title: Effect of textile dyes on activity and differential regulation of laccase genes from Pleurotus ostreatus grown in submerged fermentation.
abstract: This research was conducted to extend the knowledge on the differential regulation of laccase genes in response to dyes. In order to accomplish this, we analyzed both, the expression of five laccase genes by real time RT-qPCR, and also the laccase activity and isoforms patterns during the time-course of a Pleurotus ostreatus submerged fermentation supplemented with either acetyl yellow G (AYG) or remazol brilliant blue R (RBBR) dyes. For the purpose of obtaining a stable reference gene for optimal normalization of RT-quantitative PCR gene expression assays, we tested four candidate reference genes. As a result of this analysis, gpd was selected as reference index for data normalization. The addition of dyes had an induction effect on the enzymatic activity and also modified the zymogram profile. Fermentation with RBBR showed the highest laccase activity and number of isoforms along the course of the fermentation. Laccase gene expression profiles displayed up/down regulation along the fermentation time in four laccase genes (pox4, pox3, poxa1b and pox2), while pox1 was not expressed in either of the fermentation conditions. AYG addition caused the highest induction and repression levels for genes pox3 and poxa1b respectively. The expression level for all genes in the presence of RBBR were lower than in AYG, being in both conditions this response growth time dependent. These results show the influence of the nature of dyes on the induction level of laccase activity and on the differential regulation of the laccase genes expression in P. ostreatus.
authors.affiliation: Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Carretera Estatal Sta Inés Tecuexcomac-Tepetitla, km. 1.5, C.P: 90700, Tepetitla de Lárdizabal, Tlaxcala, Mexico.
authors.forename: Verónica
authors.initials: V
authors.lastname: Garrido-Bazán
authors.affiliation: Centro de Investigaciones Biológicas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico.
authors.forename: Maura
authors.initials: M
authors.lastname: Téllez-Téllez
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Cinvestav, Irapuato, Gto, Mexico.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Herrera-Estrella
authors.affiliation: Laboratory of Biotechnology, Research Center for Biological Sciences, Universidad Autónoma de Tlaxcala, Tlaxcala, Mexico.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Díaz-Godínez
authors.affiliation: Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Carretera Estatal Sta Inés Tecuexcomac-Tepetitla, km. 1.5, C.P: 90700, Tepetitla de Lárdizabal, Tlaxcala, Mexico.
authors.forename: Soley
authors.initials: S
authors.lastname: Nava-Galicia
authors.affiliation: Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Carretera Estatal Sta Inés Tecuexcomac-Tepetitla, km. 1.5, C.P: 90700, Tepetitla de Lárdizabal, Tlaxcala, Mexico.
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Villalobos-López
authors.affiliation: Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Carretera Estatal Sta Inés Tecuexcomac-Tepetitla, km. 1.5, C.P: 90700, Tepetitla de Lárdizabal, Tlaxcala, Mexico.
authors.forename: Analilia
authors.initials: A
authors.lastname: Arroyo-Becerra
authors.affiliation: Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Carretera Estatal Sta Inés Tecuexcomac-Tepetitla, km. 1.5, C.P: 90700, Tepetitla de Lárdizabal, Tlaxcala, Mexico. mbibbinsm@ipn.mx.
authors.forename: Martha
authors.initials: M
authors.lastname: Bibbins-Martínez
keywords: Gene expression; Isoenzymes; Laccases; Pleurotus ostreatus; RT-qPCR