Detoxification of “alpeorujo” by Coriolopsis rigida: Role of lac1 gene in the process and its transcriptional regulation

JURADO, M.; SAPARRAT M. C. N.; DÍAZ, R.; MARTÍNEZ, M. J.

Reims, Francia.

Simposio; Lignobiotech One Symposium”. Reims, Francia.; 2010

Bernard Kurek, INRA, France

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:595.3pt 841.9pt; margin:70.85pt 85.05pt 70.85pt 85.05pt; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The white-rot fungus Coriolopsis rigida is being extensively studied for its outstanding ability to degrade lignin and other phenolic aromatic compounds causing environmental problems. Laccase is the unique ligninolytic enzyme secreted by the fungus under a different range of culture conditions assayed. In this work we study the role of laccase in detoxification of the water soluble fraction of ‘alpeorujo’ (WSFA), a solid by-product derived from the use of the two-phase system for olive oil extraction, containing high levels of phenols which limit its use as fertilizer and/or amendment. We also evaluate the effect of copper supplementation and WSFA concentration on phenol reduction, as well as its impact on the survival of Azospirillum brasiliense, a N2 fixing soil-rhizobacterium promoting the plant growth. Finally, we report the purification of laccase involved in phenol reduction, and the isolation of the laccase gene lcc1, whose transcriptional response under different chemical agents is also evaluated.