Abstracts are listed alphabetically by
the last name of the first author listed.
Research
SympOSIUM
INTERMOLECULAR INTERACTIONS IN PHE-NYLHYDRAZONE
Trina M. Arola
and William H. Ojala (Advisor)
Department of Chemistry
We are working toward preparing new
crystalline materials by co-crystallizing molecules we have designated
“bridge-flipped isomers.” In these isomers, two major parts of the molecule are
joined by a bridge of atoms; changing the bridge orientation relates one isomer
to the other. We are currently examining phenylhydrazones, in which the
bridge-flipped isomerism is Ar–NH–N=CH–Ar’ vs. Ar–CH=N-NH–Ar’ (where Ar =
aryl). Co-crystallization would be facilitated if the bridge-flipped isomers
were isostructural (same molecular packing arrangement). We are determining the
solid-state structures of phenylhydrazones by single-crystal X-ray diffraction
to identify isostructural bridge-flipped isomeric pairs for future
co-crystallization experiments. Intermolecular interactions linking molecules
into similar chains in the two solid isomers might encourage their
isostructuralism, so we have prepared phenylhydrazones substituted with halogen
atoms and nitrile groups to encourage intermolecular Lewis acid–Lewis base
interactions. We find H-bonding between the bridge N–H and the nitrile group to
be a competing and differentiating interaction.
INTERGENERIC HYBRIDIZATION BETWEEN THE SAND DOLLARS Encope
michelini AND Mellita isometra (ECHINODERMATA: ECHINOIDEA: MELLITIDAE)
Department of Biology
Hybridization may be viewed as
an obstacle to speciation and evolution or as a source of creative recom-bination
leading to positive adaptations. This research presents a case study of a
possible intergeneric hybridi-zation event between two groups of echinoids on
the
In 2004, research at the National Museum of Natural
History was conducted to investigate the origin of these sand dollars. Various
morphological characteristics of specimens of the presumed hybrids were
compared with those of the presumed parent taxa, Mellita isometra and Encope
michelini. Statistical analysis was not poss-ible due to the small sample
sizes; however, this study provides a broad analysis of many characteristics.
In some characteristics the hybrids fell directly within the broad limits of
variation of the proposed parents. In other cases, the presumed hybrids seemed
to be quite distinct, falling outside the range of variation of the presumed
parent taxa. Further study is required, including additional breeding
experiments, DNA analysis, and additional morphometric data sampling, including
examination of the plate structure and analysis of the internal skeleton.
WETLAND POND MACROINVERTEBRATE COMM-UNITIES ON THE ST.
OLAF CAMPUS
H. L. A. Austin and M. C. S.
Swift (Advisor)
Department of Biology
Aquatic macroinvertebrates
are invertebrates that are visible to the naked eye which live in both pond and
stream habitats. The purpose of this study was to learn to identify
macroinvertebrates, and to compile a reference macroinvertebrate profile for
ten ponds located on
EVIDENCE OF
DEPOSITION OF COMMERCIAL FERTILIZER IN AN UNPLOWED FLOODPLAIN PRAIRIE REMNANT
Elizabeth Bach and Marty Condon (Advisor)
Department of
Biology
Do unplowed areas of
remnant tallgrass prairie offer the best examples of unaltered or
"natural" prairie systems? Remnants that are on floodplains may show
evidence of human alteration even though the area has never been plowed or
intentionally altered. My project investigated the soil under Wearin Prairie, a
floodplain remnant, for evidence of alteration indirectly caused by human
actions. Specifically, my experiments were design-ned to test for the presence
of available phosphorus, a component of commercial fertilizer which might be de-posited
during flooding events. The results showed a correlation between the
concentration of available pho-sphorus and proximity of the sample site to the
MODERATION OF HUMAN RIBONUCLEASE INHIBITOR OXIDATION
SENSITIVITY BY SITE-DIRECTED MUTAGENESIS
Johann S. Bergholz, Barbara A
Hirschman, Sarah B. Miller, and Kimberly A. Dickson (Advisor)
Department of Biology
Human ribonuclease inhibitor
(RI) is a cytosolic protein critical for protecting cells from RNA degradation
by ribonucleases. With a femtomolar affinity, the binding of RI with
pancreatic-type ribonucleases is one of the strongest protein interactions
observed in nature. RI is built from highly conserved, alternating A and B
leucine-rich repeats (LRRs), each of which contains an α-helix and
β-sheet. Reduced cysteine residues contained in these repeats are critical
to protein structure but quickly oxidize under extracellular conditions,
complicating efforts to utilize RI as a laboratory reagent. Using site-directed
mutagenesis, we will mutate two highly conserved cys-teine residues at
positions 10 and 17 of the A-repeats in an effort to increase the stability of
RI. In order to main-tain molecular interactions within the tertiary structure
of RI position A10 will be replaced with a serine residue, while valine will be
substituted for the cysteine residue in position A17. Mutated proteins will be
isolated and puri-fied to ensure that structure and function have been main-tained.
PERTURBATION
OF AUXIN-MEDIATED TRAN-SCRIPTION VIA SYNTHESIS OF MOLECULAR INHIBITORS
Johann S. Bergholz, Sarah B. Miller, Ronald G.
Brisbois (Advisor), and Paul J. Overvoorde (Advisor)
Department of
Biology
Auxin, commonly
exemplified by indole-3-acetic acid (IAA), is known to play a role in plant
growth and development by affecting gene expression. The Aux/IAA family of
genes encodes short-lived nuclear proteins that can be induced within five
minutes to one hour upon exposure to IAA. The molecular mechanisms of auxin-mediated
gene expression, however, are not completely understood. Current research
points to the activation of auxin-response genes by directing proteolysis of
the Aux/ IAA family of proteins by the ubiquitin protein ligase SCFTIR1,
resulting in the activation of auxin response factors (ARFs), a known set of
transcription factors that would then arbitrate auxin-mediated gene expression.
Compound A, a furylacrylate ester of a thiadiazole hetero-cycle, has been shown
to inhibit auxin-mediated tran-scription, but neither the mechanism of action
nor the active part of this molecule are known. In this study we synthesized
different analogues of compound A to deci-pher the active core moiety of the
compound by GUS and qPCR analyses. With these results at hand, we will be able
to identify the target for compound A and gain a better understanding of auxin
functioning at the molecular level.
CREATION OF AN OXIDATION-RESISTANT RIBONUCLEASE
INHIBITOR
Owen Brafford, Catlin
Shortridge, and Kimberly A. Dickson (Advisor)
Department of Biology
Human Ribonuclease Inhibitor (RI) is a leucine-rich
repeat, horseshoe-shaped protein that binds to pan-creatic-type ribonucleases
to inhibit the degradation of RNA. The tertiary structure of RI is
characterized by repeating structural elements called A and B units. Each of
these units contains an α-helix and a β-sheet. RI contains 32
cysteine residues that create oxidative instability in the protein. Our goal
was to replace the cysteine residues with amino acids that would conserve the
structure of the protein without compromising its function. We replaced two A21
and five B21 cysteine residues with serine residues. Post-mutagenesis, the
mutant RI proteins were characterized for function and binding activity.
Possible benefits of an oxidation-insensitive RI would be as a useful
laboratory reagent and as a new tool for exploring and modulating interactions
with pancreatic-type ribonucleases.
MATE CHOICE MEDIATED BY SIZE AND CHEM-ICAL DEFENSE IN Nyssodesmus
python (POLYDES-MIDA: PLATYRHACIDAE)
Mercedes Burns and Mark A.
Davis (Advisor)
Department of Biology
Large mates are preferred in a variety of species,
presumably because larger size typically confers greater fitness. In chemically
protected species, mates may prefer more toxic partners for the same reason.
The common for-est millipede Nyssodesmus
python displays sexual dimor-phism in
body size and also produces a defensive com-pound containing hydrogen cyanide,
making it an organ-ism well suited to an experiment on mate preferences
highlighting both size and presence of defense compounds.
In research conducted as part of a study abroad course
with the CIEE Monteverde,
MICROWAVE SYNTHESIS OF IONIC LIQUIDS IN ORGANIC
CHEMISTRY LABORATORY
Nathan Burrows and David
Blackburn (Advisor)
Department of Natural Sciences
The topics of microwave synthesis, ionic liquids,
green chemistry, and neat (solventless) reactions are seldom taught in the
undergraduate laboratory setting. This lab provides a method to introduce and
experience all of these topics in a simple and easily available method.
Students produce butylmethylimidazolium bromide, a hydrophilic low-melting
ionic liquid, using a household microwave and a simple equipment setup using
common lab glassware. Students can then perform an ion exchange producing
butylmethylimidazolium hexafluorophosphate, a hydrophobic room-temperature
ionic liquid, as a liquid precipitate. Two of the 12 principles of green
chemistry, prevention of waste and atom economy, are exercised in this lab
through a neat reaction and purification method.
