Download Electrophoretic Properties of Native Proteins

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Edvo-Kit #111
111
Electrophoretic Properties
of Native Proteins
Experiment Objective:
The objective of this experiment is to develop a general understanding of
the structure and electrophoretic migration of native proteins.
See page 3 for storage instructions.
111.051128
EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Table of Contents
Page
Experiment Components
Experiment Requirements
3
3
Background Information
Electrophoretic Properties of Native Proteins
4
Experiment Procedures
Experiment Overview
Preparations for Agarose Gel Electrophoresis
Practice Gel Loading
Conducting Agarose Gel Electrophoresis
Staining the Gel
Study Questions
7
8
11
12
13
14
Instructor's Guidelines
Pre-Lab Preparations
Quick Reference Tables
Avoiding Common Pitfalls
Expected Results
Answers to Study Questions
15
16
17
18
19
20
Safety Data Sheets can be found on our website: www.edvotek.com/safety-data-sheets
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Experiment Components
A
B
C
D
E
Bovine Serum Albumin (BSA)
Ovalbumin
Cytochrome C
Lysozyme
Horse Serum Proteins
•
•
•
•
•
•
•
Practice Gel Loading Solution
UltraSpec-Agarose™ Powder
50x Electrophoresis Buffer
Protein InstaStain® Sheets
1 ml Pipet
100 ml Graduated Cylinder (packaging for samples)
Microtipped Transfer Pipets
Store Components A-E at 4°C.
This experiment contains ready-to-load
protein samples and reagents sufficient for
6 gels (see Quick Reference).
Quick Reference:
There is enough sample for 6 gels if you
are using an automatic micropipet for
sample delivery. Use of transfer pipets
will yield fewer gels.
Requirements
•
•
•
•
•
•
•
•
•
•
•
•
Horizontal Gel Electrophoresis Apparatus
D.C. Power Supply
Automatic Micropipets with Tips
Waterbath
Recommended Equipment:
Visualization System (white light)
Glass Staining Tray
250 ml Flasks
Pipet Pump
Hot Gloves
Marking Pens
Distilled or Deionized Water
Methanol
Glacial Acetic Acid
All components are intended for educational research only. They are not to be used for diagnostic or drug purposes, nor administered
to or consumed by humans or animals.
UltraSpec-Agarose and Protein Plus are trademarks of EDVOTEK, Inc.
Protein InstaStain, EDVOTEK, and The Biotechnology Education Company are registered trademarks of EDVOTEK, Inc.
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111.051128
3
EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Background Information
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Proteins are a highly diversified class of biomolecules. Differences in their chemical properties, such as charge,
shape, size and solubility, enable them to perform many biological functions. These functions include enzyme
catalysis, metabolic regulation, binding and transport of small molecules, gene regulation, immunological defense
and cell structure.
A protein can have a net negative or positive charge, depending on its amino acid composition and pH conditions.
At a certain pH, the molecule can be electrically neutral, i.e. negative and positive charges are equal. In this case,
the protein is isoelectric. In the presence of an electrical field, a protein with a net negative or positive charge will
migrate towards the electrode of opposite charge. The amino acid residues responsible for a protein’s negative
charge at physiological pH are glutamic acid and aspartic acid. A protein’s positive charge at physiological pH is due
to lysine, arginine and, to a lesser extent, histidine.
N-Terminal
H+
|
H-N-H
H+
|
H-N-H
H+
|
H-N-H
O
O
CH2- CH2- C
Glutamic
Acid
Lysine
O
CH2- CH2- C
CH2- CH2- C
OH
OH
H
| +
CH2- CH2- CH2- CH2- N - H
|
H
H
| +
CH2- CH2- CH2- CH2- N - H
|
H
C
H
|
CH2- CH2- CH2- CH2- N
|
H
C
C-Terminal O
O
C
O
O -
HO
Acidic pH
(<4)
OH
Neutral pH
(7)
O -
Alkaline pH
(>9)
Figure 1:
Effect of pH on Peptide Containing Glutamic and Lysine Residues
At acidic pH, glutamic acid and aspartic acid residues have little charge, while lysine and arginine both have positive charges. As the pH of the protein solution is raised, glutamic and aspartic acid release a proton and become
negatively charged. However, lysine and arginine residues become uncharged as the pH is raised to high values.
