Jocelyne DiRuggiero Associate Research Professor Department of Biology Ph.D. University Claude Bernard, Lyon, France M.Sc. University Claude Bernard, Lyon, France B.Sc. 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. The approach is to study microorganisms that live in extreme environments, such as deep-sea hydrothermal vents and hypersaline lakes, 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 research presently addresses two fundamental questions:

1- What is the extent of genetic diversity in natural microbial populations and what generates and maintains that diversity?
We use environmental genomics and molecular tools to characterize the microbial diversity of natural populations from extreme environments.

2- What are the mechanisms for the repair of DNA lesions in Archaea?
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.

REPRESENTATIVE PUBLICATIONS

White J.R., Escobar-Paramo P., Mongodin E.F., Nelson K.A. and J. DiRuggiero.
Extensive Genome Rearrangements and Multiple Horizontal Gene Transfers in a Population of Pyrococcus Isolates from Vulcano Island, Italy. Appl. Environ.
Microbial. In press.

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., González 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 1:277–283.

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 Web Site

Lab Members

Visiting Student:
Courtney Robinson