TURN
STRUCTURES OF A MODEL PEPTIDE SYSTEM: INSIGHTS FROM CIRCULAR DICHR-OISM
Sara J. Bush,
Kristine L. Carlson, and Kathryn A. Thomasson
Department of Chemistry
Cyclo(Gly-L-Pro-L-Pro)2 (cGPP2) is a
peptide model for cis and torsionally strained peptide bonds that exhibits a
strong distinctive UV circular dichroic (CD) spectrum. Circular dichroic
spectra were computed for the amide pi-pi* transition using the dipole
interaction model for various conformations of the peptide. Conformations of
cGPP2 were created initially from crystal and NMR data, and followed by energy
minimizations via molecular mechanics using three force fields: CVFF, CFF91,
and AMBER. A series of dielectric constants, representing various solvent
conditions from gas (0) to water (78.5), were used for the minimizations. The
minimized struc-tures were examined for structural features such as beta- and
gamma-turns. The CD spectra for each conformation were calculated using a
variety of parameters, and each result was compared with the published
experimental spectrum in acetonitrile.
STRESS FIBER FORMATION IS ESSENTIAL FOR
CELLULAR MIGRATION IN CHINESE HAMSTER LUNG FIBROBLASTS
Jenny L. Canine,
Joseph J. Provost (Advisor), and Mark A. Wallert (Advisor)
Department of Biosciences
The coordinated reorganization of the
actin cytoskeleton is a common cellular event. In a variety of cell types
including lymphocytes, the formation of stress fibers is indicative of a
stabilized attachment state where the cells no longer migrate. The research
presented here demonstrates that stress fiber formation is essential for
cellular migration in CCL39 cells, Chinese Hamster Lung fibroblasts. As in
virtually all other mammalian cells, the Sodium–Hydrogen Exchanger (NHE) is
present and plays a dual role in pH regulation and cytoskeletal attachment to
the plasma membrane. In this second role, NHE is also essential for the
formation of stress fibers in cells. Previous research from our laboratory has
shown that phenylephrine (PE) stimulates NHE and induces stress fiber formation
in these cells. To investigate the role of stress fiber formation, CCL39 cells
were allowed to grow into a confluent monolayer in a 35 mm culture dish. The
cells were then serum deprived 12 to 18 hours. At this point the monolayer was
wounded using a standard cell scraper. The cells were then allowed to migrate
into the wounded area for 24 hours in one of four conditions: serum-free media,
serum-free media with PE, 10% serum media, and 10% serum media with PE. Our
data show that in PE-stimulated CCL39 cells, stress fibers are present in the
cell immediately adjacent to the wound area and in cells that have migrated
into the wound. These studies indicate that stress fiber formation has a direct
involvement in cell migration.
STRUCTURAL INSIGHT FROM
CIRCULAR DICHROISM
Kristine
L. Carlson, Mark R. Hoffmann, and Kathryn A. Thomasson
Department of Chemistry
The tricyclic structure
of the substituted diketo-piperazine cyclo(L-Pro-L-Pro) constrains its possible
geo-metric conformations to three minimum energy structures. The relationship
of these three structures was examined via comparison of UV circular dichroic
spectra calculated using the classical dipole interaction model with experi-mental
CD (Bowman, R. L.; Kellerman, M.; Johnson, W. C., Jr. Biopolymers 1983, 22, 1045). Starting with crystal structure data for the platter
conformation, the three conformations were obtained by geometric optimization
using MP2, DFT, and three molecular mechanics force fields. The pi-pi* spectrum
produced by each conform-ation was distinct but followed a pattern with a
negative band at ~ 185 nm and a positive band at ~ 210 nm.
The CFF91 force field
was the only classical force field to produce structures whose composite CD
resembled experiment, but conformations were not clearly defined by CD due to
the high (~ 20 degrees) amide bond torsion angles. Inclusion of water as
solvent in the class-ical optimizations through the use of a dielectric
constant resulted in very small changes in geometry for each con-formation and
little or no shift in weighted CD, although the energies obtained using the
CFF91 force field permit-ted real occupation of the chair and boat
conformations (18% and 31%, respectively). DFT and MP2 energy calc-ulations
indicated that the population of the molecule in the three conformations is
roughly equal (MP2: 34% platter, 33% chair, 33% boat). Boltzmann-weighted
composite CD supported this conclusion through accurate description of the two
pi-pi* peaks with respect to one another.
SOY PROTEIN ISOLATE
Michelle Caron
and Gina Mancini-Samuelson (Advisor)
Department of Chemistry
The purpose of this project is to develop
a case study for the Advanced Analytical class that focuses on the High
Performance Liquid Chromatography instrument. The project focuses on the
isolation of Soy Protein Isolate, 11S, and 7S protein from soy flour and
other soy products.