(See Figure 1.)
The direction and extent of a protein’s migration in an electric field can be altered by using an acidic, neutral or alkaline buffer system during electrophoresis. The isoelectric point of a protein is defined as the pH at which the protein has no net charge. Consequently, a protein will not migrate in an electric field at its (pI) isoelectric point. An
isoelectric protein still possesses areas of negative and positive charge, but overall they cancel each other. Proteins
that contain more aspartic and glutamic acid residues will have isoelectric points at acidic pH values. Conversely,
proteins that contain more lysine and arginine residues will have isoelectric points at alkaline pH values.
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ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Background Information, continued
Some proteins contain other chemical groups in addition to their amino acid residues. For example, hemoglobin
and cytochrome c contain heme, which consists of iron complexed to a system of organic rings called porphyrin.
“Non-amino acid” structural groups covalently attached or very tightly bound to the polypeptide chain(s) of a
protein are called prosthetic groups. Prosthetic groups enable proteins to perform biological functions and have a
strong influence on the protein’s chemical properties. The oxygen atoms transported by hemoglobin are actually
bound at the heme irons.
Proteins exhibit many different three-dimensional shapes and complex folding patterns which are determined by
their amino acid sequence and post translational processing such as adding carbohydrate residues or prosthetic
groups. The precise three-dimensional configuration of a protein is critical to its biological function. The general
shapes for proteins are spherical, elliptical or rod-like. The molecular weight is a function of the number and
type of amino acids in the polypeptide chain. Proteins can consist of a single polypeptide or several polypeptides
specifically associated with each other. These polypeptides can be identical, similar or completely different from
one another. The number and nature of polypeptides in a protein has large effects on its mass, size and shape.
Proteins that are in their normal, biologically active forms are called native. Certain detergents, extremes of pH,
organic solvents and heat can cause a native protein to lose its specific three-dimensional folding pattern and,
consequently, its biological activity. Proteins that have gone through this process are called denatured. Denatured
proteins can have radically different behavior from their native forms during electrophoresis.
ELECTROPHORESIS OF PROTEINS
The properties of proteins affect the way they migrate during gel electrophoresis. Gels used in electrophoresis
(e.g. agarose, polyacrylamide) consist of microscopic pores of a defined size range that act as a molecular sieve.
Only molecules with net charge will migrate through the gel when it is in an electric field. Small molecules pass
through the pores more easily than large ones. Molecules having more charge than others of the same shape and
size will migrate faster. Molecules of the same mass and charge can have different shapes. In this case, those
with a more compact shape, like a sphere, will migrate through the gel more rapidly than those with an elongated
shape, like a rod. In summary, the amount and sign of charge, the size and shape of a native protein, all affect its
electrophoretic migration rates.
Electrophoresis of native proteins is useful in clinical and immunological analysis of complex biological samples,
such as serum. Serum consists of many different types of proteins. Gel electrophoresis of native serum proteins
at alkaline pH results in several zones. Albumin is by far the most abundant serum protein and has one of the
fastest electrophoretic migration rates. Albumin binds and transports many small molecules, including fatty acids
and bilirubin. It is also involved with osmotic regulation. The serum proteins with the slowest migration rates are
the gamma globulins (antibodies). In between these two zones several other types of proteins can be observed.
These include transferrin (iron transport), ceruloplasmin (copper transport), macroglobulin (protease inhibitor) and
haptoglobin (involved with the binding and conservation of hemoglobin). Electrophoretic patterns of human serum
proteins can aid in the diagnosis of certain diseases. For instance, cirrhosis of the liver causes a decrease in albumin, while multiple myeloma ( a cancer of the immune system) and chronic rheumatoid arthritis causes abnormal
increases in the gamma globulins.
