BCH4024 EXAM 1 QUESTIONS WITH
ALL ANSWERS REVISED
Absence of Vitamin C leads to unstable collagen, ---------and the hydroxyproline
stabilizes the collagen - Answer-scurvy
AT temperature of -------celsius, collagen with just proline will break down but will break
down at -------celsius if it has hydroxyproline - Answer-24, 58
The main driving force of protein folding is ----------- interaction - Answer-hydrophobic
------------are made of alpha and beta tubulin which requires other proteins to always fold
it - Answer-Microtubules
------------interactions create the platform for vander waals interaction - Answer-
Hydrophobic
Most of the noncovalent forces are ----------range forces measured in angstroms -
Answer-short
small proteins fold spontaneously in physiological ------- - Answer-salt
In electrostatic interactions, charges of the same sign means more energy is to be -------
---to hold charges together, vice versa for charges of different signs - Answer-supplied
which 4 AA's have anions - Answer-glutamate, aspartate, serine and threonine
which 3 AA's have cations - Answer-arginine-guanidine, lysine and histidine
Ionic bond also releases some ------, because the ions are often surrounded by water -
Answer-water
Vander waals operate over short distances, what is the formula F=---------, however
when they are apart the Force is ------------. Doubling distance reduces strength by 64 -
Answer-1/r^6, zero
Replacing one hydrophobic chain with another can greatly alter protein --------- -
Answer-stability
------------cations interaction cloud aromatic rings. It is basically when a cation is brought
close to an aromatic ring - Answer-Pi
,which three AA's form the pi cation bonding interaction - Answer-phenylalanine, tyrosine
and tryptophan
Which organic molecule binds to proteins through pi cation interactions, this bond is
fairly strong - Answer-acetylcholine
Protein folding is still a mystery, it involves --------------- (AA's just search for where they
will fit). If it happened in sequence the folding time would be really long - Answer-
massively parallel search
RNA folding which made the world is similar/dissimilar to protein folding - Answer-
similar
When we have a random polypeptide, the --------groups converge and then local bonds
interact, this is how proteins fold - Answer-apolar
Protein folding depends on three factors, ------- entropy from ordering proteins, a -------
entropy from intramolecular attractions and the -------- release of water - Answer-
unfavorable, favorable, favorable
The folding funnel can be though of as a reaction curve, where the bottom is the best
folded protein with a global ----------energy state - Answer-minimal
The loops on the side of the protein folding funnel shows when there where --------in the
folding process (kinetically controlled) - Answer-pauses
what three kinds of materials can denature proteins - Answer-organic solvents, urea and
detergents
who showed that the ribonuclease can be denatured and renatured- primary peptides
determines 3d model - Answer-Anfinsen
There are two different models of protein folding, the second one says that the
polypeptide ---------first then the secondary structure forms (second) into a --------- -
Answer-collapses, molten globule
There are two different models of protein folding, the first one says that the ----------
forms first (nucleation) - Answer-secondary structure
Some chaperones like the --------- use ATP to help proteins fold, the interior has both
apolar and polar parts - Answer-GROEL/GROES
Prusiner discovered ------- - Answer-scrapie
Biological information is processed almost exclusively by -------- interactions - Answer-
ligand biding
, In terms of ligand binding, biochemists prefer to use the dissociation version------------ -
Answer-P.L=P+L
High dissociation constant means ----- - Answer-low ligand affinity
The myo in myoglobin implies - Answer-muscle
Oxygen is poorly soluble in --------. And so organisms us very little spaced capillaries
and arteries to transport o2 to cells - Answer-water
RBC uses --------to transport o2 to tissues and CO2 to return to the lungs - Answer-
hemoglobin
O2 is stored in our tissues by -------------- (muscles) - Answer-myoglobin
RBC are not really -------, they do not have mitochondria, golgi, ER, glycolysis and
pentose phosphate pathway - Answer-cells
From weakest to strongest:
Hydrophobic interactions = Pi stacking = Van der Waals → Hydrogen bonds
=Electrostatic interactions → -----, the strongest apart from covalent bonds - Answer-
Salt bridge
Hydrophobic interactions are driven by -----------, ΔS, which
outweighs ----------, ΔH - Answer-entropy, enthalpy
Myoglobin and hemoglobin bind - Answer-o2
Myoglobin and hemoglobin have ----and ------ terminal (sticks out). heme is found in
both - Answer-N, C
The heme group is lodged between helices -----and ------ - Answer-E, F
Heme groups -------- each other and O2 binding behavior depends on ----------
interactions - Answer-do not touch, subunit
Heme groups have --------- pairs - Answer-alpha beta
Myoglobin is always a polymer/monomer - Answer-monomer
The structure of myoglobin and hemoglobin are very ---------, suggesting that they come
from a common ancestor and conservation of protein folding - Answer-similar
Hemoglobin is fully saturated at lung O2 pressure, ------ of the O2 are dumped to the
peripheral tissues. 1/3 returns to lungs - Answer-2/3
