Disease studies and primary structure of proteins
Answers
Answer:
Proteins are molecular devices, in the nanometer scale, where biological function is exerted (1). They are the building blocks of all cells in our bodies and in all living creatures of all kingdoms. Although the information necessary for life to go on is encoded by the DNA molecule, the dynamic process of life maintenance, replication, defense and reproduction are carried out by proteins.
There are twenty natural amino acids, whose frequency is higher than other special ones with particular functions. These twenty amino acids can be grouped together forming polypeptide chains, or proteins, in different ways determined by the genetic code and limited by stereochemical properties. These proteins may have a constitutive or transient cell expression in regard to its functions. It is worth mentioning that efforts are underway to make proteins of unnatural amino acids as well
Explanation:
3.1 Primary structure
The primary structure of a protein originally referred to its complete covalent structure but is more frequently interpreted as being the sequence of amino acids of each polypeptide chain of which the protein is composed. These are often one and the same thing but disulphide bonds and other rarer types of covalent bond formed between amino acid side chains are not directly encoded by the sequence itself.
A polypeptide chain is a unidimensional heteropolymer composed of amino acid residues. There are basically only twenty naturally occurring amino acids which are directly encoded by the corresponding gene, although in exceptional cases stop codons can be used for the incorporation of two additional amino acids (selenocysteine and pyrrolysine (32)). All of these amino acids are α-amino acids which possess the generic structure given in Figure 3a. Common to all such amino acids is the amino group, carboxylic acid group and hydrogen bound to the central carbon atom (the α carbon). Only the R group (also known as the side chain) differs from one amino acid to another and it varies in terms of size, polarity, hydrophobicity, charge, shape, volume etc. With the twenty different amino acids available, nature is able to produce the wide diversity of functions which proteins perform in living organisms.
Diseases.
The proteopathies (also known as proteinopathies, protein conformational disorders, or protein misfolding diseases) include such diseases as Creutzfeldt–Jakob disease and other prion diseases, Alzheimer's disease, Parkinson's disease, amyloidosis, Multiple System Atrophy, and a wide range of other disorders
