ARTICLE

LIGNOFIBRILS ON THE EXTERNAL CELL WALL SURFACE OF CULTURED PLANT CELLS

¹ From the Biochemistry Laboratory and the Division of Biology, National Research Council of Canada, Ottawa, and the Département de Biologie, Université Laval, Québec, P. Q., Canada

Small strands and bundles of strands extend from the outside surface of suspension-cultured cells of Daucus, Ipomoea, and Phaseolus into the medium. This fibrous cell coat is present in all samples from various growth stages but appears to increase in quantity in the order Ipomoea < Phaseolus < Daucus. The bundles are often many microns in length and display great variation in frequency, size, and form. Identification of the composition of the strands and bundles as lignin is consistent with the following observations: alkaline nitrobenzene oxidation of the strands to compounds which resemble monomers of wood lignin; resistance of the strands to pronase, trypsin, pectinase, and lipase; strong irreversible adsorption of heavy metals; deposition of silver granules by treatment with silver nitrate-hexamine reagent; extraction of the bundles with aqueous dioxane (Björkman procedure); presence in quantity of a structured form of Klason lignin; and existence of material giving a positive test with the Wiesner reagent. Large individual strands (lignofibrils) from Phaseolus show the form of a flat ribbon with very thin branches at irregular intervals. This form does not vary with preparatory techniques, although its electron opacity does. Intercellular spaces display considerable structure and sometimes contain sheets of fibrillar material merging with both the middle lamella between the cells and the surface bundles facing the medium. These sheets are probably another form of association of the lignofibrils. It is suggested that natural fibrous lignin may be a much commoner component of plant tissue than suspected hitherto.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

• Askanas, V., Engel, W. K., Reddy, N. B., Barth, P. G., Bethlem, J., Krauss, D. R., Hibberd, M. E., Lawrence, J. V., Carter, L. S. (1979). X-linked Recessive Congenital Muscle Fiber Hypotrophy With Central Nuclei: Abnormalities of Growth and Adenylate Cyclase in Muscle Tissue Cultures. Arch Neurol 36: 604-609 [Abstract]  
• Davis, E. A., Gordon, J., Hutchinson, T. E. (1976). Scanning Electron Microscope Studies on Carrots: Effects of Cooking on the Xylem and Phloem. Family and Consumer Sciences Research Journal 4: 214-224 [Abstract]  
• Leppard, G. G. (1974). Rhizoplane Fibrils in Wheat: Demonstration and Derivation. Science 185: 1066-1067 [Abstract]  

Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents