Associate Professor, Departments of Pathology, Molecular and Human Genetics, and Molecular Virology & Microbiology; Programs in Cell and Molecular Biology and Translational Biology and Molecular Medicine
Co-Director, M.D./Ph.D. Medical Scientist Training Program

B.A., University of Texas, Austin, TX, 1985
Ph.D./M.D., Baylor College of Medicine, Houston, TX, 1995
Postdoc in Digestive Diseases, Baylor College of Medicine, Houston, TX, 1996
Resident in Clinical Pathology, Massachussets General Hospital, 1998
Clinical Fellow in Pathology, Harvard Medical School, Boston, MA, 1999
Postdoc in Comparative Medicine, M.I.T., Cambridge, MA, 1999

Versalovic Lab

RESEARCH INTERESTS:

Probiotics and Therapeutic Microbiology

The Versalovic Laboratory is studying the functional genomics of probiotic (beneficial) bacteria for therapeutic purposes. Probiotic bacteria derived from commensal organisms are being studied as natural modulators of the immune system (anti-inflammatory features), beneficial microbes to improve digestion, and antagonists to bacterial pathogens (anti-infective features). Genetic manipulation of beneficial bacteria will be applied to engineer probiotics for the control of mucosal inflammation and prevention of infections. The human microbiome is also under investigation in the context of pediatric gastrointestinal diseases.

Animal models (rodents and piglets) are being combined with human biology to explore the molecular mechanisms of probiosis. Lactobacillus reuteri is being investigated as a model probiotic bacterium. Current collaborations with the Human Genome Sequencing Center at Baylor include genome sequencing of multiple Lactobacillus genomes for the human microbiome project. Comparative genomics will be applied to the understanding of biological pathways and networks in probiotic bacteria. Custom microarrays have been created to investigate gene expression profiles of probiotic bacteria under different conditions in the laboratory. Projects include studies of bacterial gene expression and proteomics so that bacterial cellular systems can be understood at a fundamental level. Secreted factors including carbohydrates and polypeptides are being studied as components of the bacterial secretome. A detailed understanding of the secretome and how molecules are secreted will enable bacterial engineering to deliver new treatments in the gastrointestinal tract and oral cavity.

Systems biology approaches comprise an integral part of the lab's strategies for understanding beneficial interactions between commensal bacteria and the innate immune system. Candidate probiotic genes identified by microarrays and bioassays may uncover signaling and transport pathways in bacteria that participate in bacterial:host interactions. Mammalian cell culture models in the laboratory are being utilized to study bacterial:host interactions. Specifically, intestinal epithelial cells and macrophages are being studied by microarrays, RNAi, and signaling assays so that mammalian cellular responses to beneficial bacteria can be explored in detail.

SELECTED PUBLICATIONS:

1. Therapeutic Microbiology: Probiotics and Related Strategies (2008). Versalovic J and Wilson M (eds.). American Society for Microbiology Press, Washington D.C.

2. Lin YP, Thibodeaux CH, Peña JA, Ferry GD, Versalovic J (2008). Probiotic Lactobacillus reuteri suppress proinflammatory cytokines via c-Jun. Inflamm. Bowel Dis. 14: 1068-1083.

3. Iyer C, Kosters A, Sethi G, Kunnumakkara AB, Aggarwal BB, Versalovic J (2008). Probiotic Lactobacillus reuteri promotes TNF-induced apoptosis in human myeloid leukemia-derived cells by modulation of NF-kB and MAPK signalling. Cell Microbiol. 10: 1442-1452.

4. Spinler JK, Taweechotipatr M, Rognerud CL, Ou CN, Tumwasorn S, Versalovic J (2008). Human-derived probiotic Lactobacillus reuteri demonstrate antimicrobial activities targeting diverse enteric bacterial pathogens. Anaerobe 14: 166-171.

5. Zhang WW, Versalovic J (2007). Expanding the diagnostic capabilities of molecular microbiology by genomic methods. J. Mol. Diagn. 9: 572-573.

6. Alyamani EJ, Brandt P, Peña JA, Major AM, Fox JG, Suerbaum S, Versalovic J (2007). Helicobacter hepaticus catalase shares surface-predicted epitopes with mammalian catalases. Microbiology 153: 1006-1016.

7. Versalovic J, Relman D (2006). How bacterial communities expand functional repertoires. PLoS Biol. 4: 2193-2195.

8. Guarner F, Bourdet-Sicard R, Brandtzaeg P, Gill HS, McGuirk P, van Eden W, Versalovic J, Weinstock JV, Rook GAW (2006). Mechanisms of disease: the hygiene hypothesis revisited. Nat. Clin. Pract. Gastroenterol. & Hepatol. 3: 275-284.

For more publications, see listing on Pub Med.

CONTACT INFORMATION:

James Versalovic, M.D., Ph.D.
Department of Pathology
Texas Children's Hospital
6621 Fannin St. MC 1-2261
Houston, Texas 77030

Phone: 832-824-2213
Fax: 832-825-0164
E-mail:

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