Sikander Aqeel

BIO ALGEBRA OF LIVING ORGANISMS

Apr 16th 2016, 11:09 am

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(Bio Mathematical Lab of Sikander Aqeel)

CHAPTER [3] PROTEINS

Proteins

(4/17/2016)

Amino Acid Composition of Proteins:

It is amazing that all the different types of proteins are initially synthesized as polymers of only 20 amino acids, known as the common amino acids, the common amino acids are defined as those amino acids for which a specific codon exists in the DNA genetic code, there are 20 amino acids for which DNA codon are known, the process of the reading of the DNA code, resulting in the polymerization of amino acids of a specific sequence into the proteins based on the DNA code, In this chapter we shall discus only the protein of this genetically controlled synthetic process,

In addition to the common amino acids, derived amino acids are found in proteins, derived amino acids are found from one of the common amino acids, usually by an enzyme-facilitated reaction, after the common amino acids has been incorporated into the proteins structure, an example of a derived amino acids Cystine, other derived amino acids are desmosine and isodesmosine found in protein elastin,

The hydroxyproline and hydroxylysine found in Collagen and Y-carboxyglutamate found in prothrombin,

Regular Structure of the Common Amino Acids,

The common amino acids have the regular structure, they contain on common a central (Alpha) carbon atom, to which a carboxyl acid group an amino group, and a hydrogen atom are covalently bonded, the (Alpha) a-carbon atom binds a side chain group designated R, that is different for each of the 20 amino acids,

COO-

NH3 – C – H Regular structure of common amino acids,

In the structure the ionized form for a common amino acids that present in solution at 7.0 pH is shown,

For example,

= a2 + b2 = c2

= a2 (NH3) + b2 (H) = c2

= a2 (17.75) + b2 (1.25) = c2

= a2 (315.0625) + b2 (1.5625) = c2

= a + b = 316.625 = c2

= a + b = 316.625 / 44 (COO-) = 7.19

= a + b = 7 = pH

Glycine