Label-free in situ imaging of lignification in the cell wall of low lignin transgenic Populus trichocarpa

Schmidt, Martin; Schwartzberg, Adam M.; Perera, Pradeep N.; Weber‐Bargioni, Alexander; Carroll, Andrew; Sarkar, Purnamrita; Bosneaga, Elena; Urban, Jeffrey J.; Song, Jina; Balakshin, Mikhail; Capanema, Ewellyn A.; Auer, Manfred; Adams, Paul D.; Chiang, Vincent L.; Schuck, P. James

doi:10.1007/s00425-009-0963-x

Cited by 79 publications

(55 citation statements)

References 37 publications

(71 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The kinetic properties (Table III) and genetic functions of Ptr4CL3 (Schmidt et al, 2009) demonstrate that Ptr4CL3 is an ortholog of Pt4CL1 characterized previously (Hu et al, 1998(Hu et al, , 1999Harding et al, 2002). Orthologs of Ptr4CL3 have been identified and characterized for other Populus spp.…”

Section: Discussionmentioning

confidence: 61%

Monolignol Pathway 4-Coumaric Acid:Coenzyme A Ligases in Populus. trichocarpa: Novel Specificity, Metabolic Regulation, and Simulation of Coenzyme A Ligation Fluxes

et al. 2013

View full text Add to dashboard Cite

4-Coumaric acid:coenzyme A ligase (4CL) is involved in monolignol biosynthesis for lignification in plant cell walls. It ligates coenzyme A (CoA) with hydroxycinnamic acids, such as 4-coumaric and caffeic acids, into hydroxycinnamoyl-CoA thioesters. The ligation ensures the activated state of the acid for reduction into monolignols. In Populus spp., it has long been thought that one monolignol-specific 4CL is involved. Here, we present evidence of two monolignol 4CLs, Ptr4CL3 and Ptr4CL5, in Populus trichocarpa. Ptr4CL3 is the ortholog of the monolignol 4CL reported for many other species. Ptr4CL5 is novel. The two Ptr4CLs exhibited distinct Michaelis-Menten kinetic properties. Inhibition kinetics demonstrated that hydroxycinnamic acid substrates are also inhibitors of 4CL and suggested that Ptr4CL5 is an allosteric enzyme. Experimentally validated flux simulation, incorporating reaction/inhibition kinetics, suggested two CoA ligation paths in vivo: one through 4-coumaric acid and the other through caffeic acid. We previously showed that a membrane protein complex mediated the 3-hydroxylation of 4-coumaric acid to caffeic acid. The demonstration here of two ligation paths requiring these acids supports this 3-hydroxylation function. Ptr4CL3 regulates both CoA ligation paths with similar efficiencies, whereas Ptr4CL5 regulates primarily the caffeic acid path. Both paths can be inhibited by caffeic acid. The Ptr4CL5-catalyzed caffeic acid metabolism, therefore, may also act to mitigate the inhibition by caffeic acid to maintain a proper ligation flux. A high level of caffeic acid was detected in stemdifferentiating xylem of P. trichocarpa. Our results suggest that Ptr4CL5 and caffeic acid coordinately modulate the CoA ligation flux for monolignol biosynthesis.Lignin is an irreversible, terminal output of a major metabolic pathway in plant secondary metabolism. It is a polyphenolic structural component of the secondary cell walls of vascular plants and plays a unique role in the adaptation of plants to their environment and in resistance to biotic and abiotic stresses (Harada and Cote, 1985). In the formation of secondary cell walls, lignin is deposited between cells (middle lamella) and in cell walls. In the secondary wall, lignin surrounds the hemicelluloses and cellulose, forming a composite of the three major wall components (Timell, 1969;Terashima et al., 2009). Lignin is a major barrier to the utilization of biomass for energy, for papermaking, and for forage digestibility due to its interaction with cellulosics (Sarkanen, 1976;Chiang, 2002;Chen and Dixon, 2007). Studying lignin biosynthesis at the systems or holistic level should lead to better understanding of how the entire biosynthetic pathway is organized and regulated, providing more precise strategies to improve the production of energy, biomaterials, and food.Lignin is typically polymerized from three phenylpropanoid monomers, 4-coumaryl alcohol (metabolite 20 in Fig. 1), coniferyl alcohol (22), and sinapyl alcohol (24), also called the H, G, and S mo...