MOLECULAR ANALYSIS OF A TRANSCRIP-TIONAL SILENCER IN Drosophila melanogaster
Chris Chamberlain and Presley
Martin (Advisor)
The MM-50 transgenic line of Drosophila melanogaster contains a D. melanogaster Alcohol dehydrogenase (Adh) transgene inserted at
position 25C of chromosome 2. Previous analysis has shown that expression of
this Adh transgene is inhibited by a silencing activity located in an 1180 b.p.
region near the 51 end of the inserted gene. The sequence of the
silencer region revealed the existence of two 20 b.p. homologies, which have
been shown to inhibit Adh expression by 50%. The objective of this
investigation was to determine what other sequences within the silencing region
are required to produce the near 100% inhibition of expression observed when
the whole region is present. Seven unique fragments of the silencer sequence
were cloned using PCR and purified using standard procedures. Two fragments
contain the first homology of the sequence, one fragment contains the second
homology, and four fragments contain neither of the homologies. Each of the
seven fragments were transformed into plasmids containing a functional Adh
gene, thus yielding seven complete plasmids, each containing one of the
fragments and one copy of the Adh gene. Each plasmid will be injected into Drosophila embryos and the larvae will
be assayed for the level of Adh gene expression.
THE EFFECTS OF OPIOID ANTAGONIST NAL-TREXONE IN
ANIMALS MOTIVATED TO EAT BY TASTE
Munya Chimukangara and Tim
Shaw (Advisor)
Department of Biological Sciences
It is well known that the opioid system plays a
significant role in the regulation of palatable food intake. Generally
speaking, opioid agonists increase feeding while opioid antagonists decrease
feeding in non-food-restricted animals. These drugs, however, have a substan-tially
reduced effect in food-deprived animals. These data are based predominantly on
studies performed on the peripheral opioid system. Not much is known about the
effects of these drugs when administered into the opioid receptors of the
central nervous system. However there are data suggesting that food intake
regulation is also dependent on brain sites in the hypothalamus. The hypo-thalamus
is known to have nuclei associated with energy-and-reward-related feeding. In
this study I was therefore trying to find out if the administration of
Naltrexone in the hypothalamic paraventricular nucleus (PVN) would decrease
food intake more effectively in a food-restricted (energy needs-related) model
than in a non-food-restricted (reward-related) model. My results suggest that
Naltrex-one more effectively decreases intake of food in the food-restricted
model than in the non-food-restricted model. The data also suggest that the PVN
is primarily involved in energy-needs-driven-food intake in comparison with
reward-driven food intake.
ANALYSIS OF
THE EXTRACELLULAR HEMO-GLOBIN FROM Lumbriculus variegatus
Jessica Curtis, Rebecca Derby, Melissa Seefeld, Lee
Vang, and Kay Tweeten (Advisor)
Department of
Biology
The major carrier of
oxygen in the
The hemoglobin was
isolated from homogenates of worm tissue by ultracentrifugation and size
exclusion chromatography. The morphology, subunit composition, and size of the
hemoglobin were determined by electron microscopy and showed that the structure
consisted of two hexagonal-shaped rings that were 265 Ĺ in width and composed
of six subunits each. Western blot analysis showed that antibodies against
human hemoglobin bound to four of the proteins with molecular weights of
14,900, 15,300, 16,100, and 16,500 daltons, suggesting these are the
oxygen-binding proteins. Five to six potential linker proteins with molecular
weights ranging from 26,200 to 36,000 daltons were also observed. The
glycoprotein composition of L. variegatus hemoglobin appeared to be
more complex than that of earthworm hemoglobin with all four oxygen-binding
proteins and the predominant linker protein being glycosylated. Hemoglobins
from L. variegatus and Lumbricus terrestris were compared by
two-dimensional gel electrophoresis to further evaluate the similarities and
differences in the proteins composing these assemblages.
THE GENDER GAP IN EARNINGS: DOES URBAN LOCATION
MATTER?
Amanda Demeules and Marsha
Blumenthal (Advisor)
Department of Economics
Dating back to ancient
times one can find references and data pointing to women not earning as much as
men. In fact Leviticus (27: 3–4) states that a woman is worth 30 shekels of
silver and a man 50 shekels of silver. This paper aims to explore the modern
gender gap in earnings in midwestern
states, specifically, examining the influence of metropolitan location.
Individual data from the Current
Population Survey will be used to construct an
PROJECTIONS OF RVM NEURONS TO PAIN-RELAY SITES
David H. Do and Martin W.
Wessendorf (Advisor)
Department of Neuroscience
Pain, which warns the body of potentially harmful
stimuli, could hinder one’s ability to act protectively in dangerous
situations. It is speculated that, during a “fight or flight” response, neurons
in the rostral ventromedial medulla (RVM) of the brainstem send inhibitory
signals down the spinal cord to block trans-mission of pain. Activation of m-opioid receptors in the RVM by drugs such as morphine
and heroin utilize these pathways to regulate pain in much the same ways. In
contrast, in the case of neuropathic pain, RVM cells appear to work in an
excitatory manner to enhance nociception. These phenomena are well documented,
but the mechanisms by which they occur are less understood.
