3L8Q

Structure analysis of the type II cohesin dyad from the adaptor ScaA scaffoldin of Acetivibrio cellulolyticus

Summary for 3L8Q

• Entry DOI: 10.2210/pdb3l8q/pdb
• Related: 1ZV9 3FNK
• Descriptor: Cellulosomal scaffoldin adaptor protein B, 1,2-ETHANEDIOL, 1,3-PROPANDIOL, ... (5 entities in total)
• Functional Keywords: dockerin-binding module, protein-protein interactions, linker segment, scaffoldin arrangement, beta sandwich, alpha helix, beta flaps, structural protein, protein binding
• Biological source: Acetivibrio cellulolyticus
• Total number of polymer chains: 4
• Total formula weight: 153535.90

Authors

Noach, I.,Frolow, F.,Bayer, E.A. (deposition date: 2010-01-03, release date: 2010-05-05, Last modification date: 2023-11-01)

Primary citation

Noach, I.,Levy-Assaraf, M.,Lamed, R.,Shimon, L.J.W.,Frolow, F.,Bayer, E.A.
Modular Arrangement of a Cellulosomal Scaffoldin Subunit Revealed from the Crystal Structure of a Cohesin Dyad
J.Mol.Biol., 399:294-305, 2010

PubMed Abstract: The cellulosome complex is composed of a conglomerate of subunits, each of which comprises a set of interacting functional modules. Scaffoldin (Sca), a major cellulosomal subunit, is responsible for organizing the cellulolytic subunits into the complex. This is accomplished by the interaction of two complementary classes of modules-a cohesin (Coh) module on the Sca subunit and a dockerin module on each of the enzymatic subunits. Although individual Coh modules from different cellulosomal scaffoldins have been subjected to intensive structural investigation, the Sca subunit in its entirety has not, and there remains a paucity of information on the arrangement and interactions of Cohs within the Sca subunit. In the present work, we describe the crystal structure of a type II Coh dyad from the ScaB "adaptor" Sca of Acetivibrio cellulolyticus. The ScaB Cohs are oriented in an "antiparallel" manner relative to one another, with their dockerin-interacting surfaces (beta-strands 8-3-6-5) facing the same direction-aligned on the same plane. A set of extensive hydrophobic and hydrogen-bond contacts between the Cohs and the short interconnecting linker segment between them stabilizes the modular orientation. This Coh dyad structure provides novel information about Coh-Coh association and arrangement in the Sca and further insight into intermodular linker interactions. Putative structural arrangements of a hexamodular complex, composed of the Coh dyad bound to two X-dockerin modules, were suggested.

PubMed: 20394754
DOI: 10.1016/j.jmb.2010.04.013

Experimental method

X-RAY DIFFRACTION (1.57 Å)