Since the day, man has tried to imitate and understand everything that nature does, from fire to electricity and even the production of diamonds and so far scientists have been quite successful, many physicists and chemical processes can be reproduced in vitro by scientists, but the biological field is lagging slightly behind and there is still much to learn about enzyme-facilitated reactions and the different metabolites. Say no to plagiarism. Get a tailor-made essay on 'Why violent video games should not be banned'? Get the original essay Secondary metabolites are particularly interesting because they are usually unique to a particular species - for example, the humble poppy produces the alkaloid clinically known as morphine, and generally have no proven effect on the organism that makes the chemical, but could have an effect on potential predators. Secondary metabolites are biosynthesized from a small number of important compounds arising from reactions that produce or metabolize essential metabolites such as proteins, carbohydrates, and nucleic acids, with particular attention to acetate and acid. mevalonic. Each compound having its own reaction pathway, the polyketide pathway involves acetate in the thioate form with a coenzyme A leaving group, the mevalonic acid pathway has mevalonic acid as a precursor as the name suggests however it is biosynthesized from 3 units of CH3CO2H. .In this article, the biosynthesis of secondary metabolites of the polyketide and mevalonic acid pathways will be discussed along with the biological activity of the metabolites.PolyketidesBiosynthesis is the formation of chemical compounds by living beings, usually in cells, l acetate being the precursor of the polyketide pathway. and the source of mevalonic acid is obtained from metabolized fatty acids. Polyketides are structurally diverse and typically contain alternating oxygen atoms that derive from the carbonyl groups of fatty acid precursors. They are the most common fungal secondary metabolite and are formed via the polyketide pathway. , these substances possess a range of medicinal activities from antibiotics, antifungals and anticancer compounds, the variety of these substances corresponds to the variety of biosynthesis mechanisms, the enzymology of many polyketide synthases is different from each other and only three were known in 1985: 6-methylsalacilic acid synthase from Penicillium patulum, naringenin chalcone synthase from the parsley plant Petroselinum hortense and resveratrol synthase from the peanut plant Arachis hypogaea. These three enzymes were studied and shown to have the fundamental characteristics of a polyketide synthase, but to have markedly varied properties, but did not lead to a consistent prediction of how a bacterial polyketide synthase would be organized, largely because of the contrast in function and size of bacterial polyketide synthase. functional enzymes, for example 6-methylsalecilic acid, had a molecular mass of 800,000 Da, it is suggested that its structure was due to its role as a tetrameric protein with multiple functions, to which all substrates are covalently linked , unlike charcone synthase, a homodimer whose units have a molecular mass of only 42,000 Da and act on CoA esters of substrates and are unable to mimic the action of an acyl carrier protein. This leads to further research into derivatives of the polyketide pathway. The formation of a polyketide begins with the.!