The purified proteins used in this experiment all consist of single polypeptide chains, but differ in their charge and
mass. Bovine serum albumin, with a molecular weight of 68,000 and an isoelectric point (pI) of 4.7, is similar
in structure and function to the serum albumin previously discussed. Ovalbumin is an abundant protein found in
eggs. Ovalbumin, with a molecular weight of 43,000 and pI of 4.6, contains covalently attached carbohydrate and
is therefore a glycoprotein. The polysaccharide chain contains eight (8) sugar residues. The majority of serum proteins are also glycoproteins (except serum albumin). Cytochrome C, a ubiquitous protein with a molecular weight
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Background Information, continued
of 12,000 and pI of 10.7, is involved in electron transport reactions that are mediated by the heme prosthetic group.
Cytochrome C and several other proteins form the electron-transport chain which enables the cell to obtain chemical
energy (ATP) from the oxidation of glucose. In bacteria, cytochrome c is located on the inner surface of the cellular
membrane. Lysozyme, a small protein with a molecular weight of 14,000 and pI of 11.2, is utilized in bacterial cell
lysis. All these proteins are dissolved in a buffer containing glycerol and the negatively charged bromophenol blue
tracking dye. This tracking dye generally migrates faster than the proteins. During the electrophoresis of the serum
proteins, the bromophenol blue may separate into two bands. This separation occurs because some of the serum
proteins bind a fraction of the dye. The bound dye has a slower migration rate than the free dye.
After electrophoresis, the proteins will be visualized by staining with Protein InstaStain® After the gel is destained,
proteins will appear as dark blue zones against a light blue background.
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Experiment Overview
EXPERIMENT OBJECTIVE:
The objective of this experiment module is to develop a general understanding of the structure and electrophoretic
migration of native proteins.
LABORATORY SAFETY
1.
Gloves and goggles should be worn routinely as good laboratory
practice.
2.
Exercise extreme caution when working with equipment which
is used in conjunction with the heating and/or melting of reagents.
3.
DO NOT MOUTH PIPET REAGENTS - USE PIPET PUMPS OR BULBS.
Wear gloves
and safety
goggles
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Preparations for Agarose Gel Electrophoresis
PREPARING THE GEL BED
1.
Make sure the gel bed is clean and dry.
2.
Close off the open ends of the bed by using rubber dams or tape.
A. Using Rubber dams:
•
Place a rubber dam on each end of the bed. Make sure the rubber dam sits firmly in
contact with the sides and bottom of the bed.
B. Taping with labeling or masking tape:
•
•
3.
With 3/4 inch wide tape, extend the tape over the sides and bottom edge of the bed.
Fold extended edges of the tape back onto the sides and bottom. Press contact points firmly to form a
good seal.
Place the well forming template (comb) across the bed in the middle set of notches.
The comb should sit firmly and evenly across the bed.
CASTING THE AGAROSE GEL
This experiment requires a 0.8% gel.
3.
Use a 250 ml flask to prepare the diluted gel buffer.
•
With a 1 ml pipet, measure the buffer concentrate and add the distilled water as indicated in Table A.
4.
Add the required amount of agarose powder. Swirl to disperse clumps.
5.
With a marking pen, indicate the level of the solution volume on the outside of the flask.
Table A
Individual 0.8% UltraSpec-Agarose™ Gel
Size of EDVOTEK
Casting Tray
(cm)
Amt of
Agarose
(g)
7 x 15
0.48
+
Distilled
Total
Concentrated
Buffer (50x) + Water = Volume
(ml)
(ml)
(ml)
1.2
58.8
60
Wear gloves
and safety goggles
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Preparations for Agarose Gel Electrophoresis, continued
6.
Heat the mixture to dissolve the agarose powder. The final solution should be clear (like water) without any
undissolved particles.
A. Microwave method:
• Cover flask with plastic wrap to minimize evaporation.
• Heat the mixture on high for 1 minute.
• Swirl the mixture and heat on high in bursts of 25 seconds until all the agarose is completely dissolved.
B. Hot plate or burner method:
• Cover the flask with foil to prevent excess evaporation.
• Heat the mixture to boiling over a burner with occasional
swirling. Boil until all the agarose is completely dissolved.
7.
Cool the agarose solution to 60°C with careful swirling to promote even dissipation of heat. If
detectable evaporation has occurred, add distilled water to bring the solution up to the original
volume as marked on the flask in step 5.
