5NRK

Crystal structure of the sixth cohesin from Acetivibrio cellulolyticus' scaffoldin B in complex with Cel5 dockerin S15I, I16N mutant

5NRK の概要

• エントリーDOI: 10.2210/pdb5nrk/pdb
• 分子名称: Endoglucanase, DocCel5: Type I dockerin repeat domain from A. cellulolyticus family 5 endoglucanase WP_010249057 S15I, I16N mutant, CALCIUM ION, ... (6 entities in total)
• 機能のキーワード: cellulosome, cohesin, dockerin, type i cohesin-dockerin, coh-doc, protein-protein interaction, protein binding
• 由来する生物種: Acetivibrio cellulolyticus; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 45076.80

構造登録者

Bule, P.,Najmudin, S.,Fontes, C.M.G.A.,Alves, V.D. (登録日: 2017-04-24, 公開日: 2018-01-31, 最終更新日: 2024-01-17)

主引用文献

Bule, P.,Cameron, K.,Prates, J.A.M.,Ferreira, L.M.A.,Smith, S.P.,Gilbert, H.J.,Bayer, E.A.,Najmudin, S.,Fontes, C.M.G.A.,Alves, V.D.
Structure-function analyses generate novel specificities to assemble the components of multienzyme bacterial cellulosome complexes.
J. Biol. Chem., 293:4201-4212, 2018

PubMed Abstract: The cellulosome is a remarkably intricate multienzyme nanomachine produced by anaerobic bacteria to degrade plant cell wall polysaccharides. Cellulosome assembly is mediated through binding of enzyme-borne dockerin modules to cohesin modules of the primary scaffoldin subunit. The anaerobic bacterium produces a highly intricate cellulosome comprising an adaptor scaffoldin, ScaB, whose cohesins interact with the dockerin of the primary scaffoldin (ScaA) that integrates the cellulosomal enzymes. The ScaB dockerin selectively binds to cohesin modules in ScaC that anchors the cellulosome onto the cell surface. Correct cellulosome assembly requires distinct specificities displayed by structurally related type-I cohesin-dockerin pairs that mediate ScaC-ScaB and ScaA-enzyme assemblies. To explore the mechanism by which these two critical protein interactions display their required specificities, we determined the crystal structure of the dockerin of a cellulosomal enzyme in complex with a ScaA cohesin. The data revealed that the enzyme-borne dockerin binds to the ScaA cohesin in two orientations, indicating two identical cohesin-binding sites. Combined mutagenesis experiments served to identify amino acid residues that modulate type-I cohesin-dockerin specificity in Rational design was used to test the hypothesis that the ligand-binding surfaces of ScaA- and ScaB-associated dockerins mediate cohesin recognition, independent of the structural scaffold. Novel specificities could thus be engineered into one, but not both, of the ligand-binding sites of ScaB, whereas attempts at manipulating the specificity of the enzyme-associated dockerin were unsuccessful. These data indicate that dockerin specificity requires critical interplay between the ligand-binding surface and the structural scaffold of these modules.

PubMed: 29367338
DOI: 10.1074/jbc.RA117.001241

実験手法

X-RAY DIFFRACTION (1.45 Å)