BACKGROUND Genetic engineering remains a major challenge in oil palm (Elaeis guineensis) because particle bombardment and Agrobacterium-mediated transformation are laborious and/or inefficient in this species, often producing chimeric plants and escapes. Protoplasts are beneficial as a starting material for genetic engineering because they are totipotent, and chimeras are avoided by regeneratin...

Large numbers of vacuoles (10(6)-10(7)) have been isolated from Sorghum bicolor protoplasts and analyzed for the cyanogenic glucoside dhurrin. Leaves from light-grown seedlings were incubated for 4 hours in 1.5% cellulysin and 0.5% macerase to yield mesophyll protoplasts which then were recovered by centrifugation, quantitated by a hemocytometer, and assayed for cyanogenic glucosides. Mature va...

Protoplasts are plant cells that have had their cell walls enzymatically removed. Isolation of protoplasts from different plant tissues was first reported more than 40 years ago and has since been adapted to study a variety of cellular processes, such as subcellular localization of proteins, isolation of intact organelles and targeted gene-inactivation by double stranded RNA interference (RNAi)...

A method has been developed for observing membrane transport in isolated protoplasts. Transport of sugars and amino acids has been studied in protoplasts isolated from the mesophyll of Pisum sativum L. That uptake was not due to passive diffusion through damaged membranes was demonstrated by supplying simultaneously two sugar stereoisomers, the one (3)H-labeled and the other (14)C-labeled. The ...

Among protoplasts released from cells of Bacillus megaterium grown at 20, 30, or 37 C, osmotic swelling in NaCl solution at a given external osmotic pressure was greatest for protoplasts from cells grown at 20 C and least for protoplasts from cells grown at 37 C. Protoplasts from cells grown at lower temperaturs were also less stable to osmotic shock and lysed at higher external osmotic pressur...

Gene expression in the aleurone and endosperm is highly regulated during both seed development and germination. Studies of alpha-amylase expression in the aleurone of barley (Hordeum vulgare) have generated the current paradigm for hormonal control of gene expression in germinating cereal grain. Gene expression studies in both the aleurone and endosperm tissues of maize (Zea mays) seed have bee...

This study develops polydimethylsiloxane microfluidics to enable real-time collection and lysis of Phalaenopsis protoplasts and to analyze and compare the protoplast collecting efficiency of a concave sieving array with that of a convex–concave sieving array. Each set of microfluidics comprises a main flow channel and a protoplast sieving array with collecting channels. The protoplasts were iso...

The conditions for optimal formation and regeneration of protoplasts of Streptomyces clavuligerus were established. The optimal temperature for regeneration of protoplasts and for transformation was 26 degrees C in three different regeneration media. The best efficiency of transformation was obtained with 40% polyethylene glycol 1000. The efficiencies of regeneration and transformation increase...

The effects of some factors on the preparation and regeneration of protoplasts from the taxol-producing fungus Nodulisporium sylviforme were discussed in this paper, including recombination of various enzymes, digesting time and temperature, and pH value. The results showed that the highest preparation frequency of protoplasts is a concentration of 2.0×10 protoplasts per microlitre. The mutagen...

Alveolar macrophages freshly harvested from normal and immunized rabbits were parasitized with yeast cells and protoplasts of Histoplasma capsulatum. Macrophages obtained from either normal or sensitized rabbits failed to phagocytize protoplasts, whereas, the yeast cells were actively ingested. There was no detectable intracellular killing by macrophages. A serological similarity was found betw...