Peyton's Environmental Biotechnology Group

Current Students and Post-Doctoral Fellows (Spring 2012)

Under construction Feb 2012

Tisza Bell

Ph.D. Student (Microbiology)


Robert Gardner

Ph.D. Student (CHBE-MSU)

Increased necessity to limit dependence on foreign fossil fuels along with elevated concerns involving increasing carbon dioxide levels have intensified the search for carbon neutral renewable fuels.  Biodiesel consisting of methyl esters of fatty acids, produced from microalgae, has the economic potential to replace petroleum based fuel utilized within the current national infrastructure.  Our research is focusing on isolation, and optimization, of algal strains which produce elevated levels of Triacylglyerol, composed of fatty acids chains esterified to glycerol, that can be extracted and transesterified with alcohol to produce biodiesel.  Photo - Rob receiving the CBE's 2012 Characklis award from Nancy Characklis.


Lisa Kirk

PhD. Student (LRES-MSU)

Lisa is a doctoral candidate in MSU’s Land Resources and Environmental Sciences department.  She is a Fellow of the Inland Northwest Research Alliance, the Montana Water Center, and the US EPA Science to Achieve Results (STAR) program.  Her research in the Peyton Lab is focused on understanding subsurface ecology conditions that influence microbial reduction of selenium in backfilled phosphate mine waste, with a goal of developing operational strategies for insitu source control based on waste management practices.  Her interdisciplinary research involves the fields of microbiology, geochemistry, soil physics, and mineralogy, and relies heavily on analytical chemistry and molecular biology methods.  Lisa plans to integrate her doctoral training in microbial ecology with her professional practice of environmental geochemistry, as a means of improving options for protection of water resources through operational management of mine waste.


Lisa Kirk in laboratory

Natasha Mallette

Ph.D. Student (CHBE)


Karen Moll

M.S. Student (Microbiology)


Hannah Newhouse

Undergraduate Student (CHBE)


Elle Pancratz

Undergraduate Student (CHBE)


Heidi Schoen

M.S. Student (CHBE)


Rich Macur

Research Faculty


Dana Skorupa

Post-Doctoral Fellow


Brandy Stewart

Post-Doctoral Fellow

Brandy’s post-doctoral project is focused on elucidating the dominant mechanisms of U(IV) oxidation by Fe(III) (hydr)oxides, common constituent of soils and sediments. Historic uranium mining and enrichment activities have created a legacy of radioactive wastes and co-contaminants. Due to radioactivity and chemical toxicity uranium is a threat to human health and the environment. Reduction of uranium from U(VI) to U(IV) generally results in a decrease in aqueous uranium concentration, thus limiting the mobility of uranium in the environment. This process is often facilitated by microbes, suggesting the potential for in situ bioreductive immobilization as a remediation strategy. Despite the promise of reductive immobilization, biologically reduced uranium is susceptible to reoxidation by a variety of common oxidants including nitrate, Fe(III), and oxygen. This work will contribute to our overall understanding of uranium biogeochemical cycling in the environment and improve our understanding of reoxidation mechanisms, an integral component of uranium’s potential for migration in the subsurface. 

Ari Staven

M.S. Student (CHBE-MSU)

Ari was also an undergraduate researcher. Her undergraduate research activities are described below.

Lisa Weeks

M.S. Student (CHBE-MSU)



Former Students


Research Group Snapshot Fall 2008

Everett Eustance

M.S. Student (CHBE)

Ari Staven

Undergrad (ChBE-MSU)

Ari joined the Lake Coeur d’Alene Project in the Fall of 2007 and began working on the second phase of the project to quantify the role of individual members of the microbial community in biogeochemical cycling of metals. Ari ran batch experiments to quantify the effects of pH on zinc toxicity to Arthrobacter sp. isolated from the lake. This summer Ari worked on a project for a large corporation, developing a biofilm-based protocol using a CDC reactor and analyzing the results from the coupon sampling. Ari is currently working on an Undergraduate Scholar Program (USP) funded project, Zinc Toxicity to Single and Mixed Species Biofilms: An Analysis with Contemporary Molecular Techniques and is fervently pursuing her degree in Chemical Engineering with an expected graduation date in May 2010.

Catherine VanEngelen

Ph.D. Student (CHBE-MSU)

Catherine is studying the chemical and biological degradation of explosives. Specific focus for this research is on the nitrogen-containing explosive compounds TNT (2,4,6-trinitrotoluene), TNB (1,3,5-trinitrobenzene), and nitrocellulose. While it is known that explosives are transformed (often to hazardous products) under highly alkaline (pH > 14) conditions, it has been observed that different transformations occur at more moderate alkalinity (7 < pH > 14). Using elevated temperatures to increase the rate of this chemical reaction, the addition of a biological entity may further degrade the products of alkaline hydrolysis to non-hazardous end products. The microorganism currently being used as a biological component was isolated from an alkaline hot spring in YNP and has been identified as Anoxybacillus kualawohkensis. With the aim of combining the abiotic effect of alkaline hydrolysis with thermoalkaline microorganisms from Yellowstone National Park (YNP), it is anticipated that a more complete and environmentally-friendly method for explosives remediation will be developed.

