Vacuole plant cell

In yeasts and other fungi, the vacuole is an important organelle sharing some properties with the mammalian lysosome (an acidic compartment containing a variety of hydrolytic enzymes) and with the plant cell vacuole (responsible for metabolite storage and for cytosolic ion and pH homeostasis) [18,19]. 

Most anionic FITC-labeled fluorochromes microinjected into the cytoplasm are compartmented by the plant cell vacuoles at rates that depend on their molecular size (14,15). 

Plants use osmotic pressure to achieve mechanical rigidity. The very high solute concentration in the plant cell vacuole draws water into the cell (Fig. 2-13). The resulting osmotic pressure against the cell wall (turgor pressure) stiffens the cell, the tissue, and the plant body. When the lettuce in your salad wilts, it is because loss of water has reduced turgor pressure. Sudden alterations in turgor pressure produce the movement of plant... 

Plant cell vacuole Plant cells usually contain one or more membrane-bounded vacuoles. These are used to store nutrients (e.g. sucrose), water, ions and waste products (especially excess nitrogen-containing compounds). Like lysosomes in animal cells, vacuoles have an acidic pH maintained by H+ pumps in the membrane and contain a variety of degradative enzymes. Entry of water into the vacuole causes it to expand, creating hydrostatic pressure (turgor) inside the cell which is balanced by the mechanical resistance of the cell wall. 

Aglucones are released by p-glucosidase on a pest attack from their preinfectional glucosidic precursors deposited in the plant cell vacuole, as will be shown below. Furthermore, aglucones can be passively set free into the environment by rotting plant material [62] or actively by root exudation [63]. An overview on benzoxazinone aglucones is given in Fig. (3). 

Lochmann, H., Bazzanella, A., and Bachmann, K., Analysis of solutes and metabolites in single plant cell vacuoles by capillary electrophoresis, J. Chromatogr. A, 817, 337-343, 1998. 

The alkaloid productivity and the storage capacity in cultured plant cells can be influenced by the pH gradient between the medium and the accumulation sites inside the plant cell (vacuoles). A shift in the medium pH from low to high value was used to release the intracellularly stored alkaloids into the culture medium in cell suspension culture of C. roseus [42]. Similarly, transient modifications in the medium pH value led to the release of indole alkaloids in culture medium during immobilized cell cultivation of C. roseus [43]. 

Organic acids such as citric, malic, acetic, and oxalic are commonly contained in plant cell vacuoles of fresh leaves and stems. Hot alcohol extracts are filtered and concentrated prior to spotting on TLC plates (Harborne, 1984). 

D. N. De, Plant Cell Vacuoles, CSIRO Publishing, Collingwood, Australia, 2000. 

By accumulating water, the vacuole allows the plant cell to grow dramatically in size with no increase in cytoplasmic volume. 

Leigh, R.A. (1983). Methods, progress and potential for use of isolated vacuoles in studies of solute transport in higher plant cells. Physiologic Plantarum, 57,390-6. 

Wagner, G.J. (1983). Higher plant vacuoles and tonoplasts. In Isolation of Membrane and Organelles from Plant Cells, ed. J.L. Hall and A.L. Moore, pp. 83-118. London Academic Press. 

The perceived sensitivity of plant cells to the hydrodynamic stress associated with aeration and agitation conditions is typically attributed to the physical characteristics of the suspended cells, namely their size, the presence of a cell wall, the existence of a large vacuole, and their tendency to aggregate. Table 1 illustrates some of the differences between plant cells and other biological systems. Chalmers [19] attributed shear sensitivity in mammalian cultures at least in part to the fact that these cells occur naturally as part of a tissue, surrounded by other cells. The same is true for plant cells. The more robust microbial systems, on the other hand, exist in nature as single organisms or mycelial structures, very close to the forms they assume in submerged culture. 

As for anthocyanins, betalains are found in vacuoles and cytosols of plant cells. From the various natural sources of betalains, beetroot (Beta vulgaris) and prickly pear cactus (Opuntia ficus indica) are the only edible sources of these compounds. In the food industry, betalains are less commonly used as natural colorants from plant sources than anthocyanins and carotenoids, probably related to their more restricted distribution in nature. To date, red beetroot is the only betalain source exploited for use as a natural food coloring agent. The major betalain in red beetroot is betanin (or betanidin 5-0-P-glucoside). Prickly pear fruits contain mainly (purple-red) betanin and (yellow-orange) indicaxanthin and the color of these fruits is directly related to the betanin-to-indicaxanthin ratio (99 to 1, 1 to 8, and 2 to 1, respectively in white, yellow, and red fruits)." ... 

Besides, it is known that the culture medium acts as a common external sink like a lamella (15) or a vacuole (19), in which polysaccharides, enzymes and other metabolites are secreted during growth. Consequently, the growth of plant cell suspensions is a complex process, connected with structural and metabolite changes both in the cell wall and in the culture medium, involving a complex of hydrolytic enzymes. 

ALFENITO, M.R., SOUER, E GOODMAN, C.D., BUELL, R., MOL, J., KOES, R., WALBOT, V., Functional complementation of anthocyanin sequestration in the vacuole by widely divergent glutathione 5-transferases, Plant Cell, 1998,10,1135-1149. 

M., The TRANSPARENT TESTA12 gene of Arabidopsis encodes a multidrug secondary transporter-like protein required for flavonoid sequestration in vacuoles of the seed coat endothelium, Plant Cell, 2001,13, 853-871. 

Marty F, BrantonD, Leigh RA. Plant vacuoles, in The Biochemistry of Plants. The Plant Cell (Tobert NE, ed.), Academic Press, New York, 1980, pp. 625-658. 

Nakamura K, Matsuoka K. Protein targeting to the vacuole in plant cells. Plant... 

Verbelen JP. Tao W. Mobile vacuole ripples are common in plant cells. Plant Cell Reports 1998 17 917-920. 

In spite of the variety of appearances of eukaryotic cells, their intracellular structures are essentially the same. Because of their extensive internal membrane structure, however, the problem of precise protein sorting for eukaryotic cells becomes much more difficult than that for bacteria. Figure 4 schematically illustrates this situation. There are various membrane-bound compartments within the cell. Such compartments are called organelles. Besides the plasma membrane, a typical animal cell has the nucleus, the mitochondrion (which has two membranes see Fig. 6), the peroxisome, the ER, the Golgi apparatus, the lysosome, and the endosome, among others. As for the Golgi apparatus, there are more precise distinctions between the cis, medial, and trans cisternae, and the TGN trans Golgi network) (see Fig. 8). In typical plant cells, the chloroplast (which has three membranes see Fig. 7) and the cell wall are added, and the lysosome is replaced with the vacuole. 

At an appropriate intensity level of ultrasound, intracellular microstreaming has been observed inside animal and plant cells with rotation of organelles and eddying motions in vacuoles of plant cells [9]. These effects can produce an increase in the metabolic functions of the cell that could be of use in both biotechnology and microbiology, especially in the areas of biodegradation and fermentation. 

---