Principal Investigator

Bess Ward - Diversity of functional groups in microbial nitrogen cycle, denitrification and nitrification, nitrogen cycling in marine, estuarine and Antarctic Lake environments, microbial (bacteria and phytoplankton) processes in biogeochemistry.

Graduate Students

Anita Adhitya - Genetic diverstiy and regulation of nitrate reductase genes in marine microbes.

Sarah Fawcett - The effect of increasing concentrations of atmospheric CO₂ on biogeochemical processes in the ocean. Additionally I am interested in the interface of climate change science and mitigation policy in the developing world, particularly in Southern Africa.



Silvia Newell - investigation of functional diversity in denitrification using nirS microarrays for diversity and gene expression.

Post Doctoral Research Scientists

Punyasloke Bhadury - Investigating phytoplankton functional diversity using molecular approaches, molecular ecology, biotechnology.




Nik Bouskill - The use of quantitative and semi-quantitative methods to investigate the spatial and temporal diversity and abundance of ammonia oxidizing bacteria and archaea.




Jeremy Rich - Anaerobic ammonium oxidation (anammox) and denitrification in aquatic and terrestrial systems; molecular and ecological aspects of bacterial biogeochemistry.

Research Scientists

Amal Jayakumar - Diversity of nitrite reductase genes oxygen depleted waters of the Arabian Sea; Estimating rates of nitrogen transformations in the oxygen minimum zone of Eastern Tropical North Pacific using a Matlab model; Microbial transformations of trace gases (methane, nitrous oxide).

Gone But Not Forgotten

Andy Allen - Applying molecular, chemical tracer, and stable isotope techniques to investigate aquatic biogeochemical element cycles and to examine relationships among distribution, abundance and activity of organisms, genes, and enzymes and the overall rate and magnitude of key geochemical transformations (e.g., nitrogen cycling); Molecular characterization of nitrate reductase (NR) genes in heterotrophic bacteria and diatoms, molecular approaches to phytoplankton community structure and activity, and bacteria-phytoplankton interactions with limiting nutrients.

Jenny Baeseman - Diversity and community dynamics of denitrifying bacteria in the seasonal streams of the McMurdo Dry Valleys, Antarctica.




Karen Casciotti - Genetic diversity of genes involved in nitrous oxide production in nitrifying and denitrifying bacteria; isotope fractionation association with nitrogen transformations (1998 - 2002). (Currently National Reseach Council Fellowship post doc at USGS, Reston VA).



Evan Chyun





Chris Francis - Molecular, biochemical, and ecological aspects of the microbial cycling of nitrogen and metals in the environment; Determining the key organisms and molecular mechanisms underlying microbial processes through laboratory and field studies.



Joshua Nelson - Diversity patterns in marine bacteria over time and space; Functional gene diversity investigated using gene microarrays.

Gregory D. O'Mullan - Biocomplexity of microbial nitrogen cycling; Diversity-function relationships in marine microbial systems; Molecular diversity of marine nitrifying bacteria; Population genetics of marine communities (e.g. Bathymodiolus mussels, whale shark); Hybrid alterations; Hydrothermal vent ecology.


Danielle Schmitt




Bongkeun Song - Biogeochemical cycle of nitrogen, Anaerobic biodegradation, Anaerobic respiration and metabolic pathways, Diversity of functional genes in marine phytoplankton and denitrifying bacteria.

Gaspar Taroncher-Oldenburg -HABs (Harmful Algal Blooms); Saxitoxin biosynthesis in dinoflagellates and cyanobacteria (Alexandrium fundyense, Aphanizomenon); biodegradable polymer production in cyanobacteria (polyhydroxyalkanoate synthase genes in Synechocystis); metabolic engineering of cyanobacteria; expression profiling in Synechocystis and Synechococcus using genome microarrays; functional diversity of microbial processes in the marine environment.

Caroline Tuit - Microbial biogeochemistry, particularly the role of trace metals in the mediation of the nitrogen cycle. The roles of microorganisms in mediating trace metal speciation, rates of transport and catalytic processes in water and sediments in both pristine and polluted environments.

Princeton University
Department of Geosciences