title: [Kinetics of xylanase and cellulase production by Ascobolus gamundii (Fungi, Ascomycotina)].
abstract: Growth and cellulase-xylanase enzyme systems production by Ascobolus gamundii were evaluated in synthetic media with or without natural inducers. The basal level of enzyme complexes was determined using glucose as carbon source. With crystalline cellulose, the amount of endoglucanase and beta-glucosidase was 2-4 times the basal, and the level of endoxylanase and beta-xylosidase was 3 times higher than that observed with glucose. When using xylan as carbon source, endoxylanase and endoglucanase were induced. The higher production of the enzyme systems was observed during the log-phase growth of A. gamundii with a mixture of cellulose and xylan as carbon source. The generalized induction of both enzyme complexes could be due to evolutive adaptation to the substrate (herbivore dung) in which cellulose and hemicellulose are associated to conform the plants cell-walls.
authors.affiliation: Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
authors.forename: A S
authors.initials: AS
authors.lastname: Sivori
authors.forename: O A
authors.initials: OA
authors.lastname: Mercuri
authors.forename: F
authors.initials: F
authors.lastname: Forchiassin
mesh_terms: D001203:Ascomycota / Q000201:enzymology* / Q000235:genetics; D002480:Cellulase / Q000096:biosynthesis* / Q000235:genetics; D002482:Cellulose / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases; D004790:Enzyme Induction; D005243:Feces / Q000382:microbiology; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005947:Glucose / Q000378:metabolism; D007700:Kinetics; D043325:Xylan Endo-1,3-beta-Xylosidase; D014990:Xylans / Q000378:metabolism; D014995:Xylosidases / Q000096:biosynthesis* / Q000235:genetics; D001617:beta-Glucosidase / Q000096:biosynthesis / Q000235:genetics
chemical_list: D005656:Fungal Proteins; D014990:Xylans; D002482:Cellulose; D014995:Xylosidases; D001617:beta-Glucosidase; D043325:Xylan Endo-1,3-beta-Xylosidase; C026579:exo-1,4-beta-D-xylosidase; D002480:Cellulase; D043364:Endo-1,4-beta Xylanases; D005947:Glucose