proteins - biochemistry

amino acids

• proteins are made of AMINO ACIDS

• each amino acid is a 2 carbon long structure with an AMINE & CARBOXYL functional groups

• link together using CONDENSATION REACTION for amine group to carboxyl group → called a ‘peptide bond’

• 2 amino acid sequence based → called a dipeptide

• 3 long amino acid → tripetide

primary structure

• basic amino acid sequence

• based on covalent

secondary structure

folding pattern

• alpha helices

• beta sheets

• electrostatic attractions

• hydrogen bonds

tertiary structure

overall folding pattern of whole polypeptide

• electrostatic attractions

• hydrogen bonds

• disulfide bridge

quaternary structure

once folded, two or more polypeptides link together

prosthetic groups

non protein complexes that are attached to the protein to make the protein function

protein denaturation process

• an egg is made up of protein called ALBUMIN

• when egg is raw, the albumin is clear and runny

• once heated, albumin changes to solid white

• still a protein but no longer has the same function

four types of amino acids by r-group

• non-polar (hydrophobic)

• polar (hydrophilic)

• acidic (negative charge)

• basic (positive charge)

protein folding

driven by hydrogen bonds, ionic bonds, hydriphobic interactions, disulfide bridges

proper folding

functional protein

misfolding

loss of function → can cause disease (ex: alhiemers)