In exploring the role of the chloroplast in the multiplication of turnip yellow mosaic virus, the biosyntheses of the major viral polyamine, spermidine, as well as that of the tetramine, spermine were studied. The synthesis of these polyamines from [2-(14)C]methionine in protoplasts of Chinese cabbage leaf cells derived from healthy plants or those infected by turnip yellow mosaic virus were ex...

The tissue and subcellular distribution of prephenate aminotransferase, an enzyme of the shikimate pathway, was investigated in protoplasts from leaves of Sorghum bicolor. Activity was detected in purified epidermal and mesophyll protoplasts, and in bundle sheath strands. After fractionation of mesophyll and epidermal protoplasts by differential centrifugation, 92% of the total prephenate amino...

Protoplasts isolated from tobacco leaves were inoculated with cucumber mosaic virus (CMV) using a method slightly modified from that developed for inoculating tobacco mosaic virus. Multiplication of CMV was demonstrated by staining the protoplasm with fluorescent CMV-antibody, by the electron microscopy of ultrathin sections, and by assaying the infectivity in protoplasts. Seventy to 90% of pro...

BACKGROUND During heterologous protein production using recombinant microbes, the protein tends to accumulate in the cell and may not be secreted. Here, we studied the production of secretory cutinase (heterologous protein) by recombinant Saccharomyces cerevisiae protoplasts. FINDINGS Recombinant S. cerevisiae cells (i.e., cells into which the cutinase gene was transferred) secreted trace amo...

It has long been realised that the study of isolated protoplasts offers a potentially new approach to problems of plant cell biology. For this potential to be fully realised, intact protoplasts must be produced, free from contamination by cell debris, on a scale sufficiently large to enable biochemical and physiological experiments to be performed. This aim, though not impossible as has been su...

Egg cell protoplasts were isolated from the gametophyte of the fern, Struthiopteris niponica (Kunze) Nakai. Archegonia were excised from the prothallia and then digested in an enzyme solution that contained Cellulase "Onozuka" RS and Macerozyme R-10. After 3 hours of incubation, the egg cell protoplasts had separated completely from the somatic cells. The protoplasts had such cytological featur...

Protoplasts have been widely used for genetic transformation, cell fusion, and somatic mutation due to the absence of a cell wall. However, without the protection of a cell wall, protoplasts are easy to rupture and aggregate during washing, collecting, and gene transfection. In this work, we propose a simple and effective silica/alginate two-step method to immobilize protoplasts with advantages...

A mass spectrometric method combining (16)O/(18)O and (12)C/(13)C isotopes was used to quantify the unidirectional fluxes of O(2) and CO(2) during a dark to light transition for guard cell protoplasts and mesophyll cell protoplasts of Commelina communis L. In darkness, O(2) uptake and CO(2) evolution were similar on a protein basis. Under light, guard cell protoplasts evolved O(2) (61 micromole...

OBJECTIVE Aluminum toxicity is a major limiting factor with regard to crop production and quality in most acidic soils around the world. We propose the use of C. arabica L. protoplasts to evaluate the toxic effects of aluminum, the nuclear localization of aluminum and propensity of aluminum to cause DNA damage. RESULTS After protoplasts were exposed to aluminum (Al) for varying periods of tim...

Callus cells of rice (Oryza sativa L.) that were actively dividing in suspension culture had lost the ability to divide during the isolation process of protoplasts. Factors influencing the protoplast viability were examined using highly purified preparations of cellulase C(1), xylanase, and pectin lyase, which were essential enzymes for the isolation of protoplasts from the rice cells. The trea...