The RVM is populated by cholinergic (ChAT) and
serotonergic (5-HT) neurons, among others. These neurons, which signal via the
neurotransmitters acetyl-choline and serotonin, respectively, may play a key
role in pain facilitation by preventing or amplifying signals relayed by
neurons in the spinal cord. In this experiment, the potential role of these RVM
neurons in pain modula-tion was examined by finding neural connections to the
dorsal horn and the spinal trigeminal nucleus, two regions of the nervous
system where peripheral sensory information is integrated.
GENETIC SCREEN OF
SECRETION MUTANTS IN Chlamydomonas
Dina
Dobraca, Milkeesso Foge, Srividya
Gainedi, Sarah Merkel, Paul Sarjo, and
Anton Sanderfoot (Advisor)
Department of Plant
Biology
Secretion is an
essential activity that plays important roles in numerous cell functions, such
as cell-to-cell communication, waste disposal, and cell defense. The purpose of
this project is to characterize previously unidentified genes involved in
secretion in the model organism Chlamydomonas
reinhardtii, a unicellular haploid green alga. We expect that Chlamydomonas will be a useful model
organism for characterizing secretion mutants because only one gene copy of the
haploid organism needs to be mutated for the strain to have a mutant phenotype
and the unicellular plant may survive with defects that may be lethal in
complex, multicellular plants.
Using a forward genetic
approach, a collection of mutant strains will be screened for secretion defects
using an endogenous secreted enzyme as a primary screen. A secondary screen
will use a synthetic, secreted green fluorescent protein (GFP) construct to
confirm secretion defects and to determine the location of the blocked
secretion product. Briefly, wild-type Chlamydomonas
will secrete the GFP extracellularly; in a mutant with a secretion blockage,
the GFP will accumulate inside the cell at the point of blockage. We are at the
stage of creating and confirming the expression of the fluorescent protein
constructs. In the future, we hope to use these tools to identify plant-specific
secretion genes in Chlamydomonas and
apply these results to multicellular crop plants.
Readability
Levels of High School and College Chemistry Textbooks
Elizabeth A.
Drommerhausen and Dr. Jeffrey R. Pribyl (Advisor)
Department of Chemistry and Geology
In many science classes the textbook is
frequently the determining factor for the content of a course. This is
particularly the case where chemistry education is concerned. Just how
effective is that heavy, expensive tool? While textbook content is critical,
another factor just as critical is often overlooked. That factor is the reading
level, also known as the readability level. Chemistry textbooks typically are
written at a reading level that is well above secondary students’ or college
students’ abilities. Numerous high school and college chemistry textbooks were
analyzed for their readability level using the Fry and Raygor readability
graphs. The results of this work confirm that the readability level of
chemistry textbooks is often times well above the reading level of the target
audience.
THE INVISIBLE HAND OF NATURAL SELEC-TION: SMITH,
John Dukich and Mark Borrello
(Advisor)
Department of Ecology, Evolution and Behavior
Although Adam Smith published The Wealth of Nations in 1776 and Charles Darwin published The Origin of Species in 1858 their
ideas have had a profound impact on modern thought. How have these two ideas,
in the context of eighteenth- and nineteenth-century thought, helped to create
the global gap between the wealthy and the poor? Smith and Darwin, as well as
other thinkers of their time, were influenced by contemporary society and
ideas. These ideas, of reductionism, mechanism, and scientific materialism,
have been inherited by modern science and modern societies, which in turn have
shaped how humanity perceives itself and what’s expected of itself. After
putting Smith and Darwin in historical con-text, I argue that such a wide gap
between the wealthy and the poor has arisen, in part, due to misinterpretations
of their respective works as well as due to the inherited ideas of the past 300
to 400 years. I conclude with what is necessary to overcome these obstacles and
the implications this would have.
ERK ACTIVATION BY PHOSPHOLIPASE D THROUGH
THE α-1 ADRENERGIC RECEPTOR IS Ras DEPENDENT
Matthew P. Duval,
Joseph J. Provost (Advisor), and Mark A. Wallert (Advisor)
Biosciences Department
Phospholipase D (PLD) is considered an
important signaling molecule in many growth factor pathways. PLD converts
phosphatidylcholine into choline and phosphatidic acid (PA). The PA generated
by PLD is thought to recruit Raf to the lipid rafts of cell membranes, leading
to stimulation of growth factor signaling com-plexes. Previous experiments in
our laboratory have shown the addition of primary butanol inhibits ERK
activation by blocking PA production. While this work suggests that PLD is
involved in the activation of the ERK signaling pathway, it does not explain
its mech-anism. To investigate the role of PLD in ERK activation, two
short-chain, cell-permeable phosphatidic acids
(1,2-Dihexanoyl-sn-Glycero-3-Phosphate and 1,2-Dilauroyl-sn-Glycero-3-Phosphate)
were incubated at several times and concentrations with CCL39 fibroblasts. Both
short chain phosphatidic acids (scPA) act as endogenously added PLD product.
