title: Strategies for the production of cell wall-deconstructing enzymes in lignocellulosic biomass and their utilization for biofuel production.
abstract: Microbial cell wall-deconstructing enzymes are widely used in the food, wine, pulp and paper, textile, and detergent industries and will be heavily utilized by cellulosic biorefineries in the production of fuels and chemicals. Due to their ability to use freely available solar energy, genetically engineered bioenergy crops provide an attractive alternative to microbial bioreactors for the production of cell wall-deconstructing enzymes. This review article summarizes the efforts made within the last decade on the production of cell wall-deconstructing enzymes in planta for use in the deconstruction of lignocellulosic biomass. A number of strategies have been employed to increase enzyme yields and limit negative impacts on plant growth and development including targeting heterologous enzymes into specific subcellular compartments using signal peptides, using tissue-specific or inducible promoters to limit the expression of enzymes to certain portions of the plant or certain times, and fusion of amplification sequences upstream of the coding region to enhance expression. We also summarize methods that have been used to access and maintain activity of plant-generated enzymes when used in conjunction with thermochemical pretreatments for the production of lignocellulosic biofuels.
authors.affiliation: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA.
authors.forename: Sang-Hyuck
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, MI, USA.|Department of Chemical Engineering, Michigan Technological University, Houghton, MI, USA.
authors.forename: Rebecca Garlock
authors.identifier: 0000-0001-5020-646X
authors.initials: RG
authors.lastname: Ong
authors.affiliation: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA.
authors.forename: Mariam
authors.initials: M
authors.lastname: Sticklen
mesh_terms: D001419:Bacteria / Q000201:enzymology; D056804:Biofuels; D018533:Biomass; D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism*; D003246:Conservation of Energy Resources; D008031:Lignin / Q000737:chemistry*; D060847:Metabolic Engineering / Q000379:methods*; D030821:Plants, Genetically Modified / Q000166:cytology; D021382:Protein Sorting Signals; D011506:Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D056804:Biofuels; D021382:Protein Sorting Signals; D011506:Proteins; C036909:lignocellulose; D008031:Lignin
keywords: biofuels; cell wall-deconstructing enzymes; lignocellulosic biomass; plant subcellular compartments; promoter; signal peptides