Transgenic plants production

Nessler, C.L., Metabolic engineering of plant secondary products. Transgenic Res. 3, 109, 1994. 

Products released by the action of PL have previously been reported to act as elicitors of plant defense reactions (24,25,26,27). Accordingly, the transgenic plants described in this report provides an excellent mutant collection for the study of factors conferring resistance against Envinia carotovora bacteria. 

At the moment, strategies for the production of transgenic plants are already used for maize, tobacco, potato, and rice. The main purpose is to increase their resistance toward diseases [63]. Some plants also get newly introduced products, such as vitamins [64]. Another purpose of transgenic plants is their use for production of vaccines for instance hepatitis B vaccine... 

The morphology of AM fungal structures developing outside and inside the root is conserved even in the rhizosphere of transgenic plants, where accumulation of antifungal plant defense products—such as lytic enzymes (e.g., chi-... 

In summary, many alternative poly(3HB) and poly(3HB-co-3HV) producing strategies have been demonstrated in the past which might be considered for economic evaluation and future production processes. However, it should not be forgotten that all of these bacterial processes may some day have to compete with future alternative processes based on the production of poly(3HB) and poly(3HB-co-3HV) in transgenic plants [38-40]. 

The wild type ilvA gene was modified to target the protein to the plastid and expressed in A. thaliana. Transgenic plants showed a 20-fold increase in levels of 2-ketobutyrate as well as a large increase in 2-aminobutyrate, the transaminated product of 2-ketobutyrate [27, 41]. The levels of threonine remained stable whereas isoleucine concentration increased. Constitutive expression of the ilvA protein along with bktB, phaA, and phaC proteins in the plastids of A. thaliana led to the synthesis of poly(3HB-co-3HV) in the range of 0.2 - 0.8 % dry weight, with a HV level between 4-17 mol % [27,41]. Co-expression of the iso-... 

Although the amount of poly(3HB-co-3HV) produced in transgenic plants is at present lower than poly(3HB), the demonstration of co-polymer synthesis in seeds of transgenic B. napus represent an important step in the development of crop plants for the production of PHA. 

There are no published reports in the scientific literature on the extraction and purification of PHA from transgenic plant material on the medium- to large-scale necessary for commercial production of PHA in agricultural crops. There are, however, a number of issued patents and patent applications which describe... 

Short production cycle time Seeds can be sprouted at a relatively high temperature, which reduces the production cycle time to only 2-5 days. This compares favorably to the growth of transgenic plants in open fields (months) or to the production of pharmaceuticals in mammalian cells (weeks). 

The most widely studied therapeutic proteins produced in plants include monoclonal antibodies for passive immunotherapy and antigens for use as oral vaccines [40]. Antibodies against dental caries, rheumatoid arthritis, cholera, E. coli diarrhea, malaria, certain cancers, Norwalk virus, HIV, rhinovirus, influenza, hepatitis B virus and herpes simplex virus have been produced in transgenic plants. However, the anti-Streptococcus mutans secretory antibody for the prevention of dental caries is the only plant-derived antibody currently in Phase II clinical trials [40]. Until recently, most antibodies were expressed in tobacco, potato, alfalfa, soybean, rice and wheat [9], It has been estimated that for every 170 tons of harvested tobacco, 100 tons represents harvested leaves. A single hectare could thus yield 50 kg of secretory IgA [3, 41]. Furthermore, it has been estimated that the cost of antibody production in plants is half that in transgenic animals and 20 times lower than in mammalian cell cul-... 

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