Research

RESEARCH INTERESTS

• DNA damage and repair

• Biochemistry

• Enzymology

• Toxicology

RESEARCH SUMMARY

Undergraduate research

As an undergraduate at Miami University (OH), I conducted research for Dr. Ann Hagerman in the Department of Chemistry and Biochemistry. This work involved characterizing free radical formation and stability of tannins and plant polyphenols in varying aqueous solutions. I also studied oxidative stress in rats due to exercise by monitoring biomarkers urea, Vitamin C and Vitamin E in crude rat blood plasma. The primary techniques that I used were electron paramagnetic resonance (EPR), high pressure liquid chromatography (HPLC), and photospectrometry.

I also participated in the Research Experiences for Undergraduates (REU) program at Bowling Green State University (OH) under the supervision of Dr. Scott Rogers in the Department of Biological Sciences. During this summer program, I worked in a team that helped identified microbes isolated in 10,000 to 400,000 year old glacial samples from Greenland and Antarctica. The primary techniques used in our research were polymerase chain reaction (PCR), DNA sequencing using big dye technology, and sequence analysis.

Graduate research

I conducted graduate research at The Ohio State University under the supervision of Dr. Zucai Suo in the Department of Chemistry and Biochemistry. In particular, I studied the pre-steady kinetic and biochemical characteristics of DNA damage bypass (also known as translesion DNA synthesis or TLS) when catalyzed by the X- and Y-family DNA polymerases in the presence of specific DNA lesions. The primary techniques that I learned were enzyme kinetics using the Kintek rapid chemical quench apparatus, circular dichroism (CD) spectroscopy, fluorometry, isothermal titration calorimetry (ITC), DNA analysis via gel electrophoresis methods, molecular cloning, fast purification liquid chromatography (FPLC), protein purification from E. coli, and protein engineering.

Postdoctoral research

At Duke University (NC) under the mentorship of Dr. Paul Modrich in the Department of Biochemistry, I studied the biochemical outcomes of DNA mismatch repair (MMR) in the presence of specific exogenous factors. I also studied the role of endonuclease MutLα in the prevention of cadmium-induced inhibition of MMR. The primary techniques that I learned were in vitro reconstitution of the MMR system, protein purification from SF9 insect cells, nuclear extraction from HEK 293T and HeLa cells, preparation of DNA substrates using cesium bromide banding method, subcloning using bacmid material, and DNA purification via HPLC.

RESEARCH PUBLICATIONS

Current works cited in Google Scholar and PubMed

  1. Sherrer, S.M., Penland, E., and Modrich, P. (2018) The mutagen and carcinogen cadmium is a high-affinity inhibitor of the zinc-dependent MutLα endonuclease. PNAS 115, 7314 – 7319.

  2. Taggart, D.J., Camerlengo, T.L., Harrison, J.K., Sherrer, S.M., Kshetry, A.K., Taylor, J.S., Huang, K., and Suo, Z. (2013) A High-Throughput and Quantitative Method to Assess the Mutagenic Potential of Translesion DNA Synthesis. Nucleic Acids Res 41, e96.

  3. Sherrer, S.M., Taggart, D.J., Pack, L.R., Malik, C.K., Basu, A.K., and Suo, Z. (2012) Quantitative analysis of the mutagenic potential of 1-aminopyrene-DNA adduct bypass catalyzed by Y-family DNA polymerases. Mutat Res 737, 25 – 33.

  4. Sherrer, S.M., Maxwell, B.A., Pack, L.R., Fiala, K.A., Fowler, J.D., Zhang, J., and Suo, Z. (2012) Identification of an Unfolding Intermediate for a DNA Lesion Bypass Polymerase. Chem Res Tox 25, 1531 – 40.

  5. Sherrer, S.M., Sanman, L.E., Xia, C.X., Bolin, E.R., Malik, C.K., Efthimiopoulos, G., Basu, A.K., and Suo, Z. (2012) Kinetic Analysis of the Bypass of a Bulky Lesion Catalyzed by Human Y-family DNA Polymerases. Chem Res Tox 25, 730 – 40.

  6. Song, Q., Sherrer, S.M., Suo, Z., and Taylor, J.S. (2012) Preparation of a site-specific T=mCG cis-syn cyclobutane dimer-containing template and its error-free bypass by yeast and human polymerase eta. J Biol Chem 287, 8021 – 8.

  7. Sherrer, S.M., Fiala, K.A., Fowler, J.D., Newmister, S.A., Pryor, J., and Suo, Z. (2011) Quantitative Analysis of the Efficiency and Mutagenic Spectra of Abasic Lesion Bypass Catalyzed by Human Y-Family DNA Polymerases. Nucleic Acids Res 39, 609 – 622.

  8. Sherrer, S.M., Beyer, D.C., Xia, C.X., Fowler, J.D., and Suo, Z. (2010) Kinetic basis of sugar selection by a Y-family DNA polymerase from Sulfolobus solfataricus P2. Biochemistry 49, 10179 – 10186.

  9. Brown, J.A., Pack, L.R., Sherrer, S.M., Kshetry, A., Newmister, S.A., Fowler, J.D., Taylor, J.S., and Suo, Z. (2010) Identification of Critical Residues for the Tight Binding of Both Correct and Incorrect Nucleotides to Human DNA Polymerase λ. J Mol Biol 403, 505 – 515.

  10. Brown, J.A., Zhang, L., Sherrer, S.M., Taylor, J.S.A., Burgers, P.M.J., and Suo, Z. (2010) Pre-Steady State Kinetic Analysis of Truncated and Full-Length Saccharomyces cerevisiae DNA Polymerase Eta. J Nucleic Acids, pii: 871939. doi:10.4061/2010/871939.

  11. Brown, J.A., Fiala, K.A., Fowler, J.D., Sherrer, S.M., Newmister, S.A., Duym, W.W., and Suo, Z. (2010) A Novel Mechanism of Sugar Selection Utilized by a Human X-family DNA Polymerase. J Mol Biol 395, 282 – 290.

  12. Sherrer, S.M., Brown, J.A., Pack, L.R., Jasti, V.P., Fowler, J.D., Basu, A.K., and Suo, Z. (2009) Mechanistic Studies of the Bypass of a Bulky Single-Base Lesion Catalyzed by a Y-Family DNA Polymerase. J Biol Chem 284, 6379 – 6388.

  13. Fiala, K.A., Sherrer, S.M., Brown, J.A., and Suo, Z. (2008) Mechanistic Consequences of Temperature on DNA Polymerization Catalyzed by a Y-family DNA Polymerase. Nucleic Acids Res 36, 1990 – 2001.