title: The resistance of cellulases and xylanases to proteolytic inactivation.
abstract: The sensitivity of a range of cellulases and xylanases to proteolytic inactivation was investigated. The xylanases, all the Clostridium thermocellum cellulases and cellulase E from Pseudomonas fluorescens subsp. cellulosa exhibited no decrease in catalytic activity during a 3-h incubation with proteinases of the small intestine. Under these conditions, the control Escherichia coli enzymes analysed had half-lives of 4.3-13.5 min. The addition of substrate significantly decreased the sensitivity of proteinase-labile enzymes to inactivation. The significance of these data in relation to the use of cellulases and xylanases for improving animal nutrition is discussed.
authors.affiliation: Department of Biological and Nutritional Sciences, University of Newcastle upon Tyne, UK.
authors.forename: C M
authors.initials: CM
authors.lastname: Fontes
authors.forename: J
authors.initials: J
authors.lastname: Hall
authors.forename: B H
authors.initials: BH
authors.lastname: Hirst
authors.forename: G P
authors.initials: GP
authors.lastname: Hazlewood
authors.forename: H J
authors.initials: HJ
authors.lastname: Gilbert
mesh_terms: D002480:Cellulase / Q000378:metabolism*; D002918:Chymotrypsin / Q000494:pharmacology; D004386:Duodenum / Q000201:enzymology; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D010194:Pancreatin / Q000494:pharmacology; D043325:Xylan Endo-1,3-beta-Xylosidase; D014995:Xylosidases / Q000378:metabolism*
chemical_list: D010194:Pancreatin; D014995:Xylosidases; D043325:Xylan Endo-1,3-beta-Xylosidase; D002480:Cellulase; D002918:Chymotrypsin