Host mitochondria are recruited to the host-parasite interface. Sometimes, host mitochondria are found within the R. allomycis protoplast within three-membrane vacuoles, which is evidence the R. allomycis protoplast is phagocytizing the host cytoplasm as it grows. As it grows, the R. allomycis protoplast completely fills a portion of the host, which is separated by a host septum. The protoplast develops into a zoosporangium and releases zoospores.
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Protoplast fusion is the joining of cells or cell components to transfer traits between species. For example, the trait of male sterility is transferred from radishes to red cabbages by protoplast fusion. This male sterility helps plant breeders make hybrid crops.
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Mature spores have a two-layered wall, with both perispore and exospore, and their protoplast is fulfilled with lipid drops.
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The coloration of the protoplast is a light blue-green, appearing dark or brown due to optical effects of gas-filled vesicles.
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In some cases, the protoplast skips the thread phase and remains isodiametric. The nuclei then migrate to four points of a tetrahedron and the protoplast cleaves into a tetrad of lobes. Soon after, the tetrad undergoes mitosis and splits again into an octette of haploid cells. Each cell releases a swarmcell with either one long flagellum, 2 unequal flagella, or 2 long flagella.
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During convex plasmolysis, the plasma membrane and the enclosed protoplast shrinks completely from the cell wall, with the plasma membrane's ends in a symmetrically, spherically curved pattern.
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Bynum et al. (1981), p. 344. In 1880, term protoplast was proposed by Hanstein (1880) for the entire cell, excluding the cell wall,Hanstein, J. (1880). Das Protoplasma. Heidelberg.
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Rozella polyphagi was first described in 1938 by F. K. Sparrow as a parasite of Polyphagus laevis, though it also parasitizes Polyphagus euglenae. Rozella polyphagi infects both the prosporangium and the sporangium of the host and exists as an unwalled protoplast within the host. Host mitochondria could be observed within R. polyphagi protoplast vacuoles; cytoplasmic extensions of R. polyphagi around host cytoplasm also occur. This suggests that Rozella polyphagi phagocytizes host cytoplasm.
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This release is then followed by protoplast fusion (conjugation) leading to formation of a diploid zygospore. Sex pheromones termed protoplast-release inducing proteins produced by mt(-) and mt(+) cells facilitate this process. A homothallic strain of Closterium forms selfing zygospores via the conjugation of two sister gametangial cells derived from one vegetative cell. Conjugation in the homothallic strain occurs mainly at low cell density and is regulated by an ortholog of a heterothallic sex- specific pheromone.
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Interaction is measured using a GUS reporter. In order to enable a high-throughput screening the vectors were made gateway compatible. The system is known as the protoplast two hybrid (P2H) system.
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In a study done by M. Weber and H. Halbritter to examine M. arborescens pollen, their findings indicated that there is rapid pollen tube formation. The ultra structure of the pollen protoplast was characterized by many mitochondria, ER strands, dictyosomes, and microtubules. It seemed that they need quick germination since the wall is missing and thus a protective coating around the easily damaged pollen protoplast is absent. Further studies are needed to clarify how the pollen wall and pollen tube are formed.
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Fused protoplast (left) with chloroplasts (from a leaf cell) and coloured vacuole (from a petal). Somatic fusion, also called protoplast fusion, is a type of genetic modification in plants by which two distinct species of plants are fused together to form a new hybrid plant with the characteristics of both, a somatic hybrid. Hybrids have been produced either between different varieties of the same species (e.g. between non-flowering potato plants and flowering potato plants) or between two different species (e.g.
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2008 U.S. Patent # 018293-00006 Hyperthermophile microorganisms to produce Bio-Fuels and other chemicals from carbohydrates in a single bioreactor. 2009 U.S. Patent #018293.000006D. Fusion of Bacterial Protoplast of Clostritridium Spps. to Produce Biofuel.
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When measuring turgor pressure in plants, many things have to be taken into account. It is generally stated that fully turgid cells have a turgor pressure value which is equal to that of the cell and that flaccid cells have a value at or near zero. Other cellular mechanisms taken into consideration include the protoplast, solutes within the protoplast (solute potential), transpiration rates of the plant and the tension of cell walls. Measurement is limited depending on the method used, some of which are explored and explained below.
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W. H. Freeman and Company, New York, 2005. The sole method of reproduction is asexual and azosporic. The content of the cell divide into 2,4 (B), 8(C) sometimes daughter protoplasts. Each daughter protoplast rounds off to form a non-motile spore.
