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Jocelyne DiRuggiero

Associate Research Professor

235B Levi Hall
Department of Biology
Johns Hopkins University
3400 N. Charles Street
Baltimore, MD 21218-2685
Office 410 516-8498
Lab 410 516-7744
Departmental fax 410 516-5213
Lab webpage


University Claude Bernard, Lyon, France


University Claude Bernard, Lyon, France


University Claude Bernard, Lyon, France

Research Interests

Microorganisms are responsible for key steps in biogeochemical cycles on Earth, yet the extent of their diversity and metabolic capabilities remains vastly underestimated. By increasing our knowledge of their genetic diversity, evolution and ecology we will learn more about our biosphere and how to better conserve resources and protect the environment.

Our research focuses on the processes that allow microorganisms to adapt to their environment and to changing environmental conditions. We study microorganisms that live in extreme environments, such as deep-sea hydrothermal vents, hypersaline environments, and extremely dry dserts where insults to the cellular components are intense; organisms that inhabit these ecosystems have evolved robust adaptive mechanisms.

We are particularly interested in the microbial diversity of microorganisms in extreme environments, in the evolutionary mechanisms that drive genome alteration in response to environmental changes, and in the molecular mechanisms of DNA repair and stress response.

Our main research projects are:

Molecular responses of extremophilic Archaea to environmental changes

  • Oxidative stress, desiccation, and radiation

DNA repairs systems in the Archaea

  • Homologous recombination, MutS2

Microbial genomics of extreme environments

  • Microbial communities structure and composition in the Atacama Desert and the Dry Valleys of Antarctica
  • Genetic diversity and genome evolution

Our research is directly related to Astrobioloy. Visit the Astrobiology web site at JHU at



Representative Publications

Kaur, A., P.T. Van, C.R. Busch, C. Robinson, M. Pan, W.L. Pang, D. Reiss, J. DiRuggiero, and N.S. Baliga. 2010. Coordination of frontline defense mechanisms under severe oxidative stress. In press Mol. Syst. Biol.

Busch, C.R., and J. DiRuggiero. MutS and MutL are dispensable for maintenance of the genomic mutation rate in the halophilic archaeon Halobacterium salinarum NRC-1. 2010. PLoS ONE, doi:10.1371/ journal.pone.0009045.

Kish, A., G. Kirkali, C. Robinson, R. Rosenblatt, P. Jaruga, M. Dizdaroglu, and J. DiRuggiero. 2009. Salt Shield: Intracellular Salts Provide Protection against Ionizing Radiation in the Halophilic Archaeon, Halobacterium salinarum NRC-1 Environ. Microbiol. 11:1066-1078

White J.R., Escobar-Paramo P., Mongodin E.F., Nelson K.A. and J. DiRuggiero. 2008. Extensive Genome Rearrangements and Multiple Horizontal Gene Transfers in a Population of Pyrococcus Isolates from Vulcano Island, Italy. Appl Environ Microbiol. 74:6447-6451 Recommended by Faculty of 1000 Biology:

Kish, A., and J. DiRuggiero. 2008. Rad50 is Not Essential for the Mre11-Dependant Repair of DNA Double Strand Breaks in Halobacterium sp. str. NRC-1. J. Bacteriol. 190:5210-5216.

Bonneau R., Facciotti M.T., Reiss D.J., Schmid A.K., Pan M., Kaur A., Thorsson V., Shannon P., Johnson M.H., Bare J.C., Longabaugh W., Vuthoori M., Whitehead K., Madar A., Suzuki L., Mori T., Chang D.E., DiRuggiero J., Johnson C.H., Hood L., Baliga N.S. 2007. A predictive model for transcriptional control of physiology in a free living cell. Cell. 131:1354-65.

Whitehead* K., A. Kish* A., M. Pan, A. Kaur, D.J. Reiss, N. King, L. Hohmann, J. DiRuggiero and N. S. Baliga. 2006. Stress management: Using a systems approach to understand stress response to gamma radiation
(*these authors contributed equally to this work).

Mol. Syst. Biol. 2:47 Williams E., T. Lowe, J. Savas and J. DiRuggiero. 2006. Microarray analysis of the Pyrococcus furiosus exposed to gamma irradiation. Extremophiles 1:19-29.

Escobar-Paramo P., S. Gosh and J. DiRuggiero. 2005. Evidence for genetic drift in the diversification of a geographically isolated population of the hyperthermophilic archaeon Pyrococcus. Mol. Biol. Evol. 22:2297 2303.

Kottemann M., A. Kish, S. Bjork, C. Iloanusi and J. DiRuggiero. 2005. Desiccation and gamma irradiation repair in the halophilic archaeon Halobacterium NRC1. Extremophiles 9: 219-227.

Kanoksilapatham W., Gonzlez J.M., Maeder D.L., DiRuggiero J. and F.T. Robb. 2004. A proposal to rename the hyperthermophile Pyrococcus woesei as Pyrococcus furiosus, sub sp. woesei. Archaea 1:277283.

Baliga N., S. Bjork, R. Bonneau, M. Pan, C. Iloanusi, M. Kottermann, H. Hood. and J. DiRuggiero. 2004. Systems level insights into mechanisms of stress response to UV irradiation in Halobacterium sp. NRC-1. Genome Res. 14:1025-1035

Lab Members

Graduate Students:

Jerry Yu

Research Technologist:

Jeremiah Miller

Undergraduate students:

Dominique Seow
Shabeg Singh