Both the 6 and 12 acyl scPA stim-ulated ERK activation in a dose- and time-dependent
manner with maximum ERK activation observed with the 6 acyl scPA. Ras
activation pull down assays conducted with phenylephrine (PE) stimulating cells
showed Ras activation. When a primary butanol was added prior to stimulation,
PE did not activate Ras. Additional evidence for a Ras-dependent PLD-ERK
activation was determined through dominant negative Ras (D/N Ras). Expression
of D/N Ras blocked activation of ERK by PE. The ability of D/N Ras to inhibit
PA activation of ERK was also invest-igated. This is a novel mechanism for PLD
involvement in growth factor pathways. This work was supported by a grant from
the NIH, Award number 1 R15 HL074924-01A1.
SEQUENCE AND EXPRESSION OF THE FGF-10 GENE IN Xenopus
laevis LUNG DEVELOPMENT
Brett D. Einerson and Brian
Hyatt (Advisor)
Department of Biological Sciences
During lung bud morphogenesis, reciprocal interactions
between the epithelial endoderm and the mesenchyme surrounding it lead to early
branching of the pulmonary system. Members of the fibroblast growth factor
(FGF) family, along with their receptors, have been shown to play an integral
part in mediating these inter-actions. FGF-10 specifically has been shown to be
an essential regulator in lung formation. The FGF-10 gene was isolated from Xenopus laevis, and its expression
during lung development was examined. X.
laevis serves as an effective model organism for this study. Gathering
information about gene expression in this organism expands our understanding of
pulmonary development.
ANALYZE THIS! A CASE STUDY APPROACH IN THE
ANALYTICAL CHEMISTRY LABORATORY
Sarah Evans, Gina
Mancini-Samuelson (Advisor)
Department of Chemistry
If one contemplates art and science for a minute,
artists are really quite similar to chemists.
Both are personally engaged in combining, transforming, and
experimenting with materials. In my
personal opinion, the relation of art to chemistry is, in fact, the most overt
among all the scientific disciplines.
This research project incorporates art with chemistry creating that
unforeseen bond. In this project, a case
study was created for the use in Advanced Analytical Chemistry course at the
A SPECTRAL ANALYSIS TEST OF THE FEMALE MIMICRY
HYPOTHESIS OF DELAYED PLUM-AGE MATURATION
Ben
Freeman and Mark A. Davis (Advisor)
Department of Biology
Delayed plumage maturation (DPM) in birds is the
retention of subadult plumages by individuals of one sex when sexually mature.
The female mimicry hypo-thesis of DPM suggests that subadult males are selected
to mimic females in appearance, as has been demonstrated in animals from
insects to lizards, and in adult males of one bird species (Langmore et. al.
1999). Additionally, the female mimicry hypothesis has been suggested to apply
more widely to birds with DPM and female-like subadult plumages. A
full-spectrum analysis of two bird species with the above characteristics,
painted buntings (Passerina ciris) and American redstarts (Setophaga
ruticilla), revealed at least one distinguishing plumage patch in P.
ciris and none in S. ruticilla. The distin-guishing plumage patch in
P. ciris was the lower back, which could be a concealable badge.
Thus, the female mimicry hypothesis could, at least from this spectral
perspective, apply to both species.
THE ROLE OF 5-HYDROXYTRYPTAMINE (5-HT) AND
THE 5-HT1A RECEPTOR IN HUMAN T CELL PROLIFERATION
Audrey Geiger,
Melinda Hexum, Kate Ruter, and Dr. Jodi Goldberg (Advisor)
Biology Department
Previous research has shown that the
neurotransmitter serotonin, or 5HT, is necessary for T cell proliferation.
However, these studies have employed heterogeneous culture systems. In
order to determine the specific impact of 5-HT on human T cell proliferation, T
cells were first purified from whole blood to greater than 98% purity. T cells
were then labeled with a fluorescent dye and active-ted in one of two manners.
