The Sullivan Lab
PEOPLE
Bill Sullivan, Ph.D.: PRINCIPAL INVESTIGATOR
Dr. Sullivan obtained his Ph.D. in Cell & Molecular Biology from the University of Pennsylvania in 1997. His graduate work, performed in the lab of Dr. David Roos, focused on using novel genetics tools to probe mechanisms of drug resistance in Toxoplasma. After a postdoc at Eli Lilly & Co, he became an Assistant Research Professor under the mentorship of Dr. Sherry Queener at the Indiana University School of Medicine (IUSM) to examine gene regulation in Toxoplasma. He is now a Showalter Professor at IUSM in the Department of Microbiology & Immunology. Dr. Sullivan served on the AOIC study section at NIH from 2016-2019. Dr. Sullivan is an editor/writer at PLOS SciComm, served on the Editorial Board of mSphere, and chairs the Editorial Advisory Board of ASBMB Today. He is the co-chair of the CTSI Concept-to-Clinic Project Development Team.
Dr. Sullivan is also the author of the book, Pleased to Meet Me: Genes, Germs, and the Curious Forces That Make Us Who We Are (National Geographic). He has been featured in a wide variety of outlets, including CNN, Fox & Friends, The Doctors, Science Fantastic with Dr. Michio Kaku, Doctor Radio, and more. He has published over 100 papers in scientific journals and has written for The Washington Post, WIRED, Discover, Scientific American, COSMOS, Psychology Today, The Conversation, and more.
Email. X/Twitter. LinkedIN. Bluesky. Faculty homepage.
Michael Holmes, Ph.D.: ASSISTANT RESEARCH PROFESSOR
Dr. Michael Holmes obtained his Ph.D. in Biochemistry from the University of Windsor in 2015. His graduate work, performed in the laboratory of Dr. Sirinart Ananvoranich, focused on the study of developmentally regulated transcript-specific translational repression in Toxoplasma gondii bradyzoites. Mike joined the Sullivan lab in July, 2015 and is working on understanding how changes in translational control relate to the tachyzoite - bradyzoite interconversion process. He was promoted to Assistant Research Professor in 2022.
Matheus Bastos, Ph.D.: POSTDOCTORAL FELLOW
Dr. Bastos obtained his Ph.D. in Agricultural Biochemistry (focused on biochemistry and molecular biology) from the Federal University of Viçosa in 2014. His graduate work, performed in the lab of Dr. Juliana Fietto, studied the role of NTPDases in purinergic signaling and virulence in the protozoan parasite Leishmania. He then completed postdoctoral studies on a project entitled anti-parasitic drug discovery in epigenetics (2014-2016, Juliana Fietto Lab). From 2016-2019, he worked in the laboratory of Dr. Luiz R.O. Tosi (University of São Paulo) investigating DNA repair mechanisms in Leishmania. Matheus joined the Sullivan Lab in August 2020 to study the role of mRNA modifications and translation control in Toxoplasma gondii.
Vanessa Severo, Ph.D.: POSTDOCTORAL FELLOW
Dr. Severo obtained her Ph.D. in Biosciences and Biotechnology from the Carlos Chagas Institute - FIOCRUZ/PR, Brazil, in 2022. Her graduate work was performed in the laboratory of Dr. Sheila Nardelli, focused on the characterization of histone H1 from Toxoplasma gondii. Vanessa joined the Sullivan Lab in March 2023 to study translation initiation factors driving persistence of Toxoplasma gondii bradyzoites in neurons."
Talon Gilchrist: Ph.D. GRADUATE STUDENT
Talon earned his B.S. in Microbiology at the University of Michigan in 2022. As an undergraduate, he studied lung fibrosis and viral immunology in Dr. Beth Moore's lab. Following graduation, Talon worked to understand flavivirus infection and replication in Dr. Andrew Tai's lab at U-M. Talon began his PhD at IU School of Medicine in August 2024 and joined the Sullivan Lab in May 2025. He is interested in studying the mechanisms of translational control in relation to Toxoplasma tachyzoite-bradyzoite conversion.
