title: Regulation of xylanase in Aspergillus phoenicis: a physiological and molecular approach.
abstract: Microbial xylanolytic enzymes have a promising biotechnological potential, and are extensively applied in industries. In this study, induction of xylanolytic activity was examined in Aspergillus phoenicis. Xylanase activity induced by xylan, xylose or beta-methylxyloside was predominantly extracellular (93-97%). Addition of 1% glucose to media supplemented with xylan or xylose repressed xylanase production. Glucose repression was alleviated by addition of cAMP or dibutyryl-cAMP. These physiological observations were supported by a Northern analysis using part of the xylanase gene ApXLN as a probe. Gene transcription was shown to be induced by xylan, xylose, and beta-methylxyloside, and was repressed by the addition of 1% glucose. Glucose repression was partially relieved by addition of cAMP or dibutyryl cAMP.
authors.affiliation: Departamento de Biologia da Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, SP 14040-901, Brazil.
authors.forename: Ana Carolina Segato
authors.initials: AC
authors.lastname: Rizzatti
authors.forename: Fernanda Zanolli
authors.initials: FZ
authors.lastname: Freitas
authors.forename: Maria Célia
authors.initials: MC
authors.lastname: Bertolini
authors.forename: Simone Carvalho
authors.initials: SC
authors.lastname: Peixoto-Nogueira
authors.forename: Héctor Francisco
authors.initials: HF
authors.lastname: Terenzi
authors.forename: João Atílio
authors.initials: JA
authors.lastname: Jorge
authors.forename: Maria de Lourdes Teixeira de Moraes
authors.initials: Mde L
authors.lastname: Polizeli
mesh_terms: D000595:Amino Acid Sequence; D001230:Aspergillus / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D000242:Cyclic AMP / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D000242:Cyclic AMP; D043364:Endo-1,4-beta Xylanases