T cells were activated in the absence of other cells by incubating purified T
cells with anti-CD3/anti-CD28 coated beads (accessory cell inde-pendent
activation). Alternately, T cells were activated in the presence of
accessory cells and the T cell mitogen phytohemagglutinin (PHA), a plant lectin
(accessory cell dependent activation). The role of 5-HT in this
activation was assessed by either adding the 5-HT synthesis inhi-bitor pCPA or
by adding 5-HT receptor antagonists to the cultures. Flow cytometry was
used to measure T cell proliferation as a decrease in T cell associated fluor-escence.
Inhibition of proliferation by pCPA was observ-ed at a lower concentration in
accessory cell dependent cultures than in accessory cell independent cultures.
Inhibition by Methiothepin, a general 5-HT receptor antagonist, was observed in
cells stimulated by both accessory cell dependent and accessory cell
independent methods at equal concentration. No inhibition by Nan-190, a
specific 5-HT1A receptor antagonist, was observ-ed. Reversal of inhibition of T
cell proliferation in these cultures by the introduction of 5HT into the cell
cultures has not yet been achieved.
STRUCTURAL STUDY OF ALPHA-AMYLASE:
SELECTION OF SCAFFOLDING STRUCTURES AND DOMAIN SWAPPING
Robyn Gilbertson
and Paul Tavernier (Advisor)
Department of Chemistry
The structure of Bacillus licheniformis alpha-amylase was studied by viewing its pbd
file 1BLI with Rasmol. The 11th alpha-helix was selected for use in
this project. Similar sequence helices were found using online bioinformatics
databases such as Conserved Domain Database and Protein Data Bank. An
alpha-helix in hydro-lase from Pseudomonas
stutzeri was selected for the domain swap. Stratagene's QuikChange II
Site-Directed Mutagenesis Kit was used to delete the 30-base-pair DNA sequence
coding for the selected alpha-helix from AmyE, the gene for alpha-amylase in B. licheni-formis. Plasmid pRL298
containing AmyE was the DNA template used for the mutagenesis. Using the
successful deletion plasmid, the DNA sequence for the P. stutzeri helix was inserted using the QuikChange Kit. Results
were verified by growth on LB agar plates containing kanamycin and starch and
by molecular weight deter-mined by gel electrophoresis.
AdS_2 SOLITON
DYNAMICS
Kassahun Haileyesus and Tonnis Ter
Veldhuis (Advisor)
Department of
Physics and Astronomy
The dynamics of a
soliton in a two-dimensional curved space-time is worked out. Transformation
rules in AdS_2 space are found and Maurer Carton one forms are used to
construct a Lagrangian that is invariant under AdS_2 transformations. This
Lagrangian is shown to be equivalent to the Lagrangian of a relativistic
Harmonic oscillator. Conserved quantities associated with symme-tries are found
using Noether's method and they are used to find solutions to the Euler
Lagrange equations of mo-tion. From the invariant action, the conjugate
momentum is determined and the Hamiltonian is constructed. This Hamiltonian is
then shown to be equivalent to that of a conformal mechanics in one dimension.
THE EFFECTS OF LIPOPHOSPHOGLYCAN STIMULATION ON
MACROPHAGE GENE EXPRESSION
Cassondra Halsted and Joyce
Doan (Advisor)
Department of Biology
Leishmania spp. are protozoan parasites which are transmitted by
sandflies or, to a lesser extent, by the sharing of needles. Leishmania parasites are found all over
the world, although infection with these organisms is much less common in the
EFFECTS OF
NEUROTENSIN ON THE SMOOTH MUSCLE TISSUE OF THE
MOUSE UTERUS
Nellie Hangge and Teresa
DeGolier (Advisor)
Department of Biology
Research has shown neurotensin (NT), a biolog-ically
active peptide, to produce various effects in mam-malian smooth muscle tissue.
NT inhibits rat intestine yet stimulates guinea pig colon. This study
investigated whether NT would have an effect on smooth muscle tissues of the
isolated mouse uterus. Oxytocin was used as a positive control for uterine
contraction. Uterine horns from mice in the diestrus stage of the cycle that
were suspended in the smooth muscle bath and subjected to higher doses of NT
(10-7-10-6M) increased contractile frequency. Oxytocin caused an increase in
strength of contraction within tissues from mice in estrus at these same doses.
These results suggest that NT may play a role in uterine contraction during
diestrus and, therefore, mouse reproduction.
