Development of transgenic plants

The most recent twist in the use of recombinant DNA technology to produce drugs has been the development of transgenic plants with many of the capabilities of transgenic animals. Some authorities refer to this field of research as molecular farming and call the products of their research farmaceuticals. 

Stoop, J.M., Plant Genes for Fructosyltransferase and Their Use in the Development of Transgenic Plants with Embryos Rich in Fructan, U.S. Patent 2004073975, 2004. 

For decades, fungi have been a valuable and preferred source of enzymes and secondary metabolites because of their ease of isolation, readily manipulative cultivation conditions, greater biomass production, and downstream processing. Fungal chitinases, in particular, strains of Trichoderma have been studied extensively to identify, isolate, clone and express a number of genes responsible for a variety of chitinases production especially in the development of transgenic plant varieties. Other than the biocontrol activities... 

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-... 

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. 

When the expression of CYP79B2 was driven by the 35S promoter, a 4-fold increase in indole glucosinolates was observed for approximately 20% of the transgenic lines, whose appearance also resembled that of wild-type plants.13 The majority (approximately 80%) of the 35S CYP79B2 lines exhibited dwarfism, did not develop inflorescences, and, therefore, did not produce seeds. A possible explanation for this phenotype could be that the LAOX produced by CYP79B2 was partly channeled into production of the plant hormone IAA, which would disturb the growth and development of the plants. 

Yeast-based production of benzylisoquinolines represents a consistent and challenging continuation in the development of transgenic Saccharomyces for generation of complex plant-derived alkaloids [123]. In an ambitious approach, several yeast strains have been successfully designed containing for instance ... 

There are a number of examples of the development of plants for pharmaceutical protein production including antibodies, vaccines, and other bioactive proteins (Daniell et al., 2001 Daniell, 2006 Ma et al., 2005a, b, c Twyman et al., 2003) as well as consideration of the issues surrounding regulatory issues of the use of transgenic plants for pharmaceutical protein applications (Ma et al., 2005b Sparrow et al., 2007 Spok, 2007). 

One inhibiting factor in commercial development of transgenic oilseeds with novel traits is public acceptance. The primary principle upon which approval has been based is known as substantial equivalence, which means that aside from any introduced changes, the composition of the plant or seed remains essentially unchanged. However, the concept of unintended consequences expands the scope of substantial equivalence, which establishes criteria that must be examined and met. Satisfying the concern for unintended consequences broadened the concept of substantial equivalence to include transcripts, the proteome, metabolome, and even genome sameness (43). In the approval process for a transgenic plant, these issues become a key part of the risk assessment both for food crops (44) and for industrial crops (45). 

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