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Harold Hill Smith (April 24, 1910 – October 19, 1994) was an American geneticist who first fused a human cell and a plant cell.Smith HH, Kao KN, Combatti NC (1976). Interspecific hybridization by protoplast fusion in Nicotiana. The Journal of Heredity, 67:123-128, 1976.
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Protoplasts of cells from a petunia's leaf Protoplasts of the moss Physcomitrella patens Protoplast, from ancient Greek (prōtóplastos, "first- formed"), is a biological term coined by Hanstein in 1880 to refer to the entire cell, excluding the cell wall.Hanstein, J (1880). Das Protoplasma. Heidelberg.Sharp, LW (1921).
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This can be resolved by using a backcrossing programme. Thus, mutagenesis is crucial to create new and desirable varieties. According to Yadav et al. other biotechnology techniques which may impact on lentil breeding are micro-propagation using meristamatic explants, callus culture and regeneration, protoplast culture and doubled haploid production.
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By allowing users to control parameters such as droplet size, droplet frequency, temperature, agitation and timing, innovation is unlocked. The Nadia platform enbales applications such as single cell RNA-Seq (scRNA-Seq), single nuclei RNA-Seq (sNuc-Seq), plant protoplast RNA-Seq (ppRNA-Seq) and the encapsulation of cells in Agarose beads.
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R. allomycis zoospores are chemotaxically attached to Allomyces. Once in contact, the zoospore encysts and germinates. The host cell wall is penetrated with an infection tube, and the contents of the zoospore are injected into the host. The infection tube causes an invagination of the host cell membrane, which then envelopes the R. allomycis protoplast.
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The Closterium peracerosum-strigosum- littorale (C. psl) complex is a unicellular, isogamous charophycean alga group that is the closest unicellular relative to land plants. Heterothallic strains of different mating type can conjugate to form zygospores. Sex pheromones termed protoplast-release inducing proteins (glycopolypeptides) produced by mating-type (-) and mating-type (+) cells facilitate this process.
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50px Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. This type of asexual reproduction is unique among the colonial volvocine green algae (Pocock 1953). By contrast, in Eudorina, protoplast rotation is lacking during successive divisions; a spheroidal colony is formed by means of inversion after successive divisions.
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They are typically found to have 5 nuclei per cell, due to the fusion of preosteoclasts. The chlorarachniophytes form multinucleate cells by fusion, being syncytia and not coenocytes. This syncytia is called plasmodium, in the sense of a multinucleate protoplast without a cell wall which exhibits amoeboid movement.Hoek, C. van den, Mann, D.G. and Jahns, H.M. (1995).
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Reticulate evolution has been extensively applied to plant hybridization in agriculture and gardening. The first commercial hybrids appeared in the early 1920s. Since then, many protoplast fusion experiments have been carried out, some of which were aimed at improvement of crop species. Wild types possessing desirable agronomic traits are selected and fused in order to yield novel, improved species.
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Hybrids may also be produced by a technique called protoplast fusion. In this case protoplasts are fused, usually in an electric field. Viable recombinants can be regenerated in culture. Chemical mutagens like EMS and DMS, radiation and transposons are used to generate mutants with desirable traits to be bred with other cultivars – a process known as Mutation Breeding.
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Tafazolli, "In Iranian Mythology" in Encyclopædia Iranica the Iranian epic poem that is based on the ancient legends of Iran. It appears in the epics as the homeland of the protoplast Keyumars, the birthplace of king Manuchehr, the place where king Freydun binds the dragon fiend Aždahāk (Bivarasp), and the place where Arash shot his arrow from.
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The protoplast of the prey is then sucked out into a food vacuole. Remaining contents are then drawn out using pseudopodia. The vampyrellid uses its pseudopodia to move from cell to cell repeating the process. Excess water absorbed from prey cells is removed by numerous small contractile vacuoles on the periphery of the organism, maintaining an only slightly increased size after each meal.
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Bhatla SC, Kiessling J, Reski R (2002): Observation of polarity induction by cytochemical localization of phenylalkylamine-binding receptors in regenerating protoplasts of the moss Physcomitrella patens. Protoplasma 219, 99–105. Protoplasts may also be used for plant breeding, using a technique called protoplast fusion. Protoplasts from different species are induced to fuse by using an electric field or a solution of polyethylene glycol.
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This ratio is known as the polar ratio and depends on the force of gravity. This increase in speed is not a direct result of the force of gravity, but an indirect result. Gravity causes the plant protoplast to settle within the cell wall. Thus, the cell membrane is put into tension at the top, and into compression at the bottom.
