Protoplasts fungal

The ability to enzymically remove fungal cell walls and produce a protoplast has been exploited to generate strains capable of enhanced ethanol production or the metabolism of novel combinations of carbohydrates. Once protoplasts are formed they may be fused by incubation in polyethylene glycol (PEG) and calcium ions, which induces membrane breakdown. Selection of the resulting... 

Dron, M., Clouse, S.D., Dixon, R.A., Lawton, M.A., Lamb, C.J. 1988. Glutathione and fungal elicitor regulation of a plant defense gene promoter in electroporated protoplasts. Proc. Natl. Acad. Sci. 85 6738-6742. 

Pioneering experiments were carried out in the field of protoplast fusion (using bacterial and fungal protoplasts) leading to internationally recognized outstanding results. Significant advances were also made in the field of plant protoplast fusion and practical application has been initiated. 

Fungal Protoplasts, edited by John F. Peberdy and Lajos Ferenczy... 

The mechanism by which nM XGOs are perceived by plant cells is unknown. However, the specific requirement for an a-L-fucose residue for biological activity coupled with their effectiveness at very low concentrations, suggests that they interact with a specific receptor. Radioactively labelled XGOs do not readily enter the protoplast [25,26], and thus the most likely location of any receptor would be in the plasma membrane. Receptors for some fungal oligosaccharins have been clearly demonstrated in higher plants [27-30], but comparable demonstrations of XGO receptors have not yet been published. 

Given that the polyene-binding capacity of the cell wall has been satisfied (obviously this wall binding capacity only applies to eukaryotes with cell walls but not to fungal protoplasts, protozoan or mammalian cells) the polyene molecule will reach the cell membrane. 

Protoplasts, produced by enzymatic hydrolysis of the cell walls, have been used as a source of plant organelles and could be used as a source of soluble enzymes, but the methods can only be applied to relatively soft tissues and require prolonged exposure of tissues to cell wall degrading enzymes >. In addition, most of the fungal enzyme preparations that ea e used contain such undesirable products as proteases, ribonucleases, peroxidases and phenolics. ... 

One of our first observations was on the subcellular distribution of ACP In spinach mesophyll cells. In 1979 we found that when protoplasts were gently lysed and their organelles seperated on sucrose gradients, essentially all of the ACP present could be attributed to the chloroplast fraction (2). This result revealed that plant mesophyll cells differ from animal and fungal cells by the absence of fatty acid synthesis In the cytoplasm. It Is now known that plastlds are also a major site of fatty acid synthesis In many non-green plant tissues although It has not been established whether other subcellular sites In these tissues also contribute to FAS. 

Peberdy, J. F. Mycolytic enzymes. In Fungal protoplasts - applications in biochemistry cmd genetics, Peberdy, J. F., Ferenczy, L., Ed., Marcel Dekker New Yoik, 1985, pp. 31 14. 

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