The crystal structure of the hinge domain of the Escherichia coli structural maintenance of chromosomes protein MukB.
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.
Department of Chemistry, Indiana University, Bloomington, IN 47405, USA.
Yinyin
Y
Li
Allyn J
AJ
Schoeffler
James M
JM
Berger
Martha G
MG
Oakley
D000595:Amino Acid Sequence; D002868:Chromosomal Proteins, Non-Histone / Q000737:chemistry*; D002876:Chromosomes, Bacterial / Q000378:metabolism*; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary
D002868:Chromosomal Proteins, Non-Histone; D029968:Escherichia coli Proteins; C067035:MukB protein, E coli