BIOCHEMISTRY ASSIGNMENT 2 Example | Topics and Well Written Essays - 500 words

BIOCHEMISTRY 2 - Assignment Example The process involves either an addition of a transforming group to one of the amino acids of the polypeptide chain or its proteolytic cleavage. The modifications comprise glycosylation, phosphorylation, nitrosylation, ubiquitination, acetylation, methylation, proteolysis lipidation. The process of PTM is governed by enzymes such as transferases, kinases, ligases and phosphatises which act upon distinctive amino acid side chains or on the peptide linkages. The mechanism of action of these enzymes involves addition or removal of distinct functional groups, sugars, lipids, proteins etc. either from or to the amino acid side chains. 1. During the process of translation (e.g. disulfide bonding). Disulfide bonds are formed between the two sulphur molecules. Amino acid Cysteine contains sulphur, as a result disulfide bond is formed between two residues of cysteine (R-S-S-R). The bond formed is strong and plays an imperative role in accurate folding as well as stability of protein molecules. DNA is the basic genetic material which is made up of four nucleotides Adenine (A), Guanine (G), Cytosine (C) and Thiamine (T). Adenine always pair with Thiamine with a double Hydrogen bond while Guanine pairs with Cytosine with a triple Hydrogen bond. The process of transcription is responsible for the formation of messenger RNA or mRNA. This process takes place inside the nucleus in eukaryotes. The sequence of nucleotides in DNA is responsible for the amino acid sequence of mRNAs which are translated into proteins. Transcription and translation involves the processes such as initiation, elongation and termination. The process of transcription involves RNA polymerase which is attached to the promoter sequence. When the protein is desired, the gene is â€Å"switched on† and when protein is not required the gene is â€Å"switched off†. Elongation is carried out after the assembly of PIC at the promoter site, TFIIH is similar to helicase which unwinds the DNA. Terminatio n