show abstract

Section: Discussionmentioning

confidence: 61%

Monolignol Pathway 4-Coumaric Acid:Coenzyme A Ligases in Populus. trichocarpa: Novel Specificity, Metabolic Regulation, and Simulation of Coenzyme A Ligation Fluxes

et al. 2013

View full text Add to dashboard Cite

show abstract

“…Raman signatures of the phenolic monolignols will be registered at 1,600 cm −1 (aromatic), the carbonyl and unsaturated carbon double bonds at 1,735 cm −1 and 1,650 cm −1 , respectively. Thus, chemical imaging by confocal Raman microscopy was used for the spatial distribution of cellulose and lignin in wood walls in situ [160]. A review by Agarwal [159] summarizes the use of Raman spectroscopy for plant cell imaging.…”

Section: Raman Spectroscopymentioning

confidence: 99%

Supramolecular Self-Assembled Chaos: Polyphenolic Lignin’s Barrier to Cost-Effective Lignocellulosic Biofuels

et al. 2010

View full text Add to dashboard Cite

Phenylpropanoid metabolism yields a mixture of monolignols that undergo chaotic, non-enzymatic reactions such as free radical polymerization and spontaneous selfassembly in order to form the polyphenolic lignin which is a barrier to cost-effective lignocellulosic biofuels. Post-synthesis lignin integration into the plant cell wall is unclear, including how the hydrophobic lignin incorporates into the wall in an initially hydrophilic milieu. Self-assembly, self-organization and aggregation give rise to a complex, 3D network of lignin that displays randomly branched topology and fractal properties. Attempts at isolating lignin, analogous to archaeology, are instantly destructive and nonrepresentative of in planta. Lack of plant ligninases or enzymes that hydrolyze specific bonds in lignin-carbohydrate complexes (LCCs) also frustrate a better grasp of lignin. Supramolecular self-assembly, nano-mechanical properties of lignin-lignin, ligninpolysaccharide interactions and association-dissociation kinetics affect biomass deconstruction and thereby cost-effective biofuels production. OPEN ACCESSMolecules 2010, 15 8642

show abstract

“…), beech (Fagus sylvatica) and oak (Quercus robur) (Lehringer et al 2008). Schmidt et al (2009) studied the lignification in wild-type and lignin-reduced 4CL transgenic Populus trichocarpa stem wood and showed that transgenic reduction of lignin is particularly pronounced in the S2 wall layer of fibres .…”

Section: Uv-vis Spectra Of Lignin and Other Ring Structuresmentioning

confidence: 99%

Microspectroscopy as applied to the study of wood molecular structure

Fackler

Thygesen

2012

Wood Sci Technol

View full text Add to dashboard Cite

Microspectroscopy gives access to spatially resolved information on the molecular structure and chemical composition of a material. For a highly heterogeneous and anisotropic material like wood, such information is essential when assessing structure/property relationships such as moisture-induced dimensional changes, decay resistance or mechanical properties. It is, however, important to choose the right technique for the purpose at hand and to apply it in a suitable way if any new insights are to be gained. This review presents and compares three different microspectroscopic techniques: infrared, Raman and ultraviolet. Issues such as sample preparation, spatial resolution, data acquisition and extraction of knowledge from the spectral data are discussed. Additionally, an overview of applications in wood science is given for each method. Lastly, current trends and challenges within microspectroscopy of wood are discussed.

show abstract

Label-free in situ imaging of lignification in the cell wall of low lignin transgenic Populus trichocarpa

Cited by 79 publications

References 37 publications

Monolignol Pathway 4-Coumaric Acid:Coenzyme A Ligases in Populus. trichocarpa: Novel Specificity, Metabolic Regulation, and Simulation of Coenzyme A Ligation Fluxes

Monolignol Pathway 4-Coumaric Acid:Coenzyme A Ligases in Populus. trichocarpa: Novel Specificity, Metabolic Regulation, and Simulation of Coenzyme A Ligation Fluxes

Supramolecular Self-Assembled Chaos: Polyphenolic Lignin’s Barrier to Cost-Effective Lignocellulosic Biofuels

Microspectroscopy as applied to the study of wood molecular structure

Contact Info

Product

Resources

About