Peter Christensen (Dr. Brant Kedrowski)
The synthesis of chiral molecules, or those that exist in either left-handed
or right-handed forms, is a complicated and challenging area of organic
chemistry research. This complexity presents both an interesting and
exciting challenge when building molecules. The current synthesis of
chiral molecule cacalol results in a racemic mixture, or mixture of two
different mirror image molecules, as the final product. It is for this reason
that the continued focus on this molecule should be directed toward the
resolution of the left-handed and right-handed forms of the molecule.
Attempts on this front have included crystal separation via diastereomer
formation with various chiral auxiliaries, as well as attempting asymmetric
synthesis by forming and utilizing chiral Lewis acid catalysis.
Results From Several Wisconsin Water Bodies
Adam Dach (Dr. Kevin Crawford)
Anatoxin-a and beta-methylamino-L-alanine (BMAA) are both neurotoxins
found in certain cyanobacteria. Anatoxin-a was reported as the cause of
death of a high school boy after swimming in a golf course pond in Dane
County, WI. Pet and livestock deaths from algae-contaminated drinking
waters have also been reported since 1878. Recent studies have shown a
link between both Alzheimer’s and Parkinson’s patients and the presence
of BMAA in the brain. A recent study of toxins in Wisconsin lake waters
detected anatoxin-a in three of 14 samples containing toxins. Though
BMAA has been found in certain cyanobacterial strains in laboratory
cultures, no data exists on the presence of the compound in Wisconsin
water bodies. We have developed a method for measuring both anatoxin-a
and free BMAA simultaneously using liquid chromatography with
fluorescence detection. Both anatoxin-a and BMAA are reacted with
4-fluoro-7-nitrobenzofurazan (NBD-F) to make them fluorescent before
separation by HPLC. We will report on the performance measures of our
method and the results of analysis of 10 lake water samples collected in
August 2008.
(Vaccinium macrocarpon) Powder
Patrick Fischer, Jeffrey Curless
(Drs. Teri Shors and Brant Kedrowski)
This research examines the antiviral properties of cranberry powder. Both
chemical and biological methods are integral to the project. Cranberry 90MX
powder will be used in this study. Separation will begin with a series of
extractions of the cranberry products with solvents of increasing polarity.
Chromatographic methods including solid phase extraction (SPE) and HPLC
will further separate these extracts into pure compounds. Biological assays
will guide the isolation at each step toward active compounds. The bioassays
test for antiviral activity against vaccinia virus grown in BS-C-1 cells.
BS-C-1 cells are grown in EMEM5 supplemented with antibiotics and fetal
bovine serum. All cells and viral infections are maintained in a 37 ºC, 5% CO2
environment. Confluent monolayers of BS-C-1 cells will be infected with ~100
Plaque Forming Units (PFUs) of vaccinia virus containing no cranberry or
cranberry extract during a one hour adsorption step at room temperature.
Subsequently, the cranberry/viral mixture is aspirated and the cells overlaid
with EMEM2.5. The viral infections will proceed 48 hours before plaques
are visualized by staining with 0.1% crystal violet. Once isolated, the structures
of the bioactive compounds will be elucidated using chemical instrumentation.
Andrew Loken (Dr. Jennifer Mihalick)
Flavonoids are an interesting group of molecules. They often give plants
their bright colors and are responsible for many tastes associated with fruits
and vegetables. Cultures throughout the world have used flavonoids as a
source of medicine. Not only do flavonoids have medicinal uses, but they
can also be used to dye fabrics. The fastness of these dyes can be improved
with the use of a metal mordant. The purpose of this research was to try to
identify three flavonoids that have been extracted from marigold flowers
and learn about their binding interactions with metal salts. The techniques
used in this investigation include TLC, UV-Vis spectrometry and
microcalorimetry.
Photoheterotropic Marine Microbe Using HPLC
Ryan Schuh (Dr. Kevin Crawford & Dr. Arlene Haffa)
Using the marine microbe Erythrobacter sp. NAP1 as a model organism for
the aerobic anoxygenic photosynthetic microbes (AAPs) we have isolated a
blue light absorbing protein using HPLC. Based on its absorbance spectra we
hypothesize that it is analogous to the flavin protein found in the purple
non-sulfur bacterium Rhodobacter sphaeroides. If this is true then, this protein
might be responsible for organismal responses to light and pH.
The ability for an organism to survive depends upon its ability to sense and
respond to environmental changes. Anthropomorphic increases in atmospheric
CO2 are expected to acidify the oceans. Preliminary data suggests that these
organisms have enhanced growth rates under acidic conditions. We hypothesize
that if AAP growth is altered under these conditions, this protein could account
for these alterations.
The underlying mechanism behind this response could be different than in
Rhodobacter sphaeroides which become photosynthetic when in anaerobic
habitats because the AAPs which constitute 5-10% of the total ocean microbial
population3 inhabit aerobic environments. However, other work in our laboratory
suggests that the AAPs are capable of creating their own semi-aerobic growth
chambers which may allow for a similar function of this blue light absorbing protein.
for Bacterial Polysaccharides
Brian Schultz (Dr. Arlene Haffa + Dr. Brant Kedrowski)
A quantitative approach based on a previously described method for an NMR-based
Identity Assay for Bacterial Polysaccharides is being evaluated as a precise
differential tool. In the previous method, Proton Nuclear Magnetic Resonance
Spectrometry (1H NMR) was used to analyze complex mixtures of polysaccharides
precipitated using a quaternary amine followed by NaCl extraction and centrifugation
in ethanol:acetone from a series of Gram negative microbial cultures. The resulting
data appeared unique to each bacterial species and could be used to identify an
unknown. This method, however, was evaluated with a limited range of species
and reagents. Furthermore, several of its steps called for a qualitative mode of action.
Practical real-world applications of this method would require a more standardized
and systematic procedure as well as flexibility in choice of reagents and applicable
bacterial species. All four of these factors are addressed in this study. Using a
quantitative matrix for the reagents and the unknown, the procedure is tested for
optimal input values that result in a unique 1H NMR pattern with the best signal-to-noise
atio. Furthermore, the test specimens have been doubled to diversify test species as well
as to include both Gram classifications. Lastly, several different reagents are being tested
to not only keep the requirements for the method as flexible as possible, but also as to
use as much Green Chemistry as possible. The original method is rapid, simple and does
not require extensive sample manipulation. Therefore, if the standardized version
continues to function as well as the qualitative, this assay could be applied as a precision
microbial fingerprinting method.
