Institute:
University of Santiago de Compostela (USC),
Group of Environmental Engineering and Bioprocesses (GEEB)
Address:
Rúa Lope Gómez de Marzoa
15782 Santiago de Compostela
Phone: +34 981 563100
Fax: +34 981 528050
Project leader:
Prof. Maite Teresa Moreira (tmoreira(at)usc.es)
Responsible co-worker:
Thelmo A. Lu Chau, Ph.D.
Objectives:
Ligninolytic fungi are responsible of the conversion of lignocellulosic material in nature. For this purpose white-rot fungi (wrf) produce ligninolytic enzymes that act extracellular to degrade lignin. These enzymes include laccases, lignin- (LiP) and manganese peroxidases (MnP). It has been demonstrated that wrf, as well as their ligninolytic systems, acting in vivo and in vitro, are able to degrade a wide range of complex substrates. However, not all the ligninolytic enzymes are produced in large quantities. Currently, only laccase is commercially available, while many attempts to overproduce MnP and LiP has not been so successful.
A ligninolytic enzyme that can degrade substrates typically oxidized by both LiP and MnP has been reported in Pleurotus and Bjerkandera species. This versatile peroxidase (VP) has the capacity to act also without manganese, like a LiP enzyme. Although many attempts have been conducted to overproduce this VP enzyme, the titers of active enzyme achieved have been low considering its potential use. Before considering this ligninolytic enzyme for a large scale application the increase of the enzyme levels through the optimization of operational conditions, as well as its scale-up from small flasks to semi-pilot bioreactors should be conducted.
In this project it is proposed to evaluate the production potential capacity, as well as the enzymatic characteristics of the VP produced by a new isolated wrf (anamorph of B. adusta) in comparison to the more studied P. eryngii and B. adusta fungi. The USC group will be in charge of the development of lignin modifying enzymes (manganese and/or versatile peroxidases) with a high activity towards the production of phenoxy radicals by partial lignin activation.
To conquer this objective, USC will carry out the evaluation of ligninolytic activities obtained from three fungal strains, the enzymatic and kinetic characterization of the selected ligninolytic enzyme, the optimization of the culture operational conditions for the production of the enzyme and the scale-up of the fermentation process and the production of large quantities of enzyme for its application in the modification of biopolymers and composites.
