protein biotechno

..1st quiz...

only few hours b4 im leaving kuantan...a quiz and 2 class more...huh...what a life...

roughly this morning i gonna have protein biotechno quiz..which basically under protein structure topic...hehehe..sound simple only protein but its a bit worrin coz the topic is so familiar..n i might tend to be over confident..some of us yes...

but for me 50-50...huhuu...

protein basically consist of 20 type of amino acids that regularly can be found in all circulation...peptide bond that bing to one amino acid to anpther amino acid...in 2d pics...peptide bond can be found almost in planar shape...istead of that in 3d pic...the 2 or more bonded amino acids are in dihedral angle...while torsion angles where by all phi/psi chain, sheets, turns, side chain rotamers, is the key of protein folding... it can be seen through Ramachandran plot which roling to determine the type of secondary structure of protein level with reapect to the acceptable amount of phi / psi...

1. primary structure of protein...

its the order of amino acid themselves in linear polype[tide chain...

2. secondary structure of protein...

there r 2 types of it.. alpha helix n bete sheet which both of them r stabilised by the hydrogen bonding that form between of the main chain -CO n -NH group in amino acid in poltpetide chain...certain amino acids favour in helix or sheet or loop...motif are formed by packing the side chain from adjecent alpha helix and beta sheet strand..several motifs usually combaine n form compact globular structure called domains...loop doesnt have regular structure...

3. tertiary structure o protein...

its a result of assembling the secondary protein structure elements like motifs and domains...it refer to the sigle large polypeptide chain fold into several domeins...it stabalised by the hydroforbic forces but in the same time onic interaction n hydrogen bonding also play apart..the commonly motifs found include helix-loop-helix or HLH, Rossman fold, beta meander n BaB motif...other then that r simple motif combine to form complex motif such as Greek Key, Swiss or Jelly Roll...

4. quaternary structure of protein...

the highest level of protein structure..it association of two or more polypeptide chains, which each already fold in their tertiary structureto form multi subunits protein...its normally is a common feature for protein with complex function like transportation or gene expression...they r held together with disulphide bridge between different polypeptide chain...but many mutimeric protein comprise looser association of subunit stabilised by hydrogen bonding, hydrophobic effects or electrostatic interaction.....

hehehe..this some infos for protein structure...hopefully by writing this i can remember n manage to complete my quiz...wish me luck n do pray for me k...ehhheee....