A preliminary evaluation of transcriptional gene expression in Aspergillus niger ATCC 10864 biofilms developed on polyester cloth was carried out. The expression analysis of genes encoding some lignocellulolytic enzymes and some regulatory genes by means of RT-PCR showed that eng1, eglC, exo, eglA, eglB and xynB genes are differentially expressed in biofilm fermentation either time-related or through the production of more than a transcript as compared to A. niger grown in submerged fermentation. Likewise, the regulatory genes xlnR and creA showed time-related expression patterns that were different in both fermentation systems. Results attained in this work contribute with an initial molecular evidence of differential gene expression as well as differential gene regulation patterns in fungal biofilms that may be related to cell adhesion.

Se realizó una evaluación génica preliminar a nivel transcripcional de biopelículas de Aspergillus niger ATCC 10864 desarrolladas sobre poliéster respecto a algunas enzimas lignocelulolíticas. El análisis de expresión de genes de enzimas lignocelulolíticas y genes reguladores mediante RT-PCR mostró que los genes eng1, eglC, exo y eglA, eglB y xynB son diferencialmente expresados ya sea temporalmente o mediante más de un transcripto en comparación con cultivos sumergidos. Asimismo, los genes reguladores xlnR y creA mostraron patrones temporales de expresión distintos en ambos sistemas. Los resultados obtenidos aportan la evidencia molecular inicial de expresión diferencial de genes en biopelículas así como patrones de regulación diferencial muy probablemente ligada a la adhesión celular.

This work was supported by INCAGRO (Ministry of Agriculture, Peru) and CONCYTEC (Ministry of Education, Peru). The authors wish to thank CERTINTEX (Lima, Peru) for the use of its SEM facilities, and Mr. Gianangelo Nava (CERTINTEX) for his SEM technical assistance.