Predict the elution order (i.e. order they flow off
the column) of the following proteins from a Sephadex G100 size exclusion column:
Bovine Carbonic anhydrase 31 Kd,
BSA = 66 Kd,;
Egg albumin = 45 Kd,,
Rabbit skeletal muscle myosin = 200 Kd,.
Rabbit skeletal muscle myosin (1st) (200kD),
BSA (2nd), (66kD)
Egg albumin (3rd) (45kD),
Bovine Carbonic anhydrase(4th) (31kD).
Anion exchange chromatography of proteins involves:
A) Separation based on the native or
natural charge of the protein .
B) Competition with a negative
counter-ion associated with the exchange resin.
C) The use of DEAE (diethyl amino ethyl)
exchange resins.
D) Elution of proteins with increasing
concentrations of salt.
E) All of the above
E. ALL THE ABOVE
Nickel His affinity purification has
two limitations, name them.
A) The need to engineer a polyhistidine
tag into the protein sequence.
B) The histidine tag must be exposed on
the surface.
Dialysis
involves _______________________.
Removal of ions via diffusion through a semi-permeable membrane.
TRUE OR FALSE?
Enzymes are not capable of catalyzing +(Delta) G reactions
True.
Which letter most likely indicates the product?
E
Enzymes often utilize non-protein molecules to
function, which are termed ------.
COFACTORS
Lyases mainly involve -----------?
A group that is removed by elimination to form double bonds
In the double reciprocal plot the vertical intercept (y-intercept) is equal to------.
1/VMAX
CONSTRUCT AN EPIMER OF THIS COMPOUND:
This monosaccharide is termed?
furanose
WHAT THE HELL IS WRONG WITH THIS?
Cu+2 is oxidized
In the polysaccharide glycogen, large numbers of
monosaccharides are linked together
through------. NAME 2
A) Glycosidic linkage
B) Anomoric carbons
In ketose sugars, ring formation can occur because the ketone group reacts reversibly
with a hydroxyl group in an aqueous solution. This process is termed _______.
Mutorotation.
Cis double bonds exist in:
A) Omega 3-fatty acids
B) Delta 9 fatty acids
C) Unsaturated fatty acids
ALL OF THEM.
Arachidonic acid is the precursor for the formation of:
A) Prostaglandins
B) Thromboxanes
C) Ecosanoids
ALL OF THEM
Patients with familial hypercholesterolemia-------.
Have missing or defective LDL receptors
The inability to breakdown--------- is the basis of Tay Sachs disease.
Gangliosides
The following molecule is:
A) Comprised of terpene subnits
B) Considered a mixed terpenoid.
C) A precursor for vitamin A
ALL OF THEM
REVIEW 21 FROM THE TEST. JUST TOO BIG FOR A FLASH CARD. BE ABLE TO READ A 2D GEL.
MW IS Y AXIS AND pI IS ON THE X AXIS.
TO FIND AN UNKNOW DIVIDE Ve/Vo AND PLOT IT.
Briefly describe the two main reasons why SDS is used in SDS-PAGE.
Denatures protein.
Provides negative charge that obliterates the native protein charge. Protein moves under influence of electric field with a constant charge to mass/ratio.
Define the following terms: activation energy, coenzyme, and active site.
Activation energy-- This energy state must be reached for a chemical reaction to occur (i.e. colliding molecules possess a minimal amount of energy). Or the free energy of activation (delta G double dagger)--energy barrier at the transition state.
Coenzyme- small organic molecule associated with the enzyme and necessary for this enzyme to function.
Active site- site on enzyme where interaction with a substrate occurs.
In the following Michaelis Menten plot, describe what type of inhibition is displayed.
Competitive –same Vmax, different Km
Ultimately, (a) how do enzymes lower activation energy and (b) describe what is meant by the term “catalytic perfection.”
(a) The shape and charge of the active site forces the substrate to adopt a conformation more like the transition state. As a result, the enzyme substrate complex converts to product and free enzyme without the high energy requirement needed to achieve the transition state in the absence of the enzyme.
(b) enzyme functioning at its diffusion controlled limit or as fast a substrate can diffuse and interact with the enzyme (getting the most bang for the buck!)
Name the type of linkage present, specifically numbering (label on structure) the carbons forming this linkage. alpha or beta form?
BETA FORM WITH 1-4 BETA LINKAGE.
Describe why Sucrose can not be considered a reducing sugar.
Both anomeric carbons are bound in linkages (alpha, beta 1,2 linkage) and thus cannot react.
What is the common name of the disaccharide formed from one molecule of galactose linked to one molecule of glucose in a beta (1,4) linkage?
LACTOSE
Draw the structure of galactose in the ring closed, Haworth projection.
Carbohydrates linked via asparagine or serine are termed----- and------bonds, respectively.
N-LINKED
O-LINKED
Trans fats are considered harmful to humans. Describe how trans fats are synthetically formed.
Via hydrogenation of unsaturated double bonds in fatty acids.
Draw the triacylglycerol formed from
3 molecules of Myristic acid, formula
(14:0)
The specific ecosanoids --------- are most commonly involved in anaphylactic shock while ---------- are involved in platelet aggregation.
leukotrienes
thromboxanes
Although high cholesterol levels may be detrimental, it is a necessary cellular component. Specifically, describe the role of cholesterol in membrane structure.
Membrane rigidity, inserts between fatty acid tails
NAME THIS MONOSACCHARIDE, WHAT FORM D OR L?
D-RIBOSE.
NAME THIS MONOSACCHARIDE, WHAT FORM D OR L?
D-GLUCOSE
DRAW A HAWORTH PROJECTION FOR THIS MONOSACCHARIDE:
D-GLUCOSE IN A FORM. FOR B FORM FLIP THE OH ON NUMBER 1 UP.
DEFINE HDL
High density lipoprotein-scavenges extra cholesterol.
Considered “good” when elevated.
DEFEINE LDL
Low density lipoprotein-transfers cholesterol to tissues.
Considered “bad” when elevated.
Label and give an example of the class of molecule below:
Class = Wax.
Example = Beeswax or Carnuba
Indicate the omega and delta designation of double bonds in the following 18 carbon fatty acid, include all double bonds in the omega nomenclature.
Omega 3,6,9
Delta 9,12,15
Label the type of linkage in (a) and (b), respectively be specific!
a =alpha 1,6
b= alpha 1,4
Glucose
Describe why aspirin is often taken during the first signs of a heart.
Prevents platelet aggregation by limiting production of thromboxanes and reduces inflammation by limiting production of prostaglandins (conversion of arachidonic acids)
