Estudos iniciais de caracterização funcional de peroxidases e laccases potencialmente envolvidas no processo de lignificação em cana-de-açúcar / Initial studies on the functional characterization of peroxidases and laccases potentially involved in the lignification process in sugarcane

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

27/09/2012

RESUMO

Lignin is a complex heteropolymer deposited in the secondarily thickened walls of specialized plant cells to provide strength and rigidity for plants to stand upright and hydrophobicity to conducting cells for long-distance water transport. Although lignin is essential for plant growth and development, this phenolic polymer is the major plant cell wall component responsible for biomass recalcitrance and its presence negatively affects the use of ligriocellulose as a source for biofuels and bio-based materiais. Several evidences support the role of peroxidases and laccases in lignin polymerization. However, the identification and characterization of peroxidases/laccases involved in lignin polymerization is still a major bottleneck. Here, we carried out a comprehensive approach to identify candidate genes related to the combinatorial coupling of lignin monomers. ln chapter I, we analyzed the enzymatic activity and proteomic profile of class III peroxidases during sugarcane stem development. ln chapter II, suspension cell culture was used as a tool for the characterization of class III peroxidases potentially involved in lignin polymerization. Finally, in chapter III, we provide evidence for the role of a laccase gene in lignin biosynthesis in sugarcane, by using a combination of co-expression analysis, tissue-specific expression analysis and genetic complementation of an Arabidopsis thaliana mutant. To our knowledge, these are the first reports on the characterization of peroxidases and laccases in sugarcane, which might ultimately improve our understanding of the lignin metabolism in this important bioenergy crop.

ASSUNTO(S)

peroxidase lacase cana-de-açúcar lignina peroxidase laccase sugarcane lignin

Documentos Relacionados