Chae Un Kim

Chae Un Kim, Ph.D.

192 Clark Hall, Cornell University
Ithaca, NY 14853-2501

Tel: (607) 255-8678
Fax: (607) 255-8751

Email: ck243@cornell.edu

Careers

Korean Army

1101 Engineer Corps, Kwang-Ju Gun, Kyung-Gi Do, Korea, 1999 ~ 2001.

Education

B. S.

Seoul National University, Seoul, Korea, 1995 ~ 1999 (Physics).

Ph. D.

Cornell University, Ithaca, NY 14853, USA, Sep. 2002 ~ Jan. 2008 (Biophysics), High Pressure Cryocooling for Macromolecular Crystallography. Gruner Lab - Biophysics.

Post Doctoral Research Associate

Cornell University, Ithaca, NY 14853, USA, Aug 2007 ~ Current, Gruner Lab - Biophysics.

Research Area: High Pressure Cryocooling for Macromolecular Crystallography

Protein crystallography is an essential technique in biomedical sciences. Use of this technique typically requires cryocooling crystals to reduce radiation damage in data collection stage. So far protein crystals have most commonly been frozen by flash cryocooling at ambient pressure, which often requires a time-consuming searching for cryoprotection conditions. Recently, we have developed an alternative procedure, high pressure cryocooling, which usually does not require penetrative cryoprotectants. The result of high pressure cryocooling is very often dramatic in terms of diffraction resolution and mosaicity as seen in the left figure. We are currently investigating the underling basic principles and important experimental parameters for the optimization of high pressure cooling method.

In parallel, since this method involves the use of helium gas as a pressurizing medium, we have focused on the extension of our method to diffraction phasing by incorporating heavy noble gases, such as krypton or xenon. In the test case of Porcine Pancreas Elastase (PPE, 240 residues (26kDa)), very high quality diffraction was obtained by the Kr-He high pressure cyrocooling method without the help of cryoprotectants. Furthermore, a single 0.31 occupied krypton site in a PPE molecule (Bijvoet amplitude ratio (<|ΔF|>/<F>) of 0.53 %) could be successfully used for SAD phasing at 1.3 Å resolution (see figure right). We are currently working on the machine modification for the procedure optimization, which should be compatible with the high throughput crystallography pipeline.

Publications

6. Buz Barstow, Nozomi Ando, Chae Un Kim and Sol M. Gruner, Alteration of Citrine Structure by Hydrostatic Pressure Explains the Accompanying Spectral Shift, Proc. Natl. Acad. Sci., In Press.

5. Chae Un Kim, Yi-Fan Chen, Mark W. Tate and Sol M. Gruner (2008), Pressure Induced High-density Amorphous Ice in Protein Crystals, J. Appl. Cryst. 41, 1-7 (pdf).

4. Chae Un Kim, Quan Hao and Sol M. Gruner (2007), High Pressure Cryocooling for Capillary Sample Cryoprotection and Diffraction Phasing at Long Wavelengths, Acta Cryst. D63, 653-659 (pdf).

3. Ronald A. Albright, Jose-Luis Vazquez Ibar, Chae Un Kim, Sol M. Gruner and Joao Henrique Morais-Cabral (2006), The RCK domain of the KtrAB K+ transporter: multiple conformations of an octameric ring, Cell 126, 1147-1159 (pdf, supplementary, CHESS-news).

2. Chae Un Kim, Quan Hao and Sol M. Gruner (2006), Solution of Protein Crystallographic Structures by High Pressure Cryocooling and Noble Gas Phasing, Acta Cryst. D62, 687-694 (pdf).

1. Chae Un Kim, Raphael Kapfer and Sol M. Gruner (2005), High Pressure Cooling of Protein Crystals without Cryoprotectants, Acta Cryst. D61, 881-890 (pdf, CHESS-news).

Awards

4. 2007-2008 CHESS Thesis Prize

High Pressure Cryocooling for Macromolecular Crystallography, CHESS Users Meeting, June 10-11, 2008, Cornell University

3. Oxford Cryosystems poster prize

Chae Un Kim and Sol M. Gruner, High Pressure Cooling of Protein Crystals without Cryoprotectants, 2005 American Crystallographic Association (ACA), May 28 ~ June 2, Orlando, FL, USA

2. Cornell Fellowship (Field of Biophysics), 2002 ~ 2003, Cornell University

1. B.S. graduation with Summa Cum Laude (atop Physics department), 1999, Seoul National University.

Meetings & Conferences

16. (Award talk, invited) Chae Un Kim, High Pressure Cryocooling for Macromolecular Crystallography, 2008 CHESS Users Meeting, June 10-11, 2008, Cornell University, Ithaca, NY, USA

