-associate to form a stable, doubly domain-swapped dimer. Protein dissection and affinity purification data demonstrate that the region of MukF C-terminal to this fragment binds to MukE and MukB. Our findings, together with sequence analyses, indicate that MukF is a kleisin subunit for E. coli condensin and suggest a means by which it may organize the MukBEF assembly.

SUBMITTER: Fennell-Fezzie R

PROVIDER: S-EPMC1142612 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature

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The MukF subunit of Escherichia coli condensin: architecture and functional relationship to kleisins.

Fennell-Fezzie Rachel R Gradia Scott D SD Akey David D Berger James M JM

The EMBO journal 20050519 11

The Escherichia coli MukB, MukE, and MukF proteins form a bacterial condensin (MukBEF) that contributes to chromosome management by compacting DNA. MukB is an ATPase and DNA-binding protein of the SMC superfamily; however, the structure and function of non-SMC components, such as MukF, have been less forthcoming. Here, we report the crystal structure of the N-terminal 287 amino acids of MukF at 2.9 A resolution. This region folds into a winged-helix domain and an extended coiled-coil domain that ...[more]

PMID: 15902272

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2018-02-01 | GSE103937 | GEO

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