Protein structure Flashcards
what is the structure of amino acids (names of groups)
carboxylic group (COOH)
Amine group (NH2)
N-C-C middle
residual group (R group)
always has hydrogen at the top (look at theory pack 1a)
what is the bond that is forms between dipeptides and polypeptides
peptide bond
formed between C and N = C-N
what is the reaction that joins amino acids together
condensation reaction
formed between carboxylic and amine group
what elements are amino acid made of
carbon
hydrogen
oxygen
nitrogen
what are the features of the primary structure (definition, bond formed, shape)
specific sequence of amino acids in a polypeptide chain
forms a peptide bond
linear
what are the two different structures that can be made in the secondary structure
alpha helix
beta pleated sheet
what are the features of the secondary structure (definition, bond formed, shape)
formed when amino acids interact to form either an alpha helix or a beta pleated sheet
hydrogen bonds formed (between -ve C=O and +ve N-H)
3D shape
what determines the shape of the amino acid in the secondary structure
hydrogen bonds
what are the features of the tertiary structure (definition, bonds formed, shape)
further folding of secondary structure into specific 3D shape
held together by bonds between amino acid R groups
bonds- ionic, hydrogen and disulphide bonds
3D shape
what are the features of the quaternary structure ( definition, bonds formed, shape
arrangement of more than one polypeptide chain
bonds- hydrogen, ionic, disulphide
3D shape
where is the polar R groups in a protein
found on the outside of a protein
why is the polar R group found on the outside of the protein
hydrophilic so is attracted to other polar molecules
active site is made of polar amino acids so is specific to polar substances
where is the non-polar R groups found in a protein
on the inside
why is the non-polar R group found on the inside of the protein
hydrophobic so repels polar molecules
stabilise protein structure and helps maintain its shape
why is the primary structure of a protein important in determining its 3D shape
sequence of amino acids in polypeptide determine position of R group
hydrogen disulphide an ionic bonds form between R groups
these bonds determine how polypeptide chain folds into 3D shape
specific 3D shape of protein gives protein specific properties allowing it to carry out different functions
