Chimeric cellulase matrix for investigating intramolecular synergism between non-hydrolytic disruptive functions of carbohydrate-binding modules and catalytic hydrolysis

J Biol Chem. 2012 Aug 24;287(35):29568-78. doi: 10.1074/jbc.M111.320358. Epub 2012 Jul 9.

Abstract

The conversion of renewable cellulosic biomass is of considerable interest for the production of biofuels and materials. The bottleneck in the efficient conversion is the compactness and resistance of crystalline cellulose. Carbohydrate-binding modules (CBMs), which disrupt crystalline cellulose via non-hydrolytic mechanisms, are expected to overcome this bottleneck. However, the lack of convenient methods for quantitative analysis of the disruptive functions of CBMs have hindered systematic studies and molecular modifications. Here we established a practical and systematic platform for quantifying and comparing the non-hydrolytic disruptive activities of CBMs via the synergism of CBMs and a catalytic module within designed chimeric cellulase molecules. Bioinformatics and computational biology were also used to provide a deeper understanding. A convenient vector was constructed to serve as a cellulase matrix into which heterologous CBM sequences can be easily inserted. The resulting chimeric cellulases were suitable for studying disruptive functions, and their activities quantitatively reflected the disruptive functions of CBMs on crystalline cellulose. In addition, this cellulase matrix can be used to construct novel chimeric cellulases with high hydrolytic activities toward crystalline cellulose.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Catalysis
  • Cellulase / chemistry*
  • Cellulase / genetics
  • Cellulase / metabolism*
  • Cellulose / chemistry*
  • Cellulose / metabolism*
  • Computational Biology
  • Gram-Negative Anaerobic Straight, Curved, and Helical Rods / enzymology*
  • Gram-Negative Anaerobic Straight, Curved, and Helical Rods / genetics
  • Hydrolysis
  • Molecular Sequence Data
  • Protein Binding
  • Protein Structure, Tertiary

Substances

  • Bacterial Proteins
  • Cellulose
  • Cellulase

Associated data

  • GENBANK/JN590045
  • GENBANK/JN590046
  • GENBANK/JN590047
  • GENBANK/JN590048
  • GENBANK/JN590049