title: Diffusional and transcriptional mechanisms involved in laccases production by Pleurotus ostreatus CP50.
abstract: The independent effects of hydrodynamic stress (assessed as the Energy Dissipation/Circulation Function, EDCF) and dissolved oxygen tension (DOT) on the growth, morphology and laccase production by Pleurotus ostreatus CP50 were studied using a 3(2) factorial design in a 10L reactor. A bell-shape function for fungus growth between 8 and 22% DOT was observed, as well as a significant negative effect on laccase production and the expression of poxc, the gene encoding for the most abundant laccase produced by P. ostreatus CP50. Increasing EDCF from 1 to 21 kW/m(3)s, had a positive effect on fungus growth, whereas no effect on poxc gene expression was observed. However, the increase in EDCF favored the specific laccase production due to the generation of smaller pellets with less diffusional limitations and increased metabolically active biomass. The results show, for the first time, that hydrodynamic effects on growth and laccase production are mainly physical and diffusional, while the influence of the dissolved oxygen is at transcriptional level.
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México.
authors.forename: Karen I
authors.initials: KI
authors.lastname: Fernández-Alejandre
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México.
authors.forename: Noemí
authors.initials: N
authors.lastname: Flores
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México.
authors.forename: Raunel
authors.initials: R
authors.lastname: Tinoco-Valencia
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México.
authors.forename: Mario
authors.initials: M
authors.lastname: Caro
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México.
authors.forename: Celia
authors.initials: C
authors.lastname: Flores
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México.
authors.forename: Enrique
authors.initials: E
authors.lastname: Galindo
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210 Cuernavaca, Morelos, México. Electronic address: leobardo@ibt.unam.mx.
authors.forename: Leobardo
authors.initials: L
authors.lastname: Serrano-Carreón
mesh_terms: D018533:Biomass; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D057446:Hydrodynamics; D042845:Laccase / Q000235:genetics* / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D020076:Pleurotus / Q000201:enzymology / Q000254:growth & development*; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D042845:Laccase; D010100:Oxygen
keywords: Dissolved oxygen; Gene expression; Hydrodynamics; Laccases; Pleurotus ostreatus.