title: Preferential adsorption and activity of monocomponent cellulases on lignocellulose thin films with varying lignin content.
abstract: Understanding the enzymatic hydrolysis of cellulose and the influence of lignin in the process are critical for viable production of fuels and chemicals from lignocellulosic biomass. The interactions of monocomponent cellulases with cellulose and lignin substrates were investigated by using thin films supported on quartz crystal microgravimetry (QCM) resonators. Trichoderma reesei exoglucanase (CBH-I) and endoglucanase (EG-I) bound strongly to both cellulose and lignin but EG-I exhibited a distinctive higher affinity with lignin, causing a more extensive inhibition of the cellulolytic reactions. CBH-I was found to penetrate into the bulk of the cellulose substrate increasing the extent of hydrolysis and film deconstruction. In the absence of a cellulose binding domain (CBD) and a linker, the CBH-I core adsorbed slowly and was not able to penetrate into the film. Conversely to CBH-I, EG-I exhibited activity only on the surface of the lignocellulose substrate even when containing a CBD and a linker. Interestingly, EG-I displayed a clearly different interaction profile as a function of contact time registered by QCM.
authors.affiliation: Department of Forest Products Technology, School of Chemical Technology, Aalto University, FI-00076 Aalto, Espoo, Finland. martin.raquel@inia.es
authors.forename: Raquel
authors.initials: R
authors.lastname: Martín-Sampedro
authors.forename: Jenni L
authors.initials: JL
authors.lastname: Rahikainen
authors.forename: Leena-Sisko
authors.initials: LS
authors.lastname: Johansson
authors.forename: Kaisa
authors.initials: K
authors.lastname: Marjamaa
authors.forename: Janne
authors.initials: J
authors.lastname: Laine
authors.forename: Kristiina
authors.initials: K
authors.lastname: Kruus
authors.forename: Orlando J
authors.initials: OJ
authors.lastname: Rojas
mesh_terms: D000327:Adsorption; D044602:Cellulases / Q000737:chemistry / Q000378:metabolism*; D043366:Cellulose 1,4-beta-Cellobiosidase / Q000737:chemistry* / Q000378:metabolism*; D006868:Hydrolysis; D008031:Lignin / Q000032:analysis / Q000737:chemistry*; D014242:Trichoderma / Q000201:enzymology / Q000378:metabolism
chemical_list: C036909:lignocellulose; D008031:Lignin; D044602:Cellulases; D043366:Cellulose 1,4-beta-Cellobiosidase