Protoplast

About: Protoplast is a research topic. Over the lifetime, 5474 publications have been published within this topic receiving 122468 citations.

Protoplast Fusion of Trichoderma reesei, Using Immature Conidia

Abstract: Protoplast fusion of strains derived from Trichoderma reesei QM9414 and QM9136 and the segregation of the resulting fusants were studied. Combinations of protoplasts prepared from young conidia with double amino acid requirements, one of which was a common requirement and the other uncommon, were fused in the presence of polyethylene glycol 6000. Fusants were selected as regenerant colonies requiring only the commonly deficient amino acid. The frequency of fusion was 0.9 x 10 to 4.0 x 10 for the starting conidia and 3.0 x 10 to 4.9 x 10 for the regenerated protoplasts, which was significantly higher than the expected reversion frequencies by mutation. Conidia generated on the fusant colonies showed diverse phenotypes, i.e., parental types (40 to 80%) and nonparental types (20 to 60%). Colonies developed from single conidia of the nonparental phenotype contained special spots called "knobs" that have a higher density of mycelia. The phenotype of the knobs was again varied among prototrophs, parental types, and recombinant types; and their traits were inherited stably. The phenotype of the mycelia in the nonknob part was essentially the same as that of the original conidia and again formed knobs in colonies upon transfer of a piece of mycelia to a fresh medium. The conidial DNA content of the knob clone was almost the same as that of the parents, but that of the fusants was 1.2 to 2.0 times higher than that of the parents. From these results, we conclude that knobs are the segregants from the fusants. One knob clone showed twice the carboxymethyl cellulose hydrolyzing activity of the parents, suggesting the possibility of breeding T. reesei cells by the protoplast fusion technique.

The physiological properties of plant protoplasts

Abstract: Introduction: The Use of Plant Protoplasts in Physiological Research (With 1 Figure).- Applications of Protoplast Technology.- Properties of Some Enzymes Used for Protoplast Isolation (With 3 Figures).- Isolation of Maize Protoplasts from the Root Cap and Apex (With 2 Figures).- Plant Protoplast Viability (With 2 Figures).- Isolation of Plasma Membrane from Ryegrass (Lolium multiflorum) Endosperm Protoplasts (With 2 Figures).- The Use of Protoplasts in the Study of Coated Vesicles (With 3 Figures).- Membrane Transport in Protoplasts (With 2 Figures).- The Binding of Anion Transport Inhibitors on the Plasmalemma Isolated from Corn Root Protoplasts (With 6 Figures).- Intracellular Transport of Metabolites in Protoplasts: Transport Between Cytosol and Vacuole (With 1 Figure).- Compartmentation of Metabolite Pools in Protoplasts: Chloroplasts, Mitochondria, Cytosol/Vacuole (With 1 Figure).- Protoplast Evacuolation (With 2 Figures).- Protoplasts in Studies of Vacuolar Storage Compounds (With 9 Figures).- Distribution of Saccharides Between Cytoplasm and Vacuole in Protoplasts (With 3 Figures).- Anthocyanin Containing Vacuoles Isolated from Protoplasts of Daucus carota Cell Cultures (With 1 Figure).- Vacuolar pH Variability in a Protoplast Population (With 4 Figures).- Mitotic Cycle of Mesophyll Protoplasts (With 2 Figures).- The Use of Guard Cell Protoplasts to Study Stomatal Physiology (With 6 Figures).- Regulation of Volume Changes in Guard Cell Protoplasts (With 3 Figures).- Wall Regeneration in Protoplasts of Higher Plants (With 3 Figures).- Glucan Synthases and Cell-Wall Regeneration in Fungal Protoplasts (With 3 Figures).- Fatty Acids in Protoplasts (With 3 Figures).- Proline in Protoplasts: The Chemical Potential of Proline and Stress Sensitivity of Cells (With 2 Figures).- The Biosynthesis and Catabolism of Indole-3-Acetic Acid in Protoplasts (With 3 Figures).- Auxin Receptors in Tobacco Leaf Protoplasts (With 3 Figures).- Some Physiological Properties of Protoplasts from Gravireacting Maize Roots (With 2 Figures).- Protoplasts and Gravireactivity (With 6 Figures).- Proton Extrusion in Protoplasts: Fusicoccin and Cytokinin Effects.- Protoplast Growth and Photoregulation (With 1 Figure).- Photorespiratory Metabolism in Protoplasts (With 3 Figures).

Formation and regeneration of Penicillium chrysogenum protoplasts

Abstract: 1. High yields of protoplasts from Penicillium chrysogenum Wisc. 49,2105 were obtained by using a combined enzyme system containing either Cellulase from Oxoporus plus an extract of Helix pomatia gut juice, or cellulase plus an enzyme preparation from the culture filtrate of Streptomyces graminofaciens ATCC 12,705. When 15 h old mycelium was incubated with one of these enzyme systems in 0.55 M NaCl at pH 5.6 nearly all of the mycelium was transformed into protoplasts within 4–5 h. 2. The process of protoplast regeneration was studied both on solid and in liquid media. Approximately 50% of the protoplasts regenerated within 8–10 h. Addition of yeast extract to the medium accelerated the speed of regeneration. Microscopically, 3 patterns were seen by which protoplasts could regenerate to normal mycelium.

Protoplast dehydration correlated with heat resistance of bacterial spores.

Abstract: Water content of the protoplast in situ within the fully hydrated dormant bacterial spore was quantified by use of a spore in which the complex of coat and outer (pericortex) membrane was genetically defective or chemically removed, as evidenced by susceptibility of the cortex to lysozyme and by permeability of the periprotoplast integument to glucose. Water content was determined by equilibrium permeability measurement with 3H-labeled water (confirmed by gravimetric measurement) for the entire spore, with 14C-labeled glucose for the integument outside the inner (pericytoplasm) membrane, and by the difference for the protoplast. The method was applied to lysozyme-sensitive spores of Bacillus stearothermophilus, B. subtilis, B. cereus, B. thuringiensis, and B. megaterium (four types). Comparable lysozyme-resistant spores, in which the outer membrane functioned as the primary permeability barrier to glucose, were employed as controls. Heat resistances were expressed as D100 values. Protoplast water content of the lysozyme-sensitive spore types correlated with heat resistance exponentially in two distinct clusters, with the four B. megaterium types in one alignment, and with the four other species types in another. Protoplast water contents of the B. megaterium spore types were sufficiently low (26 to 29%, based on wet protoplast weight) to account almost entirely for their lesser heat resistance. Corresponding values of the other species types were similar or higher (30 to 55%), indicating that these spores depended on factors additional to protoplast dehydration for their much greater heat resistance.