title: Crystallization and preliminary X-ray characterization of a type III cohesin-dockerin complex from the cellulosome system of Ruminococcus flavefaciens.
abstract: In Ruminococcus flavefaciens, a predominant fibre-degrading bacterium found in ruminants, cellulosomal proteins are anchored to the bacterial cell wall through a relatively small ScaE scaffoldin which includes a single type III cohesin. The cotton-binding protein CttA consists of two cellulose-binding modules and a C-terminal modular pair (XDoc) comprising an X-module and a contiguous dockerin, which exhibits high affinity towards the ScaE cohesin. Seleno-L-methionine-labelled derivatives of the ScaE cohesin module and the XDoc from CttA have been expressed, copurified and cocrystallized. The crystals belonged to the tetragonal space group P4(3)2(1)2, with unit-cell parameters a = b = 78.7, c = 203.4 Å, and the unit cell contains a single cohesin-XDoc complex in the asymmetric unit. The diffraction data were phased to 2.0 Å resolution using the anomalous signal of the Se atoms.
authors.affiliation: Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Orly
authors.initials: O
authors.lastname: Salama-Alber
authors.forename: Yair
authors.initials: Y
authors.lastname: Gat
authors.forename: Raphael
authors.initials: R
authors.lastname: Lamed
authors.forename: Linda J W
authors.initials: LJ
authors.lastname: Shimon
authors.forename: Edward A
authors.initials: EA
authors.lastname: Bayer
authors.forename: Felix
authors.initials: F
authors.lastname: Frolow
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000737:chemistry* / Q000378:metabolism; D044603:Cellulosomes / Q000737:chemistry* / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000737:chemistry* / Q000378:metabolism; D003460:Crystallization; D018360:Crystallography, X-Ray; D011485:Protein Binding; D045857:Ruminococcus / Q000737:chemistry* / Q000378:metabolism; D000097722:Cohesins
chemical_list: D001426:Bacterial Proteins; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D000097722:Cohesins