Assembly of Ruminococcus flavefaciens cellulosome revealed by structures of two cohesin-dockerin complexes

DOI: 10.1038/s41598-017-00919-w

Authors: Pedro Bule (CIISA-Faculdade de Medicina Veterinária, Universidade de Lisboa) , Victor Alves (CIISA-Faculdade de Medicina Veterinária, Universidade de Lisboa) , Vered Israeli-Ruimy (The Weizmann Institute of Science) , Ana Luisa Carvalho (UCIBIO-REQUIMTE) , Luís M. A. Ferreira (CIISA – Faculdade de Medicina Veterinária) , Steven P. Smith (Queen’s University) , Harry J. Gilbert (Newcastle University) , Shabir Najmudin (CIISA – Faculdade de Medicina Veterinária) , Edward A. Bayer (The Weizmann Institute of Science) , Carlos M. G. A. Fontes (CIISA – Faculdade de Medicina Veterinária)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Scientific Reports , VOL 7

State: Published (Approved)
Published: April 2017
Diamond Proposal Number(s): 8425

Abstract: Cellulosomes are sophisticated multi-enzymatic nanomachines produced by anaerobes to effectively deconstruct plant structural carbohydrates. Cellulosome assembly involves the binding of enzyme-borne dockerins (Doc) to repeated cohesin (Coh) modules located in a non-catalytic scaffoldin. Docs appended to cellulosomal enzymes generally present two similar Coh-binding interfaces supporting a dual-binding mode, which may confer increased positional adjustment of the different complex components. Ruminococcus flavefaciens’ cellulosome is assembled from a repertoire of 223 Doc-containing proteins classified into 6 groups. Recent studies revealed that Docs of groups 3 and 6 are recruited to the cellulosome via a single-binding mode mechanism with an adaptor scaffoldin. To investigate the extent to which the single-binding mode contributes to the assembly of R. flavefaciens cellulosome, the structures of two group 1 Docs bound to Cohs of primary (ScaA) and adaptor (ScaB) scaffoldins were solved. The data revealed that group 1 Docs display a conserved mechanism of Coh recognition involving a single-binding mode. Therefore, in contrast to all cellulosomes described to date, the assembly of R. flavefaciens cellulosome involves single but not dual-binding mode Docs. Thus, this work reveals a novel mechanism of cellulosome assembly and challenges the ubiquitous implication of the dual-binding mode in the acquisition of cellulosome flexibility.

Journal Keywords: Bacteria; X-ray crystallography

Diamond Keywords: Bacteria; Enzymes

Subject Areas: Biology and Bio-materials, Chemistry


Instruments: I04-1-Macromolecular Crystallography (fixed wavelength)

Other Facilities: European Synchrotron Radiation Facility (ESRF)

Added On: 09/06/2017 10:22

Documents:
art%3A10.1038%2Fs41598-017-00919-w.pdf

Discipline Tags:

Biochemistry Chemistry Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)