3.6 Structure Of Proteins Flashcards
What are polypeptide made up of? What is their monomer?
Amino acids
What are proteins made up from
One or more polypeptide arranged as a macromolecule
What is the structure of amino acids?
H. H. AMINE GROUP
\/
N
|
R— C — H
|
C. CARBOXYL GROUP
//. \
O. O
|
H
Ami I acids can go through what two reactions?
Condensation and hydrolysis
What type of bond is formed between amino acids
Polypeptide bonds
Primary structure of protein
This is the sequence the amino acids are joined ( influence how the polypeptide folds and give the proteins final shape)-only peptide bonds
Secondary structure of protein
The oxygen, hydrogen and nitrogen atoms of the basic repeating structure of amino acids interact.Hydrogen bonds may form= coil shape= alpha helix
OR polypeptide chains lie parallel to one another joined by hydrogen bonds, forming a sheet-like structure (beta pleated sheet)
Tertiary structure of proteins
This is the folding of a protein into its final shape (often includes section of secondary structure).The coiling or folding of sections bring the R groups closer together so they can interact and create further folding of sections
Interaction occur between r groups in tertiary structure
.The R groups interactions - hydrophobic and hydrophilic( weak interaction between polar and non polar regions groups)
-hydrogen bonds- weakest bond formed
-ionic bonds - stronger than hydrogen bonds
-disulphide bonds- covalent - strongest bond
Quaternary structure of protein
Association of Two or more individual proteins (subunits)
Interactions are same as tertiary but are between different protein molecules rather than one
What enzyme break peptides?
Protease
Test for proteins
Liquid sample with equal volume of sodium hydroxide solution
Then few drops of copper surface solution until sample turned blue
Let solution sit for five minutes
What is the positive result for protein present
Purple
