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Structural characterization of a novel autonomous cohesin from Ruminococcus flavefaciens.

ABSTRACT: Ruminococcus flavefaciens is a cellulolytic bacterium found in the rumen of herbivores and produces one of the most elaborate and variable cellulosome systems. The structure of an R. flavefaciens protein (RfCohG, ZP_06142108), representing a freestanding (non-cellulosomal) type III cohesin module, has been determined. A selenomethionine derivative with a C-terminal histidine tag was crystallized and diffraction data were measured to 2.44?Å resolution. Its structure was determined by single-wavelength anomalous dispersion, revealing eight molecules in the asymmetric unit. RfCohG exhibits the most complex among all known cohesin structures, possessing four ?-helical elements and a topographical protuberance on the putative dockerin-binding surface.

SUBMITTER: Voronov-Goldman M

PROVIDER: S-EPMC3976060 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Structural characterization of a novel autonomous cohesin from Ruminococcus flavefaciens.

Voronov-Goldman Milana M Levy-Assaraf Maly M Yaniv Oren O Wisserman Gloria G Jindou Sadanari S Borovok Ilya I Bayer Edward A EA Lamed Raphael R Shimon Linda J W LJ Frolow Felix F

Acta crystallographica. Section F, Structural biology communications 20140325 Pt 4

Ruminococcus flavefaciens is a cellulolytic bacterium found in the rumen of herbivores and produces one of the most elaborate and variable cellulosome systems. The structure of an R. flavefaciens protein (RfCohG, ZP_06142108), representing a freestanding (non-cellulosomal) type III cohesin module, has been determined. A selenomethionine derivative with a C-terminal histidine tag was crystallized and diffraction data were measured to 2.44 Å resolution. Its structure was determined by single-wavel ...[more]

PMID: 24699736

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