Industrial Biotechnology Essay Example | Topics and Well Written Essays - 2000 words

Industrial Biotechnology - Essay Example Transgenic plants, like Bt corn and herbicide resistant soybeans, were designed to improve agronomic performance, although these are also used in biopharming (pharmaceuticals from plants). Transgenic animals are currently used to express drugs in milk. Biotechnological approaches have been used to enhance the yield and diversity of the important compounds amino acids, vitamins, antibiotics and biofuels. Amino acids Amino acids are the building blocks of proteins. Humans and animals alike can synthesize amino acids, except for eight that have to be supplemented by the diet. Aside from their roles in nutrition, amino acids are also used as food flavour enhancers, for medical uses such as transfusion of proteinaceous food and ammonia detoxification, and in the manufacture of synthetic raw materials in the chemical industry (Okafor, 2007). Globally, glutamic acid, lysine and methionine are produced in the highest amounts, although all amino acids can be and are being synthesized. The fla vour enhancer monosodium glutamate is the number one product in terms of tonnage (Demain, 2007). Okafor (2007) reviewed the different methods used to manufacture amino acids. Hydrolysis of high protein products like hair, keratin and feathers is the oldest means of manufacturing amino acids. However, this procedure is highly dependent on the amount of raw material that is available. Amino acids are also chemically synthesized, but the end-products are a mixture of D and L forms which necessitate an additional expensive step to produce the biologically active L-form. Fermentation of carbon and nitrogen materials through the action of different bacterial species is the most economical and feasible to large-scale process. Enzymatic process converts specific substrates to amino acids through specific enzyme catalysis. The most important method for microbiological production of amino acids is through direct fermentation and this is where biotechnological approaches have been utilized the most. The discovery that microorganisms like bacteria, moulds and yeast express amino acids was the stimulus for advancement in this field. Corynebacterium, Brevibacterium, Microbacterium and Arthrobacter are the most common bacterial genera employed for direct fermentation. To induce expression of amino acids, media and culture conditions are modified. However, bacteria will produce the amino acids only to a certain extent because they have this innate control of production to prevent toxic effects. Thus, bacteria have been engineered that do not have the control mechanisms for inhibiting amino acid production. Auxotrophic mutants have increased production of L-glutamic acid (Nakamura, et al., 2007; Asakura, et al., 2007). Regulatory mutants for amino acid production have also been developed. These mutants possess an enzyme that is insensitive to feedback inhibition, and thus continues to overproduce a certain amino acid. For example the bacterium Brevibacterium flavum was enginee red to be insensitive to increased lysine concentration which has an inhibitory effect on aspartate kinase activity (Fernandez-Gonzalez, et al., 1996). Aspartate kinase is the only system in the lysine biosynthesis pathway that is sensitive to increased lysine levels. Recombinant DNA technology has greatly enhanced the introduction of genes into current