Mike VanEngelen

Ph.D. Student (CHBE-MSU)

The accumulation of uranium in oilfield sea-water injection pipelines represents both a human health and environmental liability. It is believed that the accumulation of uranium is a result of the reduction of soluble U(VI) species to insoluble U(IV) species, a process carried out by the metabolic activity of sulfate reducing bacteria (SRB). Mike is currently investigating methods of accumulation prevention, principally through U(IV) re-oxidation mechanisms. Recent experiments using CSTR bioreactors demonstrated the potentially positive role of nitrate on the U(IV) re-oxidation processes. The results of these preliminary experiments showed that the use of appropriate chemical additives could provide methods of successful mobilization of uranium species in oilfield sea-water injection pipelines. Further investigations include the construction of a CSTR-in-series bioreactor system, one aimed at better simulating flow through a pipeline. In addition, a variety of chemical additives, including nitrate, nitrite, and iron, and chemical additive combinations will be screened for their U(IV) re-oxidizing capability.

James Moberly

Ph.D. Student (CHBE-MSU)

James is currently a member of a research team investigating microbial contributions to toxic heavy metal cycling in the Coeur d'Alene area, focusing on lead, copper, and zinc. He has isolated metal tolerant aerobic organisms, identified them by using 16sRNA analysis, and is currently working on doing the same for iron and sulfate reducing organisms. Kinetic and heavy metal interaction studies of these organisms are planned in the near future. He has been operating a novel flow reactor for four months (as of December 2005) which simulates the contaminated sediments of the Coeur d'Alene area and in which we can monitor microbial and geochemical changes. In the future, a consortium of the isolated metal tolerant organisms will be placed into the flow reactor on a defined substrate of quartz and ferrihydrate and microbial and geochemical changes will be monitored both temporally and spatially. This information will be incorporated into a biogeochemical model to better predict this complex system.

Seth D'Imperio

Post-Doctoral Fellow

Seth’s post-doctoral research is focused on the use of a 16S-based microarray (PhyloChip) that was developed at Berkeley National Laboratory for the description of complex microbial communities. The microarray format allows for rapid and comprehensive taxonomic classification of microbial consortia as more than 8,500 Bacterial and Archaeal operational taxonomic units can be detected simultaneously from a single sample without the need for cloning and sequencing. He is currently applying the PhyloChip technology in order to better understand the impact of heavy metal (Zn, Hg, U, etc) contamination on microbial communities in Lake Coeur d’Alene, ID, the Idrijca River in Slovenia and a waste site at the Idaho National Laboratory.



Crystal Giradot

M.S. Student (CHBE-MSU)

Crystal Girardot is a master's student working with Desulfovibrio vulgaris Hildenborough which is a gram-negative, anaerobic bacteria isolated from the soil.  D. vulgaris potentially produces siderophores and Crystal is working to isolate these siderophores and identify them.  Siderophores are iron chelating compounds produced by the bacteria to help in the intake of iron.  A better understanding of these siderophores could help with bioremediation techniques.


Jared Bozeman

Undergrad (CBN-MSU)

Jared Bozeman is an undergraduate in Cell Biology and Neuroscience.  He assists Lisa Kirk in her Study of selenium-reducing bacteria in Southeast Idaho.

John Aston

Ph.D. Student (CHBE-MSU)

John studies the acidothermophilic bacterium: Acidithiobacillus caldus to better characterize the toxicity and assimilation of organic acids and the toxicity and sorption of lead, zinc, and copper to this microorganism. Acidithiobacillus caldus is believed to play an important role in sulfur cycling and metal mobilization in acid-mine environments. The goal of John’s work is to improve the understanding of this microorganism in acid-mine environments. An increased understanding of this and similar microbes may lead to improved design of acidic metal-leaching systems. John’s work is supported by an Integrated Graduate Education Research Training Fellowship as well as the NSF Montana Experimental Program to Stimulate Competitive Research program.


Sutapa Barua

M.S. Student (CHBE-MSU)

Sutapa is working on Lake Coeur d'Alene (LCDA) sediment with Dr. Peyton, Dr. Sani and James. We are trying to figure out what microorganisms are present in LCDA sediment and how they play an important role in biogeochemical cycling of Pb, Zn and Cu (these metals are in significant amount in our sample). The mechanism of how bacteria can remove these metals is largely unknown. The 16s-rDNA analysis, that have been done so far, show the presence of different bacterial genera e.g. Sphingobacteria, Cyanobacteria, Actinobacteria, Gammaproteobacteria, Clostridia etc in LCDA sediment.

Sarah Mullowney

Undergrad. Student (CHBE-MSU)


Sarah is new to the lab and is currently assisting Catherine with experiments on halophilic biodegradation of aromatic compounds and beginning to look at screening techniques for selected thermophilic enzymes.

Abbie Richards

Ph.D. Student (CHBE-MSU)

To date, few studies have investigated the production of siderophores (extracellular, organic molecules that bind ferric iron) by microorganisms capable of growing in saline and alkaline environments. Soap Lake, located in Washington State, is the subject of an NSF funded Microbial Observatory and is a naturally occurring saline and alkaline lake that contains siderophore producing microorganisms. Nine isolates from Soap Lake were found to be siderophore producers. Bacteria that thrive under saline and alkaline conditions are capable of producing siderophores. For her work, Abbie has won numerous awards at national and international conferences.

Abbie Richards at poster session

Joe Sibbert

Undergrad. Student (CHBE-MSU)

Joe is new to the lab and is currently assisting Abbie with her halophilic siderophore projects by preparing media, pouring agar plates, and running assays for siderophore activity and concentrations.


Joe Sibbert in laboratory