OVERPRODUCTION STRATEGIES FOR MICROBIAL SECONDARY METABOLITES BASED ON METABOLIC ENGINEERING

metabolic engineering is advantageous in several aspects, compared to simple genetic engineering or ran.dom mutagenesis, since it allows defined engineering of the cell, thus avoiding unnecessary changes to the cell Many drugs and drug precursors found in natural organisms are rather difficult to synthesize chemically and to extract in large amounts. Metabolic engineering is playing an increasingly important role in the production of these drugs and drug precursors. This approach is typically achieved by establishing new metabolic pathways leading to the product formation, and enforcing or removing the existing metabolic pathways toward enhanced product formation. Recent advances in system biology and synthetic biology are allowing us to perform metabolic engineering at the whole cell level, thus enabling optimal design of a microorganism for the efficient production of drugs and drug precursors. Among the many successful examples of metabolic engineering, recent reports on the efficient production of L-valine, L-threonine, lycopene, antimalarial drug precursor. About lactic acid bacteria, several studies by metabolic engineering were carried out, that include production of exopolysaccharides, nitrogen metabolism, proteolysis and vitamin production

Keywords:

Secondary metabolites , Metabolic engineering , Microbial