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This large nucleus contains 1-2 nucleoli and elongated chromosomes. The reticulate, parietal chloroplast extends over the whole interior of the cell, enveloping the protoplast. Whether these networked strands are narrow or broad varies between species, but with most species these reticula are parallel to the long axis of the cell. At the strand junctions are pyrenoids, covered in starch plates.
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Other types include the foraminate perforation plate (several round openings) and the reticulate perforation plate (a net-like pattern, with many openings). At maturity the protoplast – the living material of the cell – dies and disappears, but the lignified cell walls persist. A vessel element is then a dead cell, but one that still has a function, and is still being protected by surrounding living cells.
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Astrephomene gubernaculifera has two mating types that reproduce to form zygotes. Schematic diagrams of the two mechanisms of spheroidal colony formation in the volvocine algae. In Astrephomene, rotation of daughter protoplasts occurs in conjunction with the movement of basal bodies during successive cell divisions. In Eudorina, protoplast rotation is lacking during successive divisions; a spheroidal colony is formed by means of inversion after successive divisions.
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Tracheids, unlike vessel elements, do not have perforation plates. All tracheary elements develop a thick lignified cell wall, and at maturity the protoplast has broken down and disappeared. The presence of tracheary elements is the defining characteristic of vascular plants to differentiate them from non-vascular plants. The two major functions that tracheids may fulfill are contributing to the transport system and providing structural support.
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The line of Pokucie was founded by Józef Wróblewski, who was the brother of Bazyli, protoplast of the Vilnius line. Józef lived in the area of Kołomyja in Pokucie.Birth certificate of Walerian, son of Józef The descendants of Józef Wróblewski were Walerian Wroblewski, a professor of high school, and his daughter, Wanda Wróblewska-Składzień, a lawyer, commander of WSK AK Tarnow, Lieutenant of AK.
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Plasmolysis is mainly known as shrinking of cell membrane in hypertonic solution and great pressure. Plasmolysis can be of two types, either concave plasmolysis or convex plasmolysis. Convex plasmolysis is always irreversible while concave plasmolysis is usually reversible. During concave plasmolysis, the plasma membrane and the enclosed protoplast partially shrinks from the cell wall due to half-spherical, inwarding curving pockets forming between the plasma membrane and the cell wall.
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The potential to undergo a parasexual cycle under laboratory conditions has been demonstrated in many species of filamentous fungi, including Fusarium monoliforme, Penicillium roqueforti (used in making blue cheesesAlexopolous (1996), et al., p. 12.), Verticillium dahliae, Verticillium alboatrum, Pseudocercosporella herpotrichoides,Hocart MJ, Lucas JA, and Peberdy JF. "Parasexual recombination between W and R pathotypes of Pseudocercosporella herpotrichoides through protoplast fusion." Mycological Research. 1993 August;97(8):977-983.
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Two virus-free isolates were successfully infected by purified TmPV1 using protoplast transfection. Mice challenged with TmPV1-infected T. marneffei isolates showed significantly shortened survival time and higher fungal burden in organs than mice challenged with isogenic TmPV1-free isolates. Transcriptomic analysis showed that TmPV1 causes aberrant expression of various genes in T. marneffei, with upregulation of potential virulence factors and suppression of RNA interference (RNAi)-related genes.
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Furthermore, it is speculated that the spindle itself may also be unicentric. Eventually, microtubules extend from the spindle, and during anaphase, they penetrate through the fenestrae and split the nucleus. Subsequently to telophase, the nucleus reforms, but a phycoplast forms. In addition, a protoplast is found inside the cell wall and is noted to rotate within the wall during cleavage; a process known to occur by the cell undergoing furrowing.
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Fused protoplast (on left), containing both chloroplasts (from a leaf cell) as well as a coloured vacuole (from a petal). Protoplasts can be used to study membrane biology, including the uptake of macromolecules and viruses . These are also used in somaclonal variation. Protoplasts are widely used for DNA transformation (for making genetically modified organisms), since the cell wall would otherwise block the passage of DNA into the cell.
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This species is known to have its spores dispersed by beetles (family Latridiidae). The spores have a two-layered wall, with a dense outer layer with spines, and a fibrous inner layer. During germination, the outer layer splits to create an opening, and more elastic inner layer ruptures later as protoplasm emerges. A remnant of the inner layer may be persistent and adhere to the protoplast after it has emerged from the spore.
