Dataset Information

A dynamic model of lignin biosynthesis in Brachypodium distachyon.

ABSTRACT:

Background

Lignin is a crucial molecule for terrestrial plants, as it offers structural support and permits the transport of water over long distances. The hardness of lignin reduces plant digestibility by cattle and sheep; it also makes inedible plant materials recalcitrant toward the enzymatic fermentation of cellulose, which is a potentially valuable substrate for sustainable biofuels. Targeted attempts to change the amount or composition of lignin in relevant plant species have been hampered by the fact that the lignin biosynthetic pathway is difficult to understand, because it uses several enzymes for the same substrates, is regulated in an ill-characterized manner, may operate in different locations within cells, and contains metabolic channels, which the plant may use to funnel initial substrates into specific monolignols.

Results

We propose a dynamic mathematical model that integrates various datasets and other information regarding the lignin pathway in Brachypodium distachyon and permits explanations for some counterintuitive observations. The model predicts the lignin composition and label distribution in a BdPTAL knockdown strain, with results that are quite similar to experimental data.

Conclusion

Given the present scarcity of available data, the model resulting from our analysis is presumably not final. However, it offers proof of concept for how one may design integrative pathway models of this type, which are necessary tools for predicting the consequences of genomic or other alterations toward plants with lignin features that are more desirable than in their wild-type counterparts.

SUBMITTER: Faraji M

PROVIDER: S-EPMC6145374 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

A dynamic model of lignin biosynthesis in <i>Brachypodium distachyon</i>.

Faraji Mojdeh M Fonseca Luis L LL Escamilla-Treviño Luis L Barros-Rios Jaime J Engle Nancy L NL Yang Zamin K ZK Tschaplinski Timothy J TJ Dixon Richard A RA Voit Eberhard O EO

Biotechnology for biofuels 20180919

<h4>Background</h4>Lignin is a crucial molecule for terrestrial plants, as it offers structural support and permits the transport of water over long distances. The hardness of lignin reduces plant digestibility by cattle and sheep; it also makes inedible plant materials recalcitrant toward the enzymatic fermentation of cellulose, which is a potentially valuable substrate for sustainable biofuels. Targeted attempts to change the amount or composition of lignin in relevant plant species have been ...[more]

PMID: 30250505

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