(Bio Mathematical Lab of Sikander Aqeel)
CHAPTER [3] PROTEINS
Proteins
(7/14/2016)
AMINO ACIDS ARE POLYMORIZED INTO PEPTIDE AND PROTEIN
The polymerized of the 20 amino acids into polypeptide chain within cell is catalyzed by enzymes and requires RNA and ribosome’s to occur chemically, the polymerized of amino acids into protein is a dehydration reaction,
The chemical rational of the reaction the a-carboxyl group of an amino acid chain R by the covalently joined to the a-NH2 group with side chain R2 by the elimination of molecule of water to form a type of amide bond known as the peptide bond,
The di-peptide (two amino acids residues joined by single peptide bond) can then form a second peptide bond through its terminal carboxylic acid group to the –a amino of third amino acid (R3) generating a Tri-peptide Repetition of this stepwise amino acids sequence (R1 – R2 – R3 – R4 …Ra)
The specific amino acids sequence of a natural polypeptide is determined form the genetic information,
The largest polypeptide chain in human are found in proto-collagen (a precursor of the structural protein collagen) and the contain approximately 1,200 amino acids residues per polypeptide chain, on the other end of the spectrum there are many small peptide with less than 10 amino acids, that perform important biochemical and physiological function in human being,
This paragraph is hard to understand about 1200 amino acids residues per polypeptide, to make easy I am explaining with the structure of the lipoproteins,
C3H4N1O2 + C4H4N1O2 = R2 = regular + peptide
|-H2O
C7H6N2O3 + C5H4N1O2 = R3 = Di-peptide
|-H2O
C12H8N2O4 = R4 - ...Ra = Tri-peptide
C3H4N1O2 + C4H4N1O2 = 87 + 99 = 186
C7H6N2O3 + C5H4N1O2 = 167.5 + 111 = 278.5
C12H8N2O4 = 246
LIPOPROTEINS
Apo-lipoproteins-B molecular weight = 800-300000
Number of amino acids = --
The a helix = 25 %
The B sheet = 37 %
The disordered = 37 %
ApoA-B
A. Tri-peptide
For example,
= a2 + b2 = c2
= a2 (Number amino acids) + b2 (Tri-peptide) = c2
= a2 (323.08) + b2 (C12H8N2O4) = c2
= a2 (323.08) + b2 (246) = c2
= a2 (104380.6864) + b2 (60516) = c2
= a + b = 164896.6864 = c2
= a + b = 164896.6864 / 45.25 (COOH) = 3644.12
= a + b = 3644
B. Water
= a2 / b2 = c2
= a2 (3644) / b2 (H2O) = c2
= a2 (3644) / b2 (18.25) = c2
= a2 (13278736) / b2 (333.0625) = c2
= a / b = 39868.60 = c2
= a / b = 39869 / 199.67 = 199.67
= a / b = 199.67 * 2.5 (H2= A//T DNA) = 499.175
= a / b = 499.175 * 3.75 (H3= C///G DNA) = 1871.90
= a / b = 1872 * 20 amino acids = 37440
= a / b = 37440 + 60 minute = 37500
= a / b = 37500 = Apo-lipoproteins-B
= a / b = 37500 * 8 = 300000
= a / b = 300000 / 8000 = 37.5 % B sheet
= a / b = 60 minute * 20 amino acids = 1200
= a / b = 1200 amino acids in Apo-lipoproteins-B protein
And they contain approximately 1,200 amino acids residues per polypeptide chain, so here 18 amino acids are balance of 67.87 minutes for take action, actually all amino acid contain on time, such as 1200 / 60 minutes = 20 amino acids, and one thing is more important here, that if amino acids number are less then protein take over time,