Cell wall composition

To characterize modifications in the cell wall composition of transgenic invertase plants we determined the distribution of neutral saccharides (Fig. 1). Obviously, the relative amounts of fucose and mannose were slightly reduced in leaf 6 of transgenic plants, whereas arabinose was increased. The other saccharides remained unchanged. 

Modifications of the cell wall composition of released cells occured during the maceration (Fig. 5). In pectic polysaccharide, galactose increased whereas galacturonic acid and arabinose decreased. Cellulose and hemicellulose compositions were not modified. 

S. Bartnicki-Garcia and E. Lippman. Fungal cell wall composition. Handbook of Microbiology (A. L. Laskin and H. L. Lechvaluer, eds.). Chemical Rubber, Cleveland. Ohio. 1973, p. 229. 

Marita, J. M. Vermerris, W. Ralph, J. Hatheld, R. D. Variations in the cell wall composition of maize brown midrib mutants.. /. Agric. Food Chem. 2003, 51, 1313-1321. 

The cell organellae in woody plants are the nucleus, mitochondrion, rough-endoplasmic reticulum (r-ER), smooth endoplasmic reticulum (s-ER), Golgi-body, plastid, vacuole, microbody, etc. Their functions are very complicated, and some have definite roles in the biosynthesis of cell-wall components. Hence, changes in size of cell organellae are likely to occur, since cell-wall composition depends upon the stage of wall development. 

Allan, G. R. and Hadwiger, L. A. (1979). The fungicidal effect of chitosan on fungi of varying cell wall composition. Exp. Mycol. 3, 285-287. 

While for some plant species the cell wall composition has been studied, the actual three-dimensional organization of the polysaccharides in the cell wall has not been fully elucidated. Moreover, it appears that while some aspects are constant for all walls (i.e., the presence of similar types of polysaccharides), the relative proportion and fine structure of the polysaccharides may be different, and thus the way they are organized in the wall may be different. Determination of the composition of polysaccharides in cell walls is commonly done by chemical analytical methods, but prior to determining the composition or structure of the polysaccharides in cell walls, the walls must first be isolated from the plant tissues and separated from the intracellular material. 

Digestibility studies with brown midrib mutants of maize (Bames et al., 1971 Barriere et al., 1994 2004 Fontaine et al., 2003), sorghum (Porter et al., 1978 Akin et al., 1986) and pearl millet (Chemey et al., 1990 Akin et al., 1991) have indeed shown that some of the mutants are considerably more easily digestible. The fact that some of the mutants do not show much improvement indicates that not all changes in cell wall composition are automatically of practical use. 

Fontaine, A. S., Bout, S., Barriere, Y., and Vermerris, W., 2003, Variation in cell wall composition among forage maize (Zea mays L.) inbred lines and its impact in digestibility analysis of neutral detergent fiber composition by pyrolysis-gas chromatography-mass spectrometry, J. Agric. FoodChem. 51 8080-8087. 

Vermerris, W., Thompson, K. J., and McIntyre, L. M., 2002, The maize Brown midrib I locus affects cell wall composition and plant development in a dose-dependent manner, Heredity 88 450-457. 

Table 10. Distribution of amino acids (residues/1000) in cell contents and cell walls of 6 species of diatoms from various habitats. Column a distribution in cell contents Column b cell walls. Bottom of table emphasizes the difference (Column b - Column a) between cell-wall composition and cell contents for those amino acids which show consistent trends. The sponge spicules are from Ctiona celata, and the sponge tissue is from an unidentified siliceous sponge. AA amino acids HA hexosamines... 

Albrecht KA, Wedin WF, Buxton DR. 1987. Cell-wall composition and digestibility of alfalfa stems and leaves. Crop Sci 27 735-741. 

There are different DNA purification protocols for different bacterial organisms, based on their different cell wall compositions. Purification of macromolecular DNA can be achieved through subsequent steps of phenol extraction (using Tris-saturated phenol to prevent the DNA from getting redissolved in the phenol). The... 

A Severin, AM Figueiredo, A Tomasz. Separation of abnormal cell wall composition from penicillin-resistance through genetic transformation of Streptococcus pneumoniae. J Bacteriol 178 1788-1792, 1996. 

Therefore, the three vitamin deficiencies so far studied in detail appear to affect amino acid transport and accumulation in similar but indirect ways. The accumulation defect is most pronounced in vitamin B6-deficient cells, for which there is also strong evidence implicating an abnormality in cell wall composition as a likely source of the change in transport activity. Direct evidence for a cell wall change in biotin- and pantothenate-deficient cells has not yet been obtained. The possibility remains, therefore, that the change in accumulation activity may be caused by an abnormality in some other structural component such as the peripheral cell membrane. 

Agricultural systems are notorious for their variability (e.g., harvest yield) from year to year, location to location, and variety to variety. Characteristics other than yield (e.g., plant height, pigmentation patterns, cell wall composition, nutritional quality, resistance to diseases, etc.) are also influenced by some combination of these and other factors. Each phenotype is most likely influenced by different combinations of genetic and environmental factors. 

Genetic Factors That May Contribute to Cell Wall Compositional Variability... 

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