Hormones artificial synthesis

In addition to chemical-based drugs, a range of pharmaceutical substances (e.g. hormones and blood products) are produced by/extracted from biological sources. Such products, some major examples of which are listed in Table 1.2, may thus be described as products of biotechnology. In some instances, categorizing pharmaceuticals as products of biotechnology or chemical synthesis becomes somewhat artificial. For example, certain semi-synthetic antibiotics are produced by chemical modification of natural antibiotics produced by fermentation technology. 

Phenylalanine (Phe or F) (2-amino-3-phenyl-propanoic acid) is a neutral, aromatic amino acid with the formula HOOCCH(NH2)CH2C6H5. It is classified as nonpolar because of the hydrophobic nature of the benzyl side chain. Tyr and Phe play a significant role not only in protein structure but also as important precursors for thyroid and adrenocortical hormones as well as in the synthesis of neurotransmitters such as dopamine and noradrenaline. The genetic disorder phenylketonuria (PKU) is the inability to metabolize Phe. This is caused by a deficiency of phenylalanine hydroxylase with the result that there is an accumulation of Phe in body fluids. Individuals with this disorder are known as phenylketonurics and must abstain from consumption of Phe. A nonfood source of Phe is the artificial sweetener aspartame (L-aspartyl-L-phenylalanine methyl ester), which is metabolized by the body into several by-products including Phe. The side chain of Phe is immune from side reactions, but during catalytic hydrogenations the aromatic ring can be saturated and converted into a hexahydrophenylalanine residue. ... 

It has been noted in the case of several enzymes that their artificial prococious induction is reversible in that, unless the injection of the appropriate hormone is repeated, the enzyme disappears again. Why is it then that after its natural appearance at the scheduled time, the persistence of the enzyme does not hinge on the continued action of that hormone For example, glucocorticoid is undoubtedly the essential developmental stimulus for the hepatic ornithine aminotransferase(14), a member of the late suckling cluster. Its normal emergence on day 12 can be prevented by prior adrenalectomy, its precocious synthesis (5-10 days before schedule) can be evoked by an injection of cortisol, and yet no loss at all is incurred by adrenalectomy performed at or after the time at which ornithine aminotransferase has attained near adult or adult values (i.e. on day 20 or later). 

Joliot-Curie, Frederick. (1900-1958). A French physicist who, along with his wife Irene Joliot-Curie, won the Nobel Prize in chemistry in 1935. His important discoveries included artificial radioactivity. He did much work on atom structure, dematerialization of electrons, and inverse transformation. Work on hormone synthesis and thyroid substances containing radioactively labeled elements was significant. ScD from the University of Paris was followed by a distinguished career filled with honors and appointments. 

A pro-drug is a substance that has no special biological activity per se but can be converted into an active drug by enzymic action in the body. Thus, all the initial proteins formed by ribosomal synthesis that contain a peptide hormone structure locked within their amino-acid sequence are analogous to pro-drugs. The hormones are released by the action of proteolytic enzymes. Usually, however, the term prodrug is restricted to artificially synthesised molecules that are acted upon by the... 

In addition to the classical production of naturally occiuTing proteins, such as insulin, IFNs, growth hormone, growth factors and blood-clotting proteins, the techniques of molecular biotechnology enable the synthesis of superior proteins by synthesis of artificial genes or by directed evolution. 

Since 1962, Merrifield s new idea induced unanticipated activity in peptide chemistry around the world. The synthesis of artificial enzymes and hormones seemed to become possible, and hundreds of organic chemists and biochemists, as well as enzymologists and physicians, devoted themselves to the new method. Unfortunately the potential of the solid phase peptide synthesis was, from the very beginning, erroneously estimated by the international scientific public, both in a positive and negative sense. By emotional arguments more than by objective ones, the peptide chemists until recently were split into two parties, of which one trusted and the other condenmed the solid phase peptide synthesis. 

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