Intermodular linker flexibility revealed from crystal structures of adjacent cellulosomal cohesins of Acetivibrio cellulolyticus
- PMID: 19501595
- DOI: 10.1016/j.jmb.2009.06.006
Intermodular linker flexibility revealed from crystal structures of adjacent cellulosomal cohesins of Acetivibrio cellulolyticus
Abstract
Cellulosome complexes comprise an intercalated set of multimodular dockerin-containing enzymatic subunits connected to cohesin-containing nonenzymatic subunits called scaffoldins. The adjoining modules in each cellulosomal subunit are interconnected by a variety of linker segments of different lengths and composition. The exact role of the cellulosomal linkers has yet to be described, although it is assumed that they contribute to the architecture and action of the cellulosome by providing the protein subunits with flexibility and by providing spacers between the enzymatic modules that could enhance interactions with the cellulose substrate. Here we present four crystal structures of Acetivibrio cellulolyticus cellulosomal type II cohesins with linker extensions. Two of the structures represent two different crystal forms (trigonal and orthorhombic) of the same N-terminal cohesin module (CohB1) together with its full (6-residue) native C-terminal linker, derived from scaffoldin B. The other two structures belong to the adjacent (second) cohesin module (CohB2), each of which was crystallized with the same 6-residue linker segment, but now positioned at the N-terminus and with either a truncated (5-residue) or a full-length (45-residue) C-terminal linker, respectively. Comparison between the two CohB1 structures revealed significant differences in the conformation of their equivalent C-terminal linker segment. In one crystal form a helical conformation was observed, as opposed to an extended conformation in the other. The CohB2 structures also displayed diverse conformations in their linker segments. In these structures, different linker conformations were observed in the individual molecules within the asymmetric unit of each structure. This conformational diversity implies that the linkers may adopt alternative conformations in their natural environment, consistent with varying environmental conditions. The findings suggest that linkers can play an important role in the assembly, dynamics and function of the cellulosomal components.
Similar articles
-
Insights into cellulosome assembly and dynamics: from dissection to reconstruction of the supramolecular enzyme complex.Curr Opin Struct Biol. 2013 Oct;23(5):686-94. doi: 10.1016/j.sbi.2013.09.002. Epub 2013 Sep 27. Curr Opin Struct Biol. 2013. PMID: 24080387 Review.
-
Modular arrangement of a cellulosomal scaffoldin subunit revealed from the crystal structure of a cohesin dyad.J Mol Biol. 2010 Jun 4;399(2):294-305. doi: 10.1016/j.jmb.2010.04.013. Epub 2010 Apr 13. J Mol Biol. 2010. PMID: 20394754
-
Insights into higher-order organization of the cellulosome revealed by a dissect-and-build approach: crystal structure of interacting Clostridium thermocellum multimodular components.J Mol Biol. 2010 Mar 5;396(4):833-9. doi: 10.1016/j.jmb.2010.01.015. Epub 2010 Jan 11. J Mol Biol. 2010. PMID: 20070943
-
Cellulosomes: microbial nanomachines that display plasticity in quaternary structure.Mol Microbiol. 2007 Mar;63(6):1568-76. doi: 10.1111/j.1365-2958.2007.05640.x. Mol Microbiol. 2007. PMID: 17367380 Review.
-
Crystal structure of a type-II cohesin module from the Bacteroides cellulosolvens cellulosome reveals novel and distinctive secondary structural elements.J Mol Biol. 2005 Apr 22;348(1):1-12. doi: 10.1016/j.jmb.2005.02.024. J Mol Biol. 2005. PMID: 15808849
Cited by
-
Mapping the deformability of natural and designed cellulosomes in solution.Biotechnol Biofuels Bioprod. 2022 Jun 20;15(1):68. doi: 10.1186/s13068-022-02165-3. Biotechnol Biofuels Bioprod. 2022. PMID: 35725490 Free PMC article.
-
Nanoscale resolution of microbial fiber degradation in action.Elife. 2022 May 31;11:e76523. doi: 10.7554/eLife.76523. Elife. 2022. PMID: 35638899 Free PMC article.
-
Distinctive ligand-binding specificities of tandem PA14 biomass-sensory elements from Clostridium thermocellum and Clostridium clariflavum.Proteins. 2019 Nov;87(11):917-930. doi: 10.1002/prot.25753. Epub 2019 Jun 25. Proteins. 2019. PMID: 31162722 Free PMC article.
-
Dual binding in cohesin-dockerin complexes: the energy landscape and the role of short, terminal segments of the dockerin module.Sci Rep. 2018 Mar 22;8(1):5051. doi: 10.1038/s41598-018-23380-9. Sci Rep. 2018. PMID: 29568013 Free PMC article.
-
Diverse specificity of cellulosome attachment to the bacterial cell surface.Sci Rep. 2016 Dec 7;6:38292. doi: 10.1038/srep38292. Sci Rep. 2016. PMID: 27924829 Free PMC article.
Publication types
MeSH terms
Substances
Associated data
- Actions
- Actions
- Actions
- Actions
LinkOut - more resources
Full Text Sources