Prepared by: Pritesh radadiya ( ) Hardik amipara ( ) Kaushik padsala ( ) Nishant dobariya( ) Guided by: Dr. parin kanaiya

2 Proteins are linear copolymers built from monomeric units called amino acids. Twenty amino acids are commonly found in proteins. These amino acids contain a variety of different functional groups: –Alcohols(R-OH) –Phenols(Ph-OH) –Carboxylic acids(R-COOH) –Thiols(R-SH) –Amines(R-NH 2 ) –and others…

3 To understand protein function, we must first understand the nature of amino acids. Amino acids are essentially α-amino acids: alpha carbon (IUPAC #2 position) H 2 N – C – COOH | R When R is not H, the alpha carbon is asymetric, giving rise to isomers.

4 PROTEIN

COMPOSITION The proteins are polymers made of monomers called the amino acids. There are 20 different kinds of amino acids that make up the proteins. However, they are present in different proportions in each of the proteins. The proteins are nothing but the arranged chain of the monomers which called a “peptide” and its make a protein. 5

6 Primary (1°) Protein Structure –linear sequence of amino acids. Secondary (2°) Protein Structure –localized regional structures Teritary (3°) Protein Structure –overal shape of proteins Quaternary (4°) Protein Structure –interactions between proteins CLASSIFICATION

PRIMARY STRUCTURE 7 The primary structure of a protein refers to the linear sequence of amino acids in the polypeptide chain. The primary structure is held together by covalent bonds such as peptide bonds, which are made during the process of protein biosynthesis or translation. The two ends of the polypeptide chain are referred to as the carboxyl terminus (C-terminus) and the amino terminus (N-terminus) based on the nature of the free group on each extremity

8

SECONDARY STRUCTURE 9 Secondary structure refers to highly regular local sub-structures on the actual polypeptide backbone chain. Two main types of secondary structure, the alpha helix and the beta strand or beta sheets, were suggested in 1951 by Linus Pauling and co workers. These secondary structures are defined by patterns of hydrogen bonds between the main- chain peptide groups.

10

TERTIARY STRUCTURE 11 Tertiary structure refers to the three-dimensional structure of monomeric and multimeric protein molecules. The alpha-helixes and beta pleated-sheets are folded into a compact globular structure. The folding is driven by the non-specific hydrophobic interactions, the burial of hydrophobic residues from water, but the structure is stable only when the parts of a protein domain are locked into place by specific tertiary interactions.

12

QUATERNARY STRUCTURE 13 Quaternary structure is the three-dimensional structure of a multi-subunit protein and how the subunits fit together. In this context, the quaternary structure is stabilized by the same non-covalent interactions and disulfide bonds as the tertiary structure. Complexes of two or more polypeptides (i.e. multiple subunits) are called multimers. Specifically it would be called a dimer if it contains two subunits, a trimer if it contains three subunits.

14

15 ISOLATION OF PROTEIN Protein purification is a series of processes intended to isolate one or a few protein from a complex mixture, usually cells, tissues or whole organisms. Protein purification is vital for the characterization of the function, structure and interactions of the protein of interest. The purification process may separate the protein and non-protein parts of the mixture, and finally separate the desired protein from all other proteins.

16 QUALITATIVE TEST OF PROTEIN 1.Xanthoproteic test 2.Biuret test 3.Ninhydrin test 4.Millon’s test 5.Hopkins cole test

17 AMINO ACID

18 CLASSIFICATION The classification of amino acid base on following types 1. According to reactive group or R group 2. Dependent in the property of R group 3.Dependent according to polarity of R group

19 According to reactive group Aliphatic,Aromatic,OH, Acidic,Acid amide, Sulphur,Cyclic Dependent in the property of R group Non polar or Hydrophobic,Polar uncharged,Polar charged,Positively charged,Negatively charged

20 1. Non-Polar -- 8 Amino Acids Hydrocarbon,Aromatic, Thiol Ether 2. Flexible -- 1 Amino Acids Gly 3. Polar Amino Acids Alcohol,Thiol,Amides,Acids,Bases Dependent according to polarity of R group

21 SYNTHESIS OF AMINO ACID Amino acid synthesis is the set of biochemical processes by which the various amino acids are produced from other compounds. The substrates for these processes are various compounds in the organism's diet or growth media. Not all organisms are able to synthesise all amino acids. Humans are excellent example of this, since humans can only synthesise 11 of the 20 standard amino acids, and in time of accelerated growth, arginine, can be considered an essential amino acid

22 THNK YOU