60˚C
After the gel is cooled to 60°C:
Caution!
If using rubber dams, go to step 9. If using tape, continue with step 8.
8.
Seal the interface of the gel bed and tape to prevent the agarose solution from
leaking.
• Use a transfer pipet to deposit a small amount of cooled agarose to both inside
ends of the bed.
• Wait approximately 1 minute for the agarose to solidify.
9.
Pour the cooled agarose solution into the bed. Make sure the bed is on a level surface.
DO NOT POUR BOILING HOT
AGAROSE INTO THE GEL BED.
Hot agarose solution may
irreversibly warp the bed.
10. Allow the gel to completely solidify. It will become firm and cool to the touch after
approximately 20 minutes.
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Preparations for Agarose Gel Electrophoresis, continued
PREPARING THE SOLIDIFIED GEL FOR ELECTROPHORESIS
11. Carefully remove the rubber dams or tape.
12. Remove the comb by slowly pulling it straight up. Do this carefully and evenly to
prevent tearing the sample wells.
13. Inspect the wells by viewing the gel from the edge nearest the wells. If some of
the wells are ripped through their bottoms or sides, do not use them when loading
samples.
14. Place the gel in the electrophoresis chamber, properly oriented, centered and level on
the platform.
15. Fill the chamber of the electrophoresis apparatus with the required volume of diluted buffer as outlined in
Table B.
16. Load samples in wells; conduct electrophoresis according to experiment instructions. See Table C for time and
voltage guidelines.
Useful Hint!
Step 11: Be careful
not to damage or tear
the gel when removing
rubber dams. A thin
plastic knife or spatula can be
inserted between the gel and the
dams to break possible surface
tension.
Table B
EDVOTEK
Model #
Electrophoresis Buffer
Distilled
Concentrated
Buffer (50x) + Water
(ml)
(ml)
Total
= Volume
(ml)
M6+
6
294
300
M12
8
392
400
M36 (blue)
10
490
500
M36 (clear)
20
980
1000
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Preparations for Agarose Gel Electrophoresis, continued
PRACTICE GEL LOADING
EDVOTEK® experiments which involve electrophoresis contain practice gel loading solution. If your students are
unfamiliar with loading samples in agarose gels, it is suggested that they practice sample delivery techniques
before performing the electrophoresis part of an experiment. Using the EDVOTEK system, sample delivery can be
performed by using either an automatic micropipet, or disposable microtipped transfer
pipets.
Casting of a separate practice gel is highly recommended. One suggested activity for
practice gel loading is outlined below:
1.
Cast a gel with the maximum number of wells and place it under the buffer in an
electrophoresis apparatus chamber. (Use microbiology-grade agar and water to
make practice gels - save the agarose for the experiment.)
2.
Let students practice delivering the practice gel loading solution to the sample
wells.
3.
If students need more practice, remove the practice gel loading solution by squirting buffer into the wells with a transfer pipet.
4.
When students are finished practicing, replace the practice gel with a
fresh gel and continue with the experiment.
The practice gel loading solution will become diluted in the buffer and
will not interfere with the experiment.
Quick Reference:
If you are using an automatic
micropipet, deliver 20 microliters
to the sample well. If using
transfer pipets, load the sample
well until it is full.
Remember!
Use microbiology-grade agar and
water to make practice gels - save
the agarose for the experiment.
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11
EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Conducting Agarose Gel Electrophoresis
This experiment requires a 0.8% UltraSpec-Agarose™ gel. The gel
should be cast with the comb placed in the middle set of notches of the
gel bed. Make sure the electrophoresis apparatus leads reach the power
source before loading samples. The apparatus should not be moved
after the samples are loaded because movement of the unit will cause
samples to spill out of the wells.
LOADING PROTEIN SAMPLES
1.
Consecutively load 40 μl of each sample in tubes A - E
into wells in the middle of the gel.
RUNNING THE GEL
2.
Reminder:
During electrophoresis, the DNA
samples migrate through the
agarose gel towards the positive
electrode. Before loading the
samples, make sure the gel is
properly oriented in the apparatus
chamber.
