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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 have inhabited the Earth for 3.4 billion years of its history. They are essential for the evolution of its minerals, its major geochemical cycles, and its atmosphere, yet the extent of their diversity, their metabolic capabilities, and their ecosystem-level interactions remains vastly unexplored.

Understanding the link between the geochemistry we observe and the large-scale impact of microbial activity is critical if we want to learn more about our own biosphere, and how to better conserve and protect the environment. We study microorganisms that live in extreme environments, such as hypersaline environments and extremely dry deserts, because under those extreme conditions - where the impact on cellular components is intense - microorganisms have evolved robust adaptive mechanisms.

Our work focuses on processes that allow microorganisms to adapt to their environments and to changing environmental conditions. We are particularly interested in mechanisms of resistance to oxidative stress, desiccation, and radiation. We use a combination of genomic and genetic methods to identify proteins involved in the repair of DNA damage in the Archaea and to elucidate the regulatory networks underlying the stress response to cellular damage.

At the ecosystem level, we study the genetic and functional diversity of microbial communities from extreme environments to identify the mechanisms that sustain biodiversity and ecosystem functioning. Our field sites include the Atacama Desert, Chile, and the Dry Valleys of Antarctica, both extremely dry areas and Earth analogs for Martian environments.

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


Atacama Desert, Chile

Atacama desert image 1 Atacama desert image 2

Representative Publications

Wierzchos, J., J. DiRuggiero, P. Vìtek, O. Artieda, V. Souza-Egipsy, P. Skaloud, M. Tisza, A. F. Davila, C. Vìlchez, I. Garbayo, and C. Ascaso. Adaptation strategies of endolithic chlorophototrophs to survive the hyperarid and extreme solar radiation environment of the Atacama Desert. In press.

Davila, A.F., I. Hawes, J. Garcia, D.R. Gelsinger. J. DiRuggiero, C. Ascaso, A. Osano, and J. Wierzchos. In situ metabolism in halite endolithic microbial communities of the hyperarid Atacama Desert. In press.

Robinson, C. K., J. Wierzchos, C. Black, A. Crits-Christoph, B. Ma, J. Ravel, C. Ascaso, O. Artieda, S. Valea, M. Roldan, B. Gomez-Silva, and J. DiRuggiero. 2015. Microbial diversity and the presence of algae in halite endolithic communities are correlated to atmospheric moisture in the hyper-arid zone of the Atacama Desert. Environ Microbiol doi: 17: 299-315

Crits-Christoph, A., C. K. Robinson, T. Barnum, J. Ravel, F. Fricke, A. Davila, B. Jedynak, C.P. McKay, and J. DiRuggiero. 2013. Colonization patterns of soil microbial communities in the Atacama Desert. Microbiome 1:28.

DiRuggiero, J., J. Wierzchos, C. K. Robinson, T. Souterre, R. Ravel, O. Artieda, V. Soua- Egipsy, and C. Ascaso. 2013. Microbial colonization of chasmoendolithic habitats in the hyper-arid zone of the Atacama Desert. Biogeosciences 10:2439-2450

Webb, K., J. Wu, C.K. Robinson, N. Tomiya, Y. Lee, and J. DiRuggiero. 2013. Effects of intracellular Mn on the radiation resistance of the halophilic archaeon Halobacterium salinarum. Extremophiles. 17: 485-497

Webb, K.M., and J. DiRuggiero. 2012. Role of Mn2+ and compatible solutes in the radiation resistance of thermophilic bacteria and archaea. Archaea. 2012:Article ID 845756. doi:10.1155/2012/845756

Robinson, C.K., K.M. Webb, A. Kaur, P. Jaruga, M. Dizdaroglu, N. Baliga, A. Place, and J. DiRuggiero. 2011. A major role for non-enzymatic antioxidant processes in the radioresistance of Halobacterium salinarum. J. Bacteriol. 193:1653-1662

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

Postdoctoral Fellows:

Victoria Meslier

Graduate Students:

Diego Gelsinger
Kevin Maciuba

Research Technologist:

Jeremiah Miller

Undergraduate students:

Alex Crists-Christoph
Philip Lin