Amino acids polypeptides and

PTH is the most important regulator of bone remodelling and calcium homeostasis. PTH is an 84-amino acid polypeptide and is secreted by the parathyroid glands in response to reductions in blood levels of ionised calcium. The primary physiological effect of PTH is to increase serum calcium. To this aim, PTH acts on the kidney to decrease urine calcium, increase mine phosphate, and increase the conversion of 25-OH-vitamin D to l,25-(OH)2-vitamin D. PTH acts on bone acutely to increase bone resorption and thus release skeletal calcium into the circulation. However, due to the coupling of bone resorption and bone formation, the longer-term effect of increased PTH secretion is to increase both bone resorption and bone formation. 

Sela, M., Synthetic antigens and recent progi ss in immunology, in Peptides. Polypeptides and Proteins. Proceedings of the Rehovot Symposium on Poly (Amino Acids), Polypeptides and Proteins, John Wiley and sons, New York, 1974, pp. 495-509... 

Papain is a cysteine protease isolated from the latex of the immature fruit and leaves of the plant Carica papaya. It consists of a single 23.4 kDa, 212 amino acid polypeptide, and the purified enzyme exhibits broad proteolytic activity. Although it can be used as a debriding agent, it is also used for a variety of other industrial processes, including meat tenderizing and for the clarification of beverages. 

Theoretically, any number of solutes can be separated in this manner and the method has been applied, for example, to the separation of fatty acids, amino acids, polypeptides and other biological materials with distribution... 

Infrared Analysis of the Structure of Amino Acids, Polypeptides, and Proteins... 

Infrared analysis of the structure of amino acids, polypeptides and proteins. Advanc. Protein. Chem. 7, 291—318 (1952). 

Theoretically, any number of solutes can be separated in this manner and the method has been applied, for example, to the separation of fatty acids, amino acids, polypeptides and other biological materials with distribution ratios in some cases differing by less than 0.1. However, the procedure can be lengthy and consumes large volumes of solvents. It is frequently more convenient to use one of the chromatographic techniques described later in this chapter. These can be considered as a development of the principle of countercurrent distribution. 

Noguchi, I., and Saito, T. Poly(amino acids), polypeptides and proteins (ed. M. A. Stah-maim),p. 313. Univ. of Wiscon Press 1962. 

Structural Studies of Amino Acids, Polypeptides and Proteins in the SoUd State by CRAMPS NMR... 

A study example concerning the solid structure of a-amino acid, polypeptide and a protein is given to introduce the basis of the chemical shift of proton NMR precisely, and studies to do this have only recently been undertaken. Some interesting work has been done, including the discrimination of amino acid crystal polymorphism, conformational analysis of polypeptides and fibrous proteins, and the determination of the N—H bond length in polypeptides. 

We introduce research results from recent proton Combined Rotation and Multiple Pulse Spectroscopy (CRAMPS) NMR of a-amino acids, polypeptides and proteins. Proton CRAMPS NMR research has only just begun and has the possibility of wide-ranging future development. 

Among the soluble forms of Cu present in natural waters the following are to be taken into consideration carbonate complexes [CuC03(aq)] and [Cu(C03)2], and hydroxo complexes [CuOH]" , [Cu(OH)3] and [Cu(OH)4]. Important complex-forming substances are polyphosphates which can bond copper into stable chelate structures. Silicates, sulphates and nitrates do not form complexes with copper. Of the organic complexes, production of compounds with amino acids, polypeptides and humic substances are of interest. 

A number of enzymes have been obtained in highly purified form, even crystalline, and their chemical and physical properties have been extensively studied. In general, enzymes operate most efficiently in aqueous media. All enzymes are macromolecules, with molecular weights ranging from about 10" to 10. More precisely, a portion of all enzymes is protein in nature. Proteins are polymers of a-amino acids (polypeptides) and have the general formula... 

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