R. Stephen Lloyd, Ph.D.

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DNA repair processes and high fidelity DNA replication represent the major mechanisms to maintain genomic stability. Our laboratory uses multi-disciplinary approaches to focus on:

  • Strategies to prevent sunlight-induced skin cancer via the topical introduction of repair enzymes into human cells;
  • The mechanisms by which the loss of a DNA repair enzyme can lead to the clinical manifestations of Metabolic Syndrome - a constellation of diseases (obesity, fatty liver disease, insulin resistance and hypertension) that affect >45 million Americans;
  • The molecular mechanisms by which environmental toxicants create mutations in DNA; and
  • The cellular response mechanisms for the repair of DNA-protein crosslinks.

  • Summary of Current Research

    Dr. R. Stephen Lloyd received his BS in Biology from Florida State University in 1975, majoring in marine pollution biology. His research interests turned to cancer chemotherapy and in 1979, he earned his Ph.D. in Molecular Biology from the University of Texas Graduate School of Biomedical Sciences in Houston, TX. After learning about mechanisms by which DNA can be damaged, he began his career in DNA repair as a postdoctoral fellow at Stanford University in the laboratory of Dr. Philip Hanawalt. Following two years at Stanford, he worked for two more years for a genetic engineering company, before joining the Biochemistry Department at Vanderbilt University in 1983. In his ten-year stay at Vanderbilt, Dr. Lloyd rose through the ranks to Full Professor, and his research focused on both DNA repair and molecular mutagenesis. He was then recruited to the Center for Molecular Science at the University of Texas Medical Branch in which the faculty exclusively specialized in DNA repair mechanisms. During his twelve years at UTMB, he also became the Director of two Centers in Environmental Toxicology. In August 2003, he, along with his wife, Dr. Amanda K. McCullough was recruited to join the CROET faculty at OHSU. Together they have both separate and joint research projects in the research areas described below.

    Selected Publications

    "Error-prone replication bypass of the primary aflatoxin B1 DNA adduct, AFB1-N7-Gua," Journal of Biological Chemistry (Vol: 289, Issue: 26, Page 18497-18506) - 2014

    "Molecular basis of aflatoxin-induced mutagenesis-role of the aflatoxin B1-formamidopyrimidine adduct," Carcinogenesis (Vol: 35, Issue: 7, Page 1461-1468) - 2014

    "Pyrosequencing: Applicability for studying DNA damage-induced mutagenesis," Environmental and Molecular Mutagenesis (Vol: 55, Issue: 8, Page 601-608) - 2014

    "Inhibition of DNA glycosylases via small molecule purine analogs," PLoS ONE (Vol: 8, Issue: 12, ) - 2013

    "Inhibition of HIV-1 Reverse Transcriptase-Catalyzed Synthesis by Intercalated DNA Benzo[a]Pyrene 7,8-Dihydrodiol-9,10-Epoxide Adducts," PLoS ONE (Vol: 8, Issue: 9, ) - 2013



      Email R. Stephen Lloyd

    503 494-8638