Asymmetric water transport in dense leaf cuticles and cuticle-inspired compositionally graded membranes

• Published in: Nature communications 2021-02, Vol.12 (1), p.1267-11, Article 1267
• Main Authors: Kamtsikakis, Aristotelis, Baales, Johanna, Zeisler-Diehl, Viktoria V., Vanhecke, Dimitri, Zoppe, Justin O., Schreiber, Lukas, Weder, Christoph
• Format: Article
• Language: English
• Subjects: 101/28; 140/133; 147/28; 631/449/1736; 631/449/2668; 639/301/357; Asymmetry; Biological Transport - genetics; Biological Transport - physiology; Biomimetics; Cell walls; Cellulose; Cuticles; Cutin; Flowers & plants; Humanities and Social Sciences; Hydrophobicity; Leaves; Membrane Lipids - metabolism; Membranes; multidisciplinary; Nanocomposites; Nanocomposites - chemistry; Nanocrystals; Nanoparticles - chemistry; Organs; Plant cuticle; Plant Epidermis - metabolism; Plant Leaves - metabolism; Plants; Polarity; Polymers; Polysaccharides; Saccharides; Science; Science (multidisciplinary); Transpiration; Water - metabolism; Water loss; Water transport; Waxes - metabolism
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-21500-0

Most of the aerial organs of vascular plants are covered by a protective layer known as the cuticle, the main purpose of which is to limit transpirational water loss. Cuticles consist of an amphiphilic polyester matrix, polar polysaccharides that extend from the underlying epidermal cell wall and become less prominent towards the exterior, and hydrophobic waxes that dominate the surface. Here we report that the polarity gradient caused by this architecture renders the transport of water through astomatous olive and ivy leaf cuticles directional and that the permeation is regulated by the hydration level of the cutin-rich outer cuticular layer. We further report artificial nanocomposite membranes that are inspired by the cuticles’ compositionally graded architecture and consist of hydrophilic cellulose nanocrystals and a hydrophobic polymer. The structure and composition of these cuticle-inspired membranes can easily be varied and this enables a systematic investigation of the water transport mechanism. Most aerial organs of vascular plants are covered by a waxy cuticle that limits water loss. Here the authors show that the asymmetric architecture of the cuticle creates a polarity gradient to ensure directional movement of water through olive and ivy leaf cuticles and construct bioinspired artificial membranes that mimic cuticle behaviour.