1. 4rd Lecture
Advanced Aminal Cell Culture
2013 2nd Semester
Department of Animal Science
Chungbuk National University

2. Syllabus
Date
Topics
September 5, 2013
Introduction : What is Cell Culture?
September 12, 2013
Cell Culture As Model System For Research
September 26, 2013
Cell Culture For Antibody / Protein Production
October 17, 2013
Protein Production/Purification
October 31, 2013
Stem Cell I
November 14, 2013
Stem Cell II
November 28, 2013
TG/KO Animals
December 5, 2013
Genome Engineering/NGS
December 12, 2013
Final Exam

3. Date
September 26, 2013
Cell Culture For
Antibody / Protein
Production
조유미, Madhusumida
October 17, 2013
Protein
Production/Purification
이미진, 정용호
이영, 윤준호
October 31, 2013
November 14, 2013
Stem Cell I
Jia Jia Lin, 염동현
November 28, 2013
Stem Cell II
Zhao MingHui,권정우
December 5, 2013
Transgenic Animals
Lin Zili, 이상배
December 12, 2013
Genome
Engineering/NGS
조유진, 김상욱

4. Protein Purification
• Recombinant protein expressed in mammalian cells : 20,000 extra proteins
• Desired protein should be purified from other proteins
• Based on characteristics of proteins
(Size, Surface charge, Affinity…)
• Unlike DNA/RNA, Every protein behave differently..
- Purification method should be developed by every single protein.

5. Protein Purification Principles
- Ion-exchnage
Different protein has different ionic properites (Positive or Negative)
- Gel Filtration
Seperation based on Protein Size
- Affinity
Some protein bind specific ligands
- UltraFiltration
Concentration of Protein / Desalting

6. Ion-exchange chromatography
- Purification based on protein surface charge

7. - Anion Exchange Chromatography
Resin has (+) charge on it
Negative (anion) charged protein bound on the resin
By increase of anion (Cl-) concetration, protein eluted from the resin
Q-Sepharose : Strong Anion Exchanger
DEAE-Sephasrose : Moderately strong anion exchanger

8. - Cation Exchange Chromatography
Resin has (-) charge on it
Positive (cation charged protein bound on the resin
By increase of cation(For example, Na+) concentration, protein eluted from the resin
S-Sepharose : Strong cation Exchanger
CM-Sepharose : Moderately strong cation exchanger

9. Examples of Ion-exchange
chromatography resin
Mono-Q and Mono-S : Strong anion (Q) and cation (S) exchanger

10. General Procedure of Ion Exchange Chromatography
1. Load Sample
Unbound protein goes to flow through column
2. Wash Sample with low salt buffer
3. Increase Salt Concentration by Gradients
Lower Salt : Weak binding
Higher Salt : Strong binding

11. Pros
It can bind very large amount of sample : Ideal for initial capturing of desired protein
Good for the sample concentration
If it is optimized, it can increase purification yield significantly
General Purpose chromatography (You can use it most of soluble proteins)
Cons
Sample should be stable at low salt (less than 100mM) buffer
Procedure should be optimized (case by case)

12. Affinity Chromatography
- Use resin which can bind specifically desired protein
- Examples :
Protein A sepharose : bind to IgG
GSH sepharose : Glutathione transferase
Ni-NTA Sepharose : PolyHistidine
Chitin bead : Cellulose binding protein
- Before genetic manipulation, Affinity chromatography
was very limited usages.
- But now it is one of major techniques for protein
purifications

13. Affinity tag addition using recombinant
RNA technology
- Most of protein does not have specific affinity bead to bind.
- We can add specific tag on protein to facilliate purification
Target Protein Gene
Affinity tag Gene
Affinity
Tag
Affinity Bead
Affinity
Tag
Target Protein Gene
Target Protein Gene

14. PolyHistidine Tag (His-tag) : Can bind to Ni-NTA bead
Blue Color From Nickel
Glutathione S-transferase Tag (GST-tag) : Can bind to Glutathione Sepharose
FLAGTM tag (DYKDDDDK) : Can bind Flag-tag recognize antibody

16. • Pros
- Very high level of purification can be achieved
- Initial Capturing
•
-
Cons
Limited Affinity Resin
At least modification of protein is required
Cleavage of Tag

17. Size Exclusion Chromatography
- Separate protein based on sizes
- Small protein enter bead, while big protein
migrate fast
- Mainly used for the final step of purification
(Protein Polishing)

19. • Pros
- Can separate protein based on the oligomeric
state
- Final Polishing of protein
•
-
Cons
Seperation depend on the loading volumes
Sample should be highly concentrated
Limitation of protein amount

20. Multistep purification
Affinity chromatography
(Initial capturing)
Ion exchange chromatography
(Intermediate purification)
Size Exclusionchromatography
(Polishing Step)

21. Measurement of Purity
SDS-PAGE
Endotoxin detection
-Endotoxin : Generally refer ‘bacterial originated lipoplysaccharide’ (LPS)
- Induces unwanted immune response
- Should be removed for the biologic productions