problem set 8 Flashcards
LACKS conversion between IE and pH changes
NO chiral carbons
glycine
Two chiral carbons
isoleucine
threonine
at a pH of 9.7 alaine
-1
at a pH of 9.7 glutamic acid
-2
at a pH of 9.7
lysine
0
at a pH of 9.7
alanine, glutamic acid, lysine
-positive electrode-
move to the positive electrode
at a pH of 9.7
alanine, glutamic acid, lysine
-negative electrode-
none
at a pH of 9.7
alanine, glutamic acid, lysine
-don’t move-
lysine
pH 9 the protein would have a ____
negative charge
pH 4 it would have __
positive charge
proteins are least soluble
at their isoelectric point
when the isoelectric points are negative
they move to the positive electrode
changes in the pH most affect what type of bonding in proteins
ionic interactions (salt bridges)
polypeptides with few acid or basic side chain amino acids are less sensitive to pH changes than polypeptides with a higher number of side chains
the acid and basic side chains are in the salt bridge
polypeptides with few acid and basic side chains have very few salt bridges
thus they are not sensitive to pH change
what type of bonding is found in the primary structure of proteins
amide bond
amide bond is the same as a peptide linkage
what type of bonding is NOT found between protein chains in the quaternary structure
hydrophobic interactions
hydrophobic amino acid side chains are mostly found in the inside of a globular protein
hydrogen bonding of “O” in the amide and the “H from the nitrogen backbone
2
more than one polypeptide chain linked together
4
alpha helix
2
triple helix
4
slat bridges within a chain
3
hydrophobic interactions
3
disulfide bonding between chains
3
amino acid sequencing
1
