Plant surfaces and interfaces: lignin, suberin and cutin
Abstract
As plants evolved from aquatic to terrestrial environment complex phenolic compounds (lignin, extractives) and natural polyesters (cutin, suberin) have played a major role by building hydrophobic surfaces and interfaces. Adaptation to survive in the great variety of habitats has resulted in quite diverse body plans. Tissues with distinct properties and functions are achieved by changing composition and structure at the different hierarchical levels (mm-μm-nm). Although general principles of the three compounds are known, they are the least understood plant polymers due to their high variability in amount and structure and unknown distribution and interaction on the micro- and nano-level as well as unsolved questions regarding polymerisation. We will bridge the knowledge gap on the microchemistry by Raman microspectroscopy (imaging) and elucidate nanostructure and -mechanics by Atomic force microscopy (AFM). Raman spectroscopy is based on the interaction of laser light with molecular vibrations, resulting in the energy of the laser photons being shifted up or down. The energy shift (Raman spectrum) gives information about the vibrational modes and thus molecular structure. In the Raman imaging approach plant samples cut with a microtome are scanned and different images calculated based on the thousands of Raman spectra acquired from the region of interest. These images represent chemical and structural information with a spatial resolution of ≈ 0.3µm (diffraction limit of the laser light) in context with plant anatomy. The same region will be scanned with a sharp tip using AFM to reveal the surface properties at nano-resolution. To drive the chemical information below the diffraction limit of the laser light both methods can be combined to the challenging tip-enhanced Raman spectroscopy (TERS) technique. With these sophisticated in-situ approaches we will 1) follow the lignification to tackle unsolved questions of lignin polymerisation, 2) reveal the chemistry and structure of tracheid and vessel walls on the micro- and nano-level and its implications on hydraulic and mechanical properties, 3) investigate the microchemistry and nanostructure of suberized and cutinized layers and their relation to barrier properties, 4) additionally assess the impact of water stress as drought is becoming more and more a limiting factor for tree growth. New insights into the micro and nano distribution and composition of the plant polymers and the impact of drought stress will be gained and important structure-function relationships revealed. This will break new scientific grounds in the field of plant physiology and wood science, will have an impact on optimised plant feedstock development (forestry, agriculture, breeding, genetic engineering) as well as utilisation (biorefinery, pulp and paper, biopolymers) and inspire new biomimetic approaches.
Publikationen
Revealing changes in molecular composition of plant cell walls on the micron-level by Raman mapping and vertex component analysis (VCA)
Autoren: Gierlinger, N Jahr: 2014
Journal articles
Elucidating structural and compositional changes in plant tissues and single cells by Raman spectroscopic imaging.
Autoren: Prats Mateu, B; Stefke, B; Hauser, M-T; Gierlinger, N Jahr: 2014
Journal articles
Imaging in-situ molecular structure of cells by Confocal Raman microscopy
Autoren: Gierlinger N Jahr: 2014
Conference & Workshop proceedings, paper, abstract
Studying in situ lignification in newly formed xylem cells by Confocal Raman microscopy
Autoren: Gierlinger N, Prats Mateau B, Stefke B, Burgert I Jahr: 2014
Conference & Workshop proceedings, paper, abstract
Chemistry and nano-structure of xylem: new insights and challenges by Raman imaging and Atomic force microscopy
Autoren: Gierlinger N Jahr: 2014
Conference & Workshop proceedings, paper, abstract
Project staff
Notburga Gierlinger
Assoc. Prof. Priv.-Doz. Mag. Dr. Notburga Gierlinger
burgi.gierlinger@boku.ac.at
Tel: +43 1 47654-80338
Project Leader
01.04.2014 - 31.03.2022
Martin Felhofer
Dr. Martin Felhofer B.Sc.
Project Staff
01.07.2015 - 31.08.2017
Project Staff
06.09.2017 - 28.03.2019
Project Staff
29.03.2019 - 01.05.2019
Oriane Danielle Chantal Morel
Oriane Danielle Chantal Morel MSc.
oriane.morel@boku.ac.at
Project Staff
01.10.2020 - 31.03.2022