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Sphagnurus paluster parasitizes living Sphagnum mosses by forming penetration pegs through hyphae pressure. At the tips of these pegs pectinases are produced to digest the lamella between leaf cells which facilitates entry into both hyaline and chlorophyllous cells. The result is a deterioration of the protoplast and necrosis of the cells. The rate of parasitic expansion is theorized to be related to the amount of available nitrogen in the host and parasite mediums.
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Water molecules travel through the plasma membrane, tonoplast membrane (vacuole) or protoplast by diffusing across the phospholipid bilayer via aquaporins (small transmembrane proteins similar to those responsible for facilitated diffusion and ion channels). Osmosis provides the primary means by which water is transported into and out of cells. The turgor pressure of a cell is largely maintained by osmosis across the cell membrane between the cell interior and its relatively hypotonic environment.
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When arbuscular mycorrhizal fungal hyphae encounter the root of a host plant, an appressorium or 'infection structure' forms on the root epidermis. From this structure hyphae can penetrate into the host's parenchyma cortex. AM need no chemical signals from the plant to form the appressoria. AM fungi could form appressoria on the cell walls of “ghost” cells in which the protoplast had been removed to eliminate signaling between the fungi and the plant host.
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Plants with compromised perception of day length have compromised cold acclimation. Cold increases cell membrane permeability and makes the cell shrink, as water is drawn out when ice is formed in the extracellular matrix between cells. To retain the surface area of the cell membrane so it will be able to regain its former volume when temperature rises again, the plant forms more and stronger Hechtian strands. These are tubelike structures that connect the protoplast with the cell wall.
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Its relative vitality compared to other organelles in unfavourable conditions and its ability to photosynthesize and lodge in other cells demonstrates its high level of autonomy relative to other organelles (Lü et al., 2011). The chloroplast is also thought to have an important role in protoplast regeneration. The literature suggests that the fast rate of repair to photosystem II and transient photoinactivation are mechanisms that this genus uses to help mitigate photodamage from excess sun light (Giovagnetti et al.
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Blooms have been noted in contaminated environments due to excess augmentation of ammonia from industrial waste and are now being associated with the drop in biodiversity in such water bodies. Both sexual and asexual reproduction are possible for species within this genus. In addition, mitosis is well defined in Tetraspora species; particularly investigated in T. gelatinosa. Cell division involves elaborate arrangement of microtubules, basal body complexes and involve the use of structures like phycoplasts and protoplast.
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P. fusiformis has a full life cycle of approximately 5–7 days and reproduces asexually. The reproduction phase creates 1 or 2 zoospores which grow inside of the parent's cell wall until they become new cells. Observed in the laboratory under culture, asexual reproduction begins when the protoplast contracts away from the parental cell wall. In P. fusiformis, the protoplasm contracts near the middle of the cell forming two lobes, as opposed to Pyrocystis lunula, which forms crescent moon-like shapes while dividing.
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The club even had a short-lived ultras group Młoda Nabojka. The fans also frequently appear supporting the Polish national team in other sports, as well as having produced supporter merchandise common for fans of much larger teams, such as scarves and flags. Currently, the fans (and players) maintain good relations with Błękitni Owińska, as well of course their protoplast Karmazyn Warszawa. Their main rivals are listed as the WZPN match observers, Rakieta Biedrusko and referee "Mr Paluszak from Stryków".
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The protoplasm of Oedogonium is contained by a plasma membrane, and consists of a single nucleus, reticulate chloroplasts, cytoplasm and a central vacuole. Cell sap (contained by the central vacuole) is made up of inorganic compounds, excretions and secretions. Between the innermost cell wall and the central vacuole is a thin layer known as the protoplast. The single nucleus is large and oval shaped and sits in the centre of the cell – usually along the membrane and internal to the chloroplast.
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Coprinopsis cinerea can be transformed with exogenous DNA by transformation when the fungus is a protoplast. It was found that disrupting (knockout or RNAi silencing) ku70 homologue can increase gene targeting via increased homologous recombination. Either protoplasts derived from oidia or vegetative mycelium can be used, however, gene targeting was found to be higher by 2% (based on phenotyping) when using vegetative mycelium. Otherwise, insertion of integrative vectors ectopically and with small homologous regions can be used, likely with low transformation efficiency.
