title: Production of Glucaric Acid from Hemicellulose Substrate by Rosettasome Enzyme Assemblies.
abstract: Hemicellulose biomass is a complex polymer with many different chemical constituents that can be utilized as industrial feedstocks. These molecules can be released from the polymer and transformed into value-added chemicals through multistep enzymatic pathways. Some bacteria produce cellulosomes which are assemblies composed of lignocellulolytic enzymes tethered to a large protein scaffold. Rosettasomes are artificial engineered ring scaffolds designed to mimic the bacterial cellulosome. Both cellulosomes and rosettasomes have been shown to facilitate much higher rates of biomass hydrolysis compared to the same enzymes free in solution. We investigated whether tethering enzymes involved in both biomass hydrolysis and oxidative transformation to glucaric acid onto a rosettasome scaffold would result in an analogous production enhancement in a combined hydrolysis and bioconversion metabolic pathway. Three different enzymes were used to hydrolyze birchwood hemicellulose and convert the substituents to glucaric acid, a top-12 DOE value added chemical feedstock derived from biomass. It was demonstrated that colocalizing the three different enzymes to the synthetic scaffold resulted in up to 40 % higher levels of product compared to uncomplexed enzymes.
authors.affiliation: Bioproducts Research Unit, USDA-ARS-WRRC, 800 Buchanan St., Albany, CA, 94710, USA. Charles.Lee@ars.usda.gov.
authors.forename: Charles C
authors.initials: CC
authors.lastname: Lee
authors.affiliation: Bioproducts Research Unit, USDA-ARS-WRRC, 800 Buchanan St., Albany, CA, 94710, USA.
authors.forename: Rena E
authors.initials: RE
authors.lastname: Kibblewhite
authors.affiliation: NASA Ames Research Center, Moffett Field, CA, 94035, USA.
authors.forename: Chad D
authors.initials: CD
authors.lastname: Paavola
authors.affiliation: Bioproducts Research Unit, USDA-ARS-WRRC, 800 Buchanan St., Albany, CA, 94710, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Orts
authors.affiliation: Bioproducts Research Unit, USDA-ARS-WRRC, 800 Buchanan St., Albany, CA, 94710, USA.
authors.forename: Kurt
authors.initials: K
authors.lastname: Wagschal
mesh_terms: D001419:Bacteria / Q000737:chemistry / Q000201:enzymology; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001674:Bioelectric Energy Sources; D044603:Cellulosomes / Q000737:chemistry / Q000201:enzymology*; D005818:Genetic Engineering; D005937:Glucaric Acid / Q000138:chemical synthesis* / Q000737:chemistry; D006868:Hydrolysis; D015394:Molecular Structure; D009097:Multienzyme Complexes / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D009097:Multienzyme Complexes; D011134:Polysaccharides; C007916:hemicellulose; D005937:Glucaric Acid
keywords: Enzyme nanoassembly; Glucaric acid; Hemicellulose; Lignocellulases