-
+
Red
Black
Sample wells
Ele
sis
ore
2
ctroph M1
After the samples are loaded, carefully snap the
cover down onto the electrode terminals.
Make sure that the negative and positive indicators on the cover
and apparatus chamber are properly
oriented.
3.
4.
5.
Table C:
Insert the plug of the black wire into
the black input of the power source
(negative input). Insert the plug of
the red wire into the red input of the
power source (positive input).
Volts
Set the power source at the required
voltage and run the electrophoresis
for the length of time as determined
by your instructor. When current is flowing properly, you should see
bubbles forming on the electrodes.
After the electrophoresis is completed, turn off the power, unplug
the power source, disconnect the leads and remove the cover.
Time and
Voltage
Recommended Time
Minimum
Optimal
125
30 min
45 min
70
40 min
1.5 hrs
50
60 min
2.0 hrs
Useful Hint!
After
electrophoresis,
remove a small slice of
the gel from the upper
right hand corner to
easily identify right and left
orientation of the gel after
staining.
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Staining the Gel
ONE-STEP STAINING & DESTAINING WITH PROTEIN INSTASTAIN®
Protein agarose gels can be stained with Protein InstaStain® cards in one easy step – an excellent alternative if
time does not permit staining during a regular class session.
1.
After electrophoresis, submerge the gel and plate in a small tray with 100 ml of fixative solution. (Use enough
solution to cover the gel.)
2.
Gently float a sheet of Protein InstaStain® with the stain side (blue) in the liquid. Cover the gel to prevent
evaporation.
3.
Gently agitate on a rocking platform for 1-3 hours or overnight.
4.
After staining, protein bands will appear as dark blue bands against a light background and will be ready for
photography.
NO DESTAINING IS REQUIRED.
5.
If the gel is too dark, destain in several changes of fresh destain solution until the appearance and contrast of
the protein bands against the background improves.
Fixative and Destaining
Solution for each gel
(100 ml)
50 ml
10 ml
40 ml
Methanol
Glacial Acetic Acid
Distilled Water
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
Study Questions
1.
Under the conditions of the electrophoresis (pH 7.8), which of the proteins (BSA, Ovalbumin, Cytochrome C,
Lysozyme) are net positive? Which are net negative?
2.
Based on your observations, would you expect Ovalbumin to have more or less lysine and arginine residues
than lysozyme? Why?
3.
A sample of native protein is submitted to native gel electrophoresis. After the electrophoresis was run for
several hours, it was found that the protein did not enter the gel from the sample well (did not migrate). What
is the most likely explanation for this observation? What experimental condition could you change that would
allow the protein to migrate?
4.
Consider the following information about the proteins used in this experiment:
Protein
Cytochrome C
Lysozyme
Ovalbumin
BSA
Approximate
Molecular Weight
12,000
14,000
43,000
68,000
Isoelectric
Point (pH)
10.7
11.2
4.6
4.7
All these proteins are spherical in shape, therefore, increasing molecular weight corresponds to increasing size.
The results of the electrophoresis at pH 7.8 should show that Ovalbumin migrates a greater distance towards
the positive electrode than BSA. The results should also show that Lysozyme migrates a greater distance towards the negative electrode than Cytochrome C. Explain the results using the information provided above.
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
INSTRUCTOR'S GUIDE
Instructor's Guide
If you do not find the answers to your questions in this section, a variety of resources are continuously being added
to the EDVOTEK® web site. In addition, Technical Service is available from 9:00 am to 6:00 p.m., Eastern time zone.
Call for help from our knowledgeable technical staff at 1-800-EDVOTEK (1-800-338-6835).
APPROXIMATE TIME REQUIREMENTS FOR PRE-LAB AND EXPERIMENTAL PROCEDURES
1.
Agarose gel preparation: Your schedule will determine when to prepare the agarose gel(s). Whether you
choose to prepare the gel(s), or have the students do it, allow approximately 30 to 40 minutes for this procedure. Generally, 20 minutes of this time is required for gel solidification.
2.
The approximate time for electrophoresis will vary from 45 minutes to 2 hours.
