title: Interactions of endoglucanases with amorphous cellulose films resolved by neutron reflectometry and quartz crystal microbalance with dissipation monitoring.
abstract: A study of the interaction of four endoglucanases with amorphous cellulose films by neutron reflectometry (NR) and quartz crystal microbalance with dissipation monitoring (QCM-D) is reported. The endoglucanases include a mesophilic fungal endoglucanase (Cel45A from H. insolens), a processive endoglucanase from a marine bacterium (Cel5H from S. degradans ), and two from thermophilic bacteria (Cel9A from A. acidocaldarius and Cel5A from T. maritima ). The use of amorphous cellulose is motivated by the promise of ionic liquid pretreatment as a second generation technology that disrupts the native crystalline structure of cellulose. The endoglucanases displayed highly diverse behavior. Cel45A and Cel5H, which possess carbohydrate-binding modules (CBMs), penetrated and digested within the bulk of the films to a far greater extent than Cel9A and Cel5A, which lack CBMs. While both Cel45A and Cel5H were active within the bulk of the films, striking differences were observed. With Cel45A, substantial film expansion and interfacial broadening were observed, whereas for Cel5H the film thickness decreased with little interfacial broadening. These results are consistent with Cel45A digesting within the interior of cellulose chains as a classic endoglucanase, and Cel5H digesting predominantly at chain ends consistent with its designation as a processive endoglucanase.
authors.affiliation: Joint BioEnergy Institute, Emeryville, California, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Cheng
authors.forename: Supratim
authors.initials: S
authors.lastname: Datta
authors.forename: Zelin
authors.initials: Z
authors.lastname: Liu
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Jaclyn K
authors.initials: JK
authors.lastname: Murton
authors.forename: Page A
authors.initials: PA
authors.lastname: Brown
authors.forename: Michael S
authors.initials: MS
authors.lastname: Jablin
authors.forename: Manish
authors.initials: M
authors.lastname: Dubey
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Majewski
authors.forename: Candice E
authors.initials: CE
authors.lastname: Halbert
authors.forename: James F
authors.initials: JF
authors.lastname: Browning
authors.forename: Alan R
authors.initials: AR
authors.lastname: Esker
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Watson
authors.forename: Haito
authors.initials: H
authors.lastname: Zhang
authors.forename: Steven W
authors.initials: SW
authors.lastname: Hutcheson
authors.forename: Dale L
authors.initials: DL
authors.lastname: Huber
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: Sale
authors.forename: Blake A
authors.initials: BA
authors.lastname: Simmons
authors.forename: Michael S
authors.initials: MS
authors.lastname: Kent
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D002480:Cellulase / Q000737:chemistry* / Q000378:metabolism; D002482:Cellulose / Q000737:chemistry* / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D052578:Ionic Liquids / Q000737:chemistry; D033363:Neutron Diffraction; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties
chemical_list: D001426:Bacterial Proteins; D005656:Fungal Proteins; D052578:Ionic Liquids; D002482:Cellulose; D002480:Cellulase