Bio Proteins

protein's function depends on its' structure which consists of chains of amino acids that twist and fold into a very complex shape

• contain a carboxyl group, amine group and one of 20 different side chains (R group)
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• hydrophobic
• hydrophilic
• acidic
• base

a bond between the amine group of one amino acid and the carboxyl group of another

chain of amino acids linked by peptide bonds

polypeptide formation

• primary structure (polypeptide formation) - linear sequence of amino acids
• 
• secondary structure - hydrogen bonds along the polypeptide backbone twist the polypeptide into a coil or sheet
• 
• tertiary structure - bonds between side chains give the polypeptide its overall 3D structure
• 
• quaternary structure - in some proteins, two or more polypeptide chains associate and function as one molecule (like hemoglobin)
• 

• to unravel the shape of a protein or other large biological molecule
• changes in a protein's structure may also alter its' function

recognize infectious agents and change structure