Artigo Acesso aberto Produção Nacional Revisado por pares

Lignification in Sugarcane: Biochemical Characterization, Gene Discovery, and Expression Analysis in Two Genotypes Contrasting for Lignin Content

2013; Oxford University Press; Volume: 163; Issue: 4 Linguagem: Inglês

10.1104/pp.113.225250

ISSN

1532-2548

Autores

Alexandra Bottcher, Igor Cesarino, Adriana Brombini dos Santos, Renato Vicentini, Juliana Lischka Sampaio Mayer, Ruben Vanholme, Kris Morreel, Geert Goeminne, J. C. M. S. Moura, Paula Macedo Nóbile, Sandra Maria Carmello-Guerreiro, Ivan Antônio dos Anjos, Silvana Creste, Wout Boerjan, Marcos Guimarães de Andrade Landell, Paulo Mazzafera,

Tópico(s)

Lignin and Wood Chemistry

Resumo

Sugarcane (Saccharum spp.) is currently one of the most efficient crops in the production of first-generation biofuels. However, the bagasse represents an additional abundant lignocellulosic resource that has the potential to increase the ethanol production per plant. To achieve a more efficient conversion of bagasse into ethanol, a better understanding of the main factors affecting biomass recalcitrance is needed. Because several studies have shown a negative effect of lignin on saccharification yield, the characterization of lignin biosynthesis, structure, and deposition in sugarcane is an important goal. Here, we present, to our knowledge, the first systematic study of lignin deposition during sugarcane stem development, using histological, biochemical, and transcriptional data derived from two sugarcane genotypes with contrasting lignin contents. Lignin amount and composition were determined in rind (outer) and pith (inner) tissues throughout stem development. In addition, the phenolic metabolome was analyzed by ultra-high-performance liquid chromatography-mass spectrometry, which allowed the identification of 35 compounds related to the phenylpropanoid pathway and monolignol biosynthesis. Furthermore, the Sugarcane EST Database was extensively surveyed to identify lignin biosynthetic gene homologs, and the expression of all identified genes during stem development was determined by quantitative reverse transcription-polymerase chain reaction. Our data provide, to our knowledge, the first in-depth characterization of lignin biosynthesis in sugarcane and form the baseline for the rational metabolic engineering of sugarcane feedstock for bioenergy purposes.

Referência(s)