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> Chemical and Biological Engineering
> B. Peyton > Research Brent M. Peyton

Peyton's Environmental Biotechnology Group
Current Students and Post-Doctoral Fellows (Fall 2008)


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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. |
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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.
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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.
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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. |
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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.
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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.
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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.
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J. Storm
Shirley
PhD.
Student (Microbiology-MSU)
Storm is working with
alkalithermophiles (organisms thriving at pH >8.5, and temp. >60°C)
collected from the Witch Creek area of Heart Lake in Yellowstone
National Park. His goal is to analyze community structure, and to
identify and characterize novel organisms that may yield commercial
promise.
Applications for industrial processes
are long term goals from this phase of research. It is believed that
many of these high pH and temperature organisms will be identified and
enriched from samples originating at this site. His research will focus
primarily on anaerobic organisms; but will also include aerobic cultures
as needed. Storm’s background is molecular biology in Eukaryotic
systems (specifically, cardiac metabolism) and he has only recently
changed his research focus to the world of microbes and environmental
biology after over 16 years working with animal models.
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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. |
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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. |
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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. |
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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.
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Former
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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.
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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. |
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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.
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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.
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