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Triploidy is also utilized in salmon and trout farming to induce sterility. Rarely, autopolyploids arise from spontaneous, somatic genome doubling, which has been observed in apple (Malus domesticus) bud sports. This is also the most common pathway of artificially induced polyploidy, where methods such as protoplast fusion or treatment with colchicine, oryzalin or mitotic inhibitors are used to disrupt normal mitotic division, which results in the production of polyploid cells. This process can be useful in plant breeding, especially when attempting to introgress germplasm across ploidal levels.
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A plant cell wall was first observed and named (simply as a "wall") by Robert Hooke in 1665. However, "the dead excrusion product of the living protoplast" was forgotten, for almost three centuries, being the subject of scientific interest mainly as a resource for industrial processing or in relation to animal or human health. In 1804, Karl Rudolphi and J.H.F. Link proved that cells had independent cell walls. Before, it had been thought that cells shared walls and that fluid passed between them this way.
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Arbuscular mycorrhizas, or AM (formerly known as vesicular-arbuscular mycorrhizas, or VAM), are mycorrhizas whose hyphae penetrate plant cells, producing structures that are either balloon-like (vesicles) or dichotomously branching invaginations (arbuscules) as a means of nutrient exchange. The fungal hyphae do not in fact penetrate the protoplast (i.e. the interior of the cell), but invaginate the cell membrane. The structure of the arbuscules greatly increases the contact surface area between the hypha and the cell cytoplasm to facilitate the transfer of nutrients between them.
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Earlier, REMI (restriction enzyme-mediated integration) could be used to insert exogenous DNA into the chromosome to produce mutant strains. This relies on inserting exogenous DNA and restriction enzymes into the protoplast cell, allowing for the enzymes to cut the chromosome at specific sites which match those sites used to produce linearized plasmid DNA with the gene of interest; subsequently, host enzymes ligate the cut sites and thus produce integrated heterologous, exogenous DNA. Although successful, undesirable mutations are likely. Chemical mutagenesis (also random) can also be done.
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Tolerance of high salt conditions can be obtained through several routes. High levels of salt entering the plant can trigger ionic imbalances which cause complications in respiration and photosynthesis, leading to reduced rates of growth, injury and death in severe cases. To be considered tolerant of saline conditions, the protoplast must show methods of balancing the toxic and osmotic effects of the increased salt concentrations. Halophytic vascular plants can survive on soils with salt concentrations around 6%, or up to 20% in extreme cases.
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Methodology varies depending on the organism to transform. While plants can be transformed with a construct introduced into Agrobacterium tumefaciens via agroinfiltration or floral dip, most animal cells would require a viral vector. Some fungi, like yeasts or zygomycota, are susceptible to transformation by dedifferentiating their hyphae to protoplasts and adding Cl2Ca 10–50 mM, Tris-HCl 10 mM, polyethylene glycol (40%) and the DNA construct (> 5µg/ml) to a 10^8 protoplast/ml solution. Under this pH conditions, PEG acts as a binder, promoting protoplasts to clump together and trap introduced DNA strands.
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Agarose plate may sometimes be used instead of agar for culturing organisms as agar may contain impurities that can affect the growth of the organism or some downstream procedures such as polymerase chain reaction (PCR). Agarose is also harder than agar and may therefore be preferable where greater gel strength is necessary, and its lower gelling temperature may prevent causing thermal shock to the organism when the cells are suspended in liquid before gelling. It may be used for the culture of strict autotrophic bacteria, plant protoplast, Caenorhabditis elegans, other organisms and various cell lines.
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Phage lytic enzymes (lysins) produced during bacteriophage infection are responsible for the ability of these viruses to lyse bacterial cells. Penicillin and related β-lactam antibiotics cause the death of bacteria through enzyme-mediated lysis that occurs after the drug causes the bacterium to form a defective cell wall. If the cell wall is completely lost and the penicillin was used on gram-positive bacteria, then the bacterium is referred to as a protoplast, but if penicillin was used on gram-negative bacteria, then it is called a spheroplast.
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The somatic fusion process occurs in four steps: . # The removal of the cell wall of one cell of each type of plant using cellulase enzyme to produce a somatic cell called a protoplast # The cells are then fused using electric shock (electrofusion) or chemical treatment to join the cells and fuse together the nuclei. The resulting fused nucleus is called heterokaryon. # The formation of the cell wall is then induced using hormones # The cells are then grown into calluses which then are further grown to plantlets and finally to a full plant, known as a somatic hybrid.