Abigail Hall: Ph.D. GRADUATE STUDENT
Abigail earned her B.A. in Biology from Earlham college in 2015. Post-graduation, she worked as a contract research associate at Corteva working on the discovery of novel insecticidal proteins. In 2019, she joined IU as a staff member working in the lab of Dr. Nathan Alves at IUSM studying novel drug delivery strategies for thrombolytics and the effects of microplastic exposure on coagulation. Abigail joined the IUSM (as a graduate student this time) in 2024 and the Sullivan lab in 2025. The focus of her doctoral research is studying cap-dependent and cap-independent mechanisms of translational control in Toxoplasma.
Lab alumni
POSTDOCTORAL FELLOWS/ASSISTANT RESEARCH PROFESSORS
Vishakha Dey (Postdoctoral fellow 3/2020-2/2025)
Sandeep Srivastava (Postdoctoral fellow 3/2017-6/2022)
Leo Augusto (Postdoctoral fellow 7/2016-10/2020)
Victoria Jeffers, Ph.D. (Postdoctoral fellow 11/2010-12/2015; Assistant Research Professor 1/2016-12/2018)
Michael Harris, Ph.D. (Postdoctoral fellow 3/2015-7/2018)
Min Zhang, Ph.D. (Assistant Research Professor, 1/2017-3/2018)
Imaan Benmerzouga, Ph.D. (Postdoctoral fellow 1/2014-7/2015)
Anne Bouchut, Ph.D.(Postdoctoral fellow 3/2013-10/2014)
Tingkai Kevin Liu, Ph.D. (Postdoctoral fellow 3/2011-9/2013)
Christian Konrad, Ph.D. (Postdoctoral fellow 8/2009-7/2013)
Bradley Joyce, Ph.D. (Postdoctoral fellow 8/2007-4/2013)
Vanina Elias, Ph.D. (Postdoctoral fellow 2/2009-8/2010)
Arunasalam Naguleswaran (Nagul), Ph.D. (Postdoctoral fellow 4/2006-8/2010)
Nathalie Vonlaufen, Ph.D. (Postdoctoral fellow 3/2007-2/2008)
Jana Narasimhan, Ph.D. (Postdoctoral fellow 8/2004-7/2006)
GRADUATE STUDENTS
Edwin Flores (MS/MS Spring 2023)
Jennifer Martynowicz (MD/PhD 6/2016 - 12/2019)
Jocelyne Hanquier (MS 6/2017 - 11/2019)
Joe Varberg (PhD 6/2013 - 6/2017)
Leah Padgett (PhD 6/2013 - 6/2017)
Sherri Huang (MD/PhD 6/2013 - 12/2016)
Krista Stilger (PhD 6/2009 - 10/2013)
Jiachen Wang (MS 6/2010 - 5/2013)
David O. Onyango (PhD 6/2007-1/2011)
Stacy E. Dixon (MD/PhD 6/2006-6/2010)
Micah M. Bhatti (MD/PhD 6/2002-5/2005)
Karuna Nallani Tirumala (MS 8/2002-7/2004)
Aaron T. Smith (MS 9/2003-9/2005)
Apryl Underwood (MS/MS Spring 2005)
Christina Bennett (MS/MS Spring 2005)
Kelli Bramlett (MS 9/2003-7/2006)
RESEARCH TECHNICIANS
Sarah Abney (Research Technician 3/2008-12/2011)
Aaron T. Smith, MS (Research Technician 9/2005-2/2008)
Meredith Livingston, MS (Research Analyst 4/2004-8/2007)
VISITING STUDENTS AND POSTDOCS
Anna Saldarriaga (Dr. Sergio Angel, 2021)
Diego Ruiz, PhD (Dr. Sergio Angel, 2019)
Valeria Turowski, PhD (Dr. Sergio Angel, 2019)
Thomas Gimeno (STEM student, summer 2018)
Nic Wheeler (undergraduate honors student, summer 2012)
Silvina Bogado (Dr. Sergio Angel, summer 2011 and 2013)
Krista Podell (summer undergrad MURF student, Univ Indianapolis, 2010)
Kaitlin Flynn (summer undergrad, Earlham, 2009)
Carolina Dalmasso (Dr. Sergio Angel, summer 2007, 2008)
WORK-STUDY STUDENTS
Tiffany Novak (2017-2018)
Gian Gballou (2016)
Eunice Jeong (2012)
Ariel Auerbach (2011)
Candice Childs (2011)
Nis Jose (2010)
Kristin Geros (2010)
Dillon Etter (Summer 2009)
Angie Pierle (Spring 2009)
Wendy Cowles (Spring/Summer/Fall 2008)