Hydrophobic Layers Attached to Cell Walls. Cutin, Suberin and Associated Waxes

The polysaccharidic cell walls do not constitute a significant diffusion barrier, and, therefore, plants attach a hydrophobic layer to the wall to erect such a barrier. Such diffusion barriers consist of an insoluble polymeric structural component and a complex mixture of extractable lipids, collectively called wax. We shall briefly summarize the general characteristics, structure, composition, metabolism, and function of the waxes and the polymeric materials. Other more detailed reviews on the subject are available (Martin and Juniper 1970, Kolattukudy 1980b) and the function of the components is discussed by J. Schonherr, Chapter 1.6, in Volume 12B of this series.