JCVI: About / Bios / Keehwan Kwon
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Keehwan Kwon, Ph.D.
Assistant Professor

Research Interests and Accomplishments

Dr. Keehwan Kwon joined The Institute for Genomic Research (TIGR) as a Staff Scientist in 2004.  As a group leader in the Pathogen Functional Genomics Resource Center, he has directed the design and development of high throughput recombinant protein expression platforms, including construction of specialized expression vectors, implementation of automation and purification methods, and protein functional assays using fluorescence- and protein microarray-based strategies. Thus, a protein production pipeline was established that has resulted in the expression of more than 3000 genes derived from a variety of pathogenic bacteria, e.g. Streptococcus pneumonia, Bacillus anthracis, Yersinia pestis, Staphylococcus aureus and Francisella tularensis.

One of Dr. Kwon's major research interests is to use the combination of expressed proteins and assay platforms to determine the function of many uncharacterized and hypothetical proteins. In this context, Dr. Kwon's team has established assays to screen for protease and transcription factor activities as well as a variety of ligand-binding functions (DNA, carbohydrates, protein-protein interactions part of multi-subunit complexes). Another main interest area is to characterize the response of the human immune system to bacterial infection, using a protein microarray-based platform. His team also clones and expresses target genes from more than 20 microbial species, an effort related to the NIAID's Center for Structural Genomics of Infectious Disease. Candidate proteins are determined for scale-up protein purification followed by X-ray crystallography.

Dr. Keehwan Kwon received his undergraduate education in Genetic Engineering at Korea University in Seoul, Korea, in 1991. Dr. Kwon received his Ph.D. degree in Biochemistry in 2000 studying in the laboratory of Dr. Beckett at the University of Maryland where he biochemically and biophysically characterized the role of a flexible loop of E. coli biotin ligase (BirA) in allosterism for gene regulation and enzymatic functions. Dr. Kwon continued his research as a Post-Doctoral Fellow in the laboratory of Dr. Stivers at Center for Advanced Research in Biotechnology (CARB) and at the School of Medicine, Johns Hopkins University, where he studied kinetic aspects of the activities of vaccinia virus topoisomerase I and DNA repair enzymes (uracil DNA glycosylase and 3-methyladenine DNA glycosylase I) and also developed a high throughput method for screening vaccinia virus topoisomerase I inhibitors.


Assays for Identification of Topoisomerase Inhibitors, WO2006/015369 (Pending).

Fluorescence Assay for Type IB DNA Topoisomerase, PCT/US2005/027605 (Pending).

Select Publications

Kwon, K., Pieper, R., et al.
A Correlation Analysis of Protein Characteristics Associated With Genome-wide High Throughput Expression and Solubility of Streptococcus pneumoniae Proteins

Protein Expr Purif. 2007 Oct 01; 55(2): 368-78.[more]

Nagarajan, R., Kwon, K., et al.
Catalytic Phosphoryl Interactions of Topoisomerase IB

Biochemistry. 2005 Aug 30; 44(34): 11476-85.[more]

Kwon, K., Nagarajan, R., et al.
Ribonuclease Activity of Vaccinia DNA Topoisomerase IB: Kinetic and High-throughput Inhibition Studies Using a Robust Continuous Fluorescence Assay

Biochemistry. 2004 Nov 30; 43(47): 14994-5004.[more]

Cao, C., Kwon, K., et al.
Solution Structure and Base Perturbation Studies Reveal a Novel Mode of Alkylated Base Recognition by 3-methyladenine DNA Glycosylase I

J Biol Chem. 2003 Nov 28; 278(48): 48012-20.[more]

Kwon, K., Cao, C., et al.
A Novel Zinc Snap Motif Conveys Structural Stability to 3-methyladenine DNA Glycosylase I

J Biol Chem. 2003 May 23; 278(21): 19442-6.[more]

Kwon, K., Jiang, Y. L., et al.
Rational Engineering of a DNA Glycosylase Specific for an Unnatural Cytosine:pyrene Base Pair

Chem Biol. 2003 Apr 01; 10(4): 351-9.[more]

Drohat, A. C., Kwon, K., et al.
3-Methyladenine DNA Glycosylase I Is an Unexpected Helix-hairpin-helix Superfamily Member

Nat Struct Biol. 2002 Sep 01; 9(9): 659-64.[more]

Kwon, K., Streaker, E. D., et al.
Binding Specificity and the Ligand Dissociation Process In the E. coli Biotin Holoenzyme Synthetase

Protein Sci. 2002 Mar 01; 11(3): 558-70.[more]

Kwon, K., Jiang, Y. L., et al.
19F NMR Studies of Vaccinia Type IB Topoisomerase. Conformational Dynamics of the Bound DNA Substrate

J Biol Chem. 2002 Jan 04; 277(1): 353-8.[more]

Kwon, K., Stivers, J. T.
Fluorescence Spectroscopy Studies of Vaccinia Type IB DNA Topoisomerase. Closing of the Enzyme Clamp Is Faster Than DNA Cleavage

J Biol Chem. 2002 Jan 04; 277(1): 345-52.[more]

Weaver, L. H., Kwon, K., et al.
Competing Protein:protein Interactions Are Proposed to Control the Biological Switch of the E coli Biotin Repressor

Protein Sci. 2001 Dec 01; 10(12): 2618-22.[more]

Jiang, Y. L., Kwon, K., et al.
Turning On Uracil-DNA Glycosylase Using a Pyrene Nucleotide Switch

J Biol Chem. 2001 Nov 09; 276(45): 42347-54.[more]

Weaver, L. H., Kwon, K., et al.
Corepressor-induced Organization and Assembly of the Biotin Repressor: a Model for Allosteric Activation of a Transcriptional Regulator

Proc Natl Acad Sci U S A. 2001 May 22; 98(11): 6045-50.[more]

Kwon, K., Streaker, E. D., et al.
Multiple Disordered Loops Function In Corepressor-induced Dimerization of the Biotin Repressor

J Mol Biol. 2000 Dec 15; 304(5): 821-33.[more]

Kwon, K., Beckett, D.
Function of a Conserved Sequence Motif In Biotin Holoenzyme Synthetases

Protein Sci. 2000 Aug 01; 9(8): 1530-9.[more]