A variety of factors, such as class size, length of laboratory sessions, and availability of equipment, will influence the
implementation of this experiment with your students. These guidelines can be adapted to fit your specific set of
circumstances.
SPECIFIC REQUIREMENTS FOR THIS EXPERIMENT
•
Gel Concentration
This experiment requires a 0.8% UltraSpec-Agarose™ gel.
•
Number of Wells Required
This experiment requires a gel with 5 sample wells.
•
Placement of Comb
During gel casting, the comb should be placed in the notches in the middle of the gel bed.
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15
INSTRUCTOR'S GUIDE
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
EDVO-Kit 111
Prelab Preparations
PREPARING THE ELECTROPHORESIS (CHAMBER) BUFFER
Prepare the appropriate volume of diluted electrophoresis chamber buffer by mixing
the concentrated 50x electrophoresis buffer and distilled or deionized water according
to Table B .
ELECTROPHORESIS TIME AND VOLTAGE
Your schedule will dictate the length of time samples will be separated by electrophoresis. General guidelines are presented in Table C.
Useful Hint!
The same 50x
c o n c e n t r a t e d buffer
is used for preparing
the agarose gel buffer
and the chamber
buffer.
PREPARING STAINING AND DESTAINING SOLUTIONS
Solution for staining with Protein InstaStain®
•
•
Prepare a stock solution of Methanol and Glacial Acetic Acid by combining
180 ml Methanol, 140 ml Distilled water, and 40 ml Glacial Acetic Acid.
No destaining is required.
Wear gloves
and safety goggles
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EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
INSTRUCTOR'S GUIDE
Quick Reference Tables
Table A
Individual 0.8% UltraSpec-Agarose™ Gel
Size of EDVOTEK
Casting Tray
(cm)
Amt of
Agarose
(g)
7 x 15
0.48
Table B
EDVOTEK
Model #
+
Distilled
Total
Concentrated
Buffer (50x) + Water = Volume
(ml)
(ml)
(ml)
1.2
58.8
60
Electrophoresis Buffer
Distilled
Concentrated
Buffer (50x) + Water
(ml)
(ml)
Total
= Volume
(ml)
M6+
6
294
300
M12
8
392
400
M36 (blue)
10
490
500
M36 (clear)
20
980
1000
Time and
Voltage
Electrophoresis of DNA
Table C
Volts
Recommended Time
Maximum
Minimum
125 30 min
45 min
70
40 min
1.5 hrs
50
60 min
2.0 hrs
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INSTRUCTOR'S GUIDE
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
EDVO-Kit 111
Avoiding Common Pitfalls
•
To ensure that protein bands are well resolved, make sure the gel formulation is correct (see Table A on page
17) and that electrophoresis is conducted for the optimum recommended amount of time.
•
Correctly dilute the concentrated buffer for preparation of the gel and electrophoresis buffer. Remember that
without buffer in the gel, there will be no protein mobility. Use only distilled water to prepare buffers. Use
distilled or deionized water.
•
For optimal results, use fresh electrophoresis buffer prepared according to instructions.
•
Before performing the actual experiment, practice sample delivery techniques to avoid diluting the sample with
buffer during gel loading.
•
To avoid loss of protein bands into the buffer, make sure the gel is properly oriented so the samples are not
moving in the wrong direction and off the gel.
•
If protein bands appear faint after staining and destaining, repeat the staining procedure but stain for a longer
period of time.
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18
EDVOTEK, Inc., all rights reserved.
111.051128
EDVO-Kit 111
ELECTROPHORETIC PROPERTIES OF NATIVE PROTEINS
INSTRUCTOR'S GUIDE
Expected Results
(-)
1 2
3 4
5 6
The figure to the left is an idealized schematic showing relative positions of protein polypeptides. The idealized schematic
(left) shows the relative positions of the bands, but are not
depicted to scale. Actual results are shown below.
Lane
Tube
1
2
3
4
5
A
B
C
D
E
Bovine Serum Albumin (BSA)
Ovalbumin
Cytochrome C
Lysozyme
Horse Serum Proteins
(-)
1 2
3 4
5 6
(+)
(+)
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19
Please refer to the kit
insert for the Answers to
Study Questions