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Once this reaches the haemocoel, the protoplast flows through the tube and into the fly's haemolymph. The mycelium of the fungus may grow into an area of the brain that controls the behaviour of the fly, forcing it to land on a surface and crawl upwards. The hyphae gradually grow through the whole of the body, digesting the guts, and the fly dies in about five to seven days. When it is critically ill, it tends to crawl to a high point, straighten its hind legs and open its wings, a behaviour that ensures that the fungal spores are dispersed as widely as possible.
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A Bacillus cereus cell that has undergone filamentation following antibacterial treatment (upper electron micrograph; top right) and regularly sized cells of untreated B. cereus (lower electron micrograph) Antibiotics can induce a broad range of morphological changes in bacterial cells including spheroplast, protoplast and ovoid cell formation, filamentation (cell elongation), localized swelling, bulge formation, blebbing, branching, bending, and twisting. Some of these changes are accompanied by altered antibiotic susceptibility or altered bacterial virulence. In patients treated with β-lactam antibiotics, for example, filamentous bacteria are commonly found in their clinical specimens. Filamentation is accompanied by both a decrease in antibiotic susceptibility and an increase in bacterial virulence.
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While chromosomal integration of genes creates a stable transformant, transient expression allows short-term experiments to be done using labeled or modified genes in C. merolae. Transient expression can be achieved using a polyethylene glycol (PEG) based method in protoplasts (plant cells with the rigid cell wall enzymatically eliminated), and because C. merolae lacks a cell wall, it behaves much as a protoplast would for transformation purposes. To transform, cells are briefly exposed to 30% PEG with the DNA of interest, resulting in transient transformation. In this method, the DNA is taken up as a circular element and is not integrated into the genome of the organism because no homologous regions exist for integration.
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Since the cell wall is required for bacterial survival, but is absent in some eukaryotes, several antibiotics (notably the penicillins and cephalosporins) stop bacterial infections by interfering with cell wall synthesis, while having no effects on human cells which have no cell wall, only a cell membrane. There are two main types of bacterial cell walls, those of gram- positive bacteria and those of gram-negative bacteria, which are differentiated by their Gram staining characteristics. For both these types of bacteria, particles of approximately 2 nm can pass through the peptidoglycan. If the bacterial cell wall is entirely removed, it is called a protoplast while if it's partially removed, it is called a spheroplast.
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NOAA MERIS image of large cyanobacterial bloom confirmed as M. aeruginosa Lake Albert in Wagga Wagga, Australia As the etymological derivation implies, Microcystis is characterized by small cells (of only a few micrometers diameter), which lack individual sheaths. Cells usually are organized into colonies (large colonies of which may be viewed with the naked eye) that begin in a spherical shape, but lose their coherence to become perforated or irregularly shaped over time in culture. Recent evidence suggests of the drivers of colony formation is disturbance / water column mixing. The protoplast is a light blue-green color, appearing dark or brown due to optical effects of gas-filled vesicles; this can be useful as a distinguishing characteristic when using light microscopy.
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Protoplasm is the living part of a cell that is surrounded by a plasma membrane. In some definitions, it is a general term for the cytoplasm (e.g., Mohl, 1846), but for others, it also includes the nucleoplasm (e.g., Strasburger, 1882). For Sharp (1921), "According to the older usage the extra- nuclear portion of the protoplast [the entire cell, excluding the cell wall] was called "protoplasm," but the nucleus also is composed of protoplasm, or living substance in its broader sense. The current consensus is to avoid this ambiguity by employing Strasburger's [(1882)] terms cytoplasm [coined by Kölliker (1863), originally as synonym for protoplasm] and nucleoplasm ([term coined by van Beneden (1875), or] karyoplasm, [used by] Flemming [(1878)])".Sharp, L. W. (1921). Introduction To Cytology. New York: McGraw Hill, p. 25.Strasburger, E. (1882).
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Section two establishes various definitions, including section 2(3)(a) which strictly defines "genetically engineered" by specific genetic engineering techniques, and differentiated from selective breeding. These specific genetic engineering techniques include various recombinant DNA and RNA methods such as micro- injection, electroporation, micro-encapsulation, liposome fusion, protoplast fusion or other "hybridization techniques that overcome natural physiological, reproductive or recombination barriers, where the donor cells or protoplasts do not fall within the same taxonomic family, in a way that does not occur by natural multiplication or natural recombination." Section three requires that "any food offered for retail sale" be labeled "clearly and conspicuously" if it contains genetically-engineered ingredients, with certain exceptions. Exemptions consistent with current federal regulations include prepared foods such as those coming from a restaurant, meat from animals fed genetically engineered feeds, alcoholic beverages and foods processed with GE enzymes.
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