Call: (240) 314-6294
Call: (240) 314-6294
- Helen Hay Whitney Foundation Post-Doctoral Fellow, Memorial Sloan-Kettering Cancer Center, 1997-2000
- Helen Hay Whitney Foundation Post-Doctoral Fellow, Johns Hopkins School of Medicine, 1995-1996
- Ph.D., Molecular Biology, Cornell University Graduate School of Medical Sciences, New York, 1995
- MSc., Cell Biology, Weizmann Institute of Science, Rehovot, Israel, 1989
- BSc., Agriculture, Hebrew University of Jerusalem, Rehovot, Israel, 1987
Dr. Zvi Kelman’s research is focused on developing tools and reagents for the labeling of biomolecules with stable isotopes to support biophysical and bioanalytical measurements. The NIST Biomolecular Labeling Laboratory also provides support to external users through a proposal process. The Kelman laboratory has the equipment and reagents necessary for production, purification, and characterization of labeled proteins and other biomolecules, including peptides and nucleic acids.
The lab also studies the mechanism of DNA replication in archaea and other organisms. Through biochemical, structural, and genetic approaches, the lab studies the initiation and elongation phases of DNA replication using the thermophilic archaeon Thermococcus kodakarensis as a model organism.
Expression and purification of monoclonal antibodies
Monoclonal antibodies (mAbs) are commonly developed by the pharmaceutical industry as drugs to fight a large variety of diseases, including cancer and autoimmune disease. Some structural studies on mAbs will benefit from the ability to label the antibodies with stable isotopes, including 2H, 13C, and 15N. The lab is developing tools for Escherichia coli expression and purification of full-length labeled mAbs, as well as Fc and Fab antibody fragments.
Labeled protein expression in yeast
Overexpression of recombinant proteins in yeast enables studies of eukaryotic proteins that require post-translational modifications by pathways that are not present in E. coli. However, in yeast, overexpression of recombinant proteins is reduced several-fold in 2H-enriched media. The lab is using the yeast Pichia pastoris as a model organism to improve protein production in the presence of 2H2O. Using a combination of mutagenesis and genetic manipulation, the team is engineering P. pastoris cells that can produce high levels of labeled protein in high (>85%) 2H2O growth conditions.
Studies on the archaeal primase
During the study of T. kodakarensis primase, the Kelman lab discovered a unique enzymatic activity. In the presence of dATP and small molecules (SM) with an OH group, the enzyme will make an AMP-SM adduct. The lab is using structure-based mutagenesis to modify the enzyme and enable it to form adducts between larger molecules and additional nucleotides, including deoxy- and ribonucleotides.