1.2ci - Protein Structure, Ligand Binding and Conformational Change Flashcards
(26 cards)
Proteins are polymers of…
amino acid monomers
Amino acids are linked by peptide bonds to form…
polypeptides
The chemical structure of a peptide bond involves…
two amino acids (OH and H) joining together to form water
Amino acids have the same basic structure, differing only in…
the R group present
The R groups of amino acids vary in…
size, shape, charge, hydrogen bonding capacity and chemical reactivity
Amino acids are classified according to their R groups:
basic (positively charged), acidic (negatively charged), polar, hydrophobic
Basic amino acids have which R group?
NH2
Acidic amino acids have which R group?
COOH
Polar amino acids have which R group?
OH
Hydrophobic amino acids have which R group?
Hydrocarbon
The wide variety of functions carried out by proteins results from…
the diversity of R grouups
The primary structure is…
the sequence in which amino acids are synthesised into the polypeptide
Hydrogen bonding along the backbone of the protein strand results in…
regions of secondary structure
Regions of secondary structure include…
alpha helixes, parallel or anti-parallel beta-pleated sheets, or turns
The polypeptide folds into…
a tertiary structure
The structure conformation is stabilised by…
interactions between R groups
Regions of tertiary structure include…
hydrophobic interactions, ionic bonds, London dispersion forces, hydrogen bonds, disulphide bridges
Disulphide bridges are…
covalent bonds between R groups containing sulphur
Quaternary structure exists in…
proteins with 2 or more connected polypeptide subunits
Quaternary structure describes…
the spatial arrangements of the subunits
A prosthetic group is…
a non-protein unit tightly bound to a protein and necessary for its function
The ability of haemoglobin to bind to oxygen is dependent upon the…
non-protein haem group
Interactions of the R groups can be influenced by…
temperature and pH
Increasing temperature disrupts the interactions that…
hold the protein in shape causing it to unfold and eventually become denatured