15. (Talk, invited) Chae Un Kim, Quan Hao and Sol M. Gruner, High pressure cryocooling for Capillary Sample Cryoprotection and Diffraction Phasing at Long Wavelengths, American Crystallographic Association (ACA), July 21 ~ 26, 2007, Salt Lake City, Utah, USA

14. (Talk, invited/ Poster presentation) Chae Un Kim, Quan Hao and Sol M. Gruner, High pressure cryocooling for Capillary Sample Cryoprotection and Diffraction Phasing at Long Wavelengths, 2007 CHESS Users Meeting, June 12 ~ 13, Cornell University, Ithaca, NY, USA

13. (Talk, promoted/ Poster presentation) Yi-Fan Chen, Chae Un Kim, Quan Hao and Sol M. Gruner, Automated High Pressure Cryoprotection and Noble Gas Phasing for High-throughput Protein Structure Determination, 6^th Protein Structure Initiative (PSI) “Bottlenecks” Workshop, March 19 ~ 21, 2007, Bethesda, MD, USA

12. (Poster presentation) Chae Un Kim, Quan Hao and Sol M. Gruner, High pressure cryocooling for Capillary Sample Cryoprotection and Diffraction Phasing at Long Wavelengths, 51^st Biophysical Society Meeting, Mar 3 ~ 7, 2007, Baltimore, MD, USA

11. (Talk, invited) Chae Un Kim & Sol M. Gruner, Status of High Pressure Crystal Cryocooling Studies, 2006 Center for High Throughput Structural Biology Annual Meeting, Aug 13 ~ 15, Buffalo, NY 14203

10. (Poster presentation) Chae Un Kim, Quan Hao and Sol M. Gruner, Solution of Protein Crystallographic Structures by High Pressure Cryocooling and Noble Gas Phasing, 2006 American Crystallographic Association (ACA), July 22 ~ 27, Honolulu, Hawaii, USA

9. (Poster presentation) Chae Un Kim, Quan Hao and Sol M. Gruner, Solution of Protein Crystallographic Structures by High Pressure Cryocooling and Noble Gas Phasing, 2006 CHESS Users Meeting, June 13, Cornell University, Ithaca, NY, USA

8. (Poster presentation) Chae Un Kim, Quan Hao and Sol M. Gruner, Solution of Protein Crystallographic Structures by High Pressure Cryocooling and Noble Gas Phasing, ERL X-ray Science Workshops, June 5 ~ 24, 2006, Cornell University, Ithaca, NY, USA

7. (Talk, contributed) Chae Un Kim and Sol M. Gruner, High Pressure Cooling of Protein Crystals without Cryoprotectants, 9^th International Conference on Synchrotron Radiation Instrumentation (SRI), May 28 ~ June 2, 2006, Daegu, Korea

6. (Poster presentation) Chae Un Kim, Quan Hao and Sol M. Gruner, Solution of Protein Crystallographic Structures by High Pressure Cryocooling and Noble Gas Phasing, 5^th Protein Structure Initiative (PSI) “Bottlenecks” Workshop, April 13 ~14, 2006, Bethesda, MD, USA

5. (Poster presentation) Chae Un Kim and Sol M. Gruner, High Pressure Cooling of Protein Crystals without Cryoprotectants,5^th Protein Structure Initiative (PSI) “Bottlenecks” Workshop, April 13 ~14, 2006, Bethesda, MD, USA

4. (Talk, invited/ Poster presentation) Chae Un Kim and Sol M. Gruner, High Pressure Cooling of Protein Crystals without Cryoprotectants, 20^th Congress of the International Union of Crystallography, Aug 23 ~ 31, 2005, Florence, Italy.

3. (Talk, invited/ Poster presentation) Chae Un Kim and Sol M. Gruner, High Pressure Cooling of Protein Crystals without Cryoprotectants, 2005 CHESS Users Meeting, June 14 ~15, Cornell University, Ithaca, NY, USA.

2. (Poster presentation) Chae Un Kim and Sol M. Gruner, High Pressure Cooling of Protein Crystals without Cryoprotectants, 2005 American Crystallographic Association (ACA), May 28 ~ June 2, Orlando, FL, USA.

1. (Poster presentation) Chae Un Kim, Raphael Kapfer and Sol M. Gruner, High Pressure Freezing of Protein Crystals without Cryoprotectants, 2005 Biophysical Society Meeting, Feb 12 ~16, Long Beach, LA, USA.

Upcoming Meetings and Conferences to attend

1. Fifth International High Pressure Bioscience and Biotechnology Conference, Sept 15-19, 2008, San Diego, CA, USA.