DESIGN AND SYNTHESIS OF TRPV1 ANTAGON-ISTS:
PROBING THE D-REGION BINDING SITE USING AMIDOALKYL SUBSTITUENTS
Victoria D. Held
and David B. Rusterholz (Advisor)
Department of Chemistry
University of Wisconsin–River Falls,
TRPV1 (transient receptor potential
vanilloid subfamily 1) is a membrane-bound ion channel protein that mediates
the pain response elicited by capsaicin, resiniferatoxin, and similar
drugs. Structure activity studies of
compounds that bind to TRPV1 indicate several binding sites, namely: (1) an
aromatic “A” region, (2) a polar “B” region, and (3) a hydrophobic “C” region. Recently a fourth region has been proposed
based on the structure of resiniferatoxin. This fourth “D” region is thought to
be responsible for the high potency exhibited by resiniferatoxin. A new series
of potential TRPV1 antagonists was designed that incorporates molecular
features intended to interact with the known A, B, and C binding sites. In
order to investigate the interaction of the D binding region, amidoalkyl groups
were incorporated into the target structures. The synthesis of several of
members of the target series was accomplished using a convergent synthetic
strategy. Ultimately these compounds will be tested for their effectiveness as
TRPV1 antagonists.
THE EFFECTS
OF INHIBITION OF SEROTONIN SYNTHESIS ON T CELL PROLIFERATION
Melinda Hexum, Audrey Geiger, Katelyn Ruter, and Dr. Jodi Goldberg (Advisor)
Department of
Biology
Previous research has
indicated that serotonin (5-hydroxytryptamine, 5HT) is a signal necessary for
human T cell proliferation. The role of 5HT in T cell prolifer-ation was
investigated by examining the impact of p-chlorophenylalanine (pCPA), a
serotonin synthesis inhib-itor, on the proliferation of purified human
peripheral blood T cells activated by accessory cell independent (anti-CD3/CD28
beads) and accessory cell dependent (phytohemagglutinin, PHA) methods. T cell
proliferation in response to either method of activation was inhibited by pCPA,
though T cells activated by PHA and accessory cells were inhibited at
significantly lower doses than pure T cells activated with antibody-coated
beads. Inhibition of proliferation with
pCPA was most effective when added upon initiation of T cell activation, with
inhibitory effects progressively reduced when pCPA was added on day 1 or 2
after activation. Attempts were made to reverse the inhibitory effects of pCPA
on T cell proliferation by providing pCPA treated cells with exogenous 5HT or
5-hydroxytryptophan (5HTP), but neither restored prolifer-ation at any
concentration tested. These data suggest that T cells are inhibited by pCPA,
but that non-T cells may be more sensitive to pCPA’s effects. It remains to be
determined if the inhibition occurs via a serotonin-dependent pathway.
GAS CHROMATOGRAPHY DETECTION OF TERBUFOS
Cori Hollingsworth, Ian
MacRae, and Julie E. Larson (Advisor)
Department of Chemistry
Terbufos, an active ingredient in granular pesticide
(Counterâ-BASF), is applied to
cultivated soil in
SEX SELLS: THE ECONOMICS OF PROSTITU-TION
Anna C. Hovde and
Fahima Aziz (Advisor)
Department of Management and Economics
Prostitution is illegal in most countries
of the world, but the market for paid sexual services still flour-ishes. The
United Nations estimates that prostitution is a $7 billion-a-year industry.
Prostitution is openly adver-tised in many local newspapers, and street
prostitutes can be seen in major cities even where prostitution is illegal.
This study examines why the market for sexual services exists and the costs it
imposes on society. The supply and demand sides of the
EXPERIMENTAL INVESTIGATION OF AN ELEC-TROPHILIC
AROMATIC ADDITION REACTION
Michael Huehn and Jack Waas
(Advisor)
Department of
In 2005, Chi and coworkers reported an unusual
electrophilic aromatic addition reaction (AdEAr) (Choi, H. Y.;
Srisook, E.; Jang, K. S.; Chi, D. Y. J.
Org. Chem. 2005, 70, 1222-1226). The AdEAr
and electrophilic aromatic substitution (EAS) pathways share a common initial
mechanistic step. After one electrophilic aromatic bromination of the usual
variety, the addition of a second bromine is thought to proceed with further
addition of methanol rather than deprotonation. This addition of methoxy is
observed only under basic methanolic condi-tions, and requires either a
pyridine moiety or added pyridine. This is contrary to what is normally
observed under acidic or neutral conditions which result in EAS only. Our
initial results indicate that the report of the AdEAr occurs in the
manner reported by Chi and cowork-ers. These results are based on experiments
performed on naphthalene and quinoline derivatives. Chi and coworkers reported
their experimental results but did not report any computational results. Our
preliminary semi-empirical and DFT calculations compare reaction energies of AdEAr
with those of EAS. Our research will contribute to the advancement of organic
chemistry and have possible applications in pharmaceuticals.
SULFONATION
OF COMPLEX BIOMOLECULES BY THE BIOCATALYTIC TRANSFER OF SULFINYL DERIVATIVES
Tuere A. Hughes, (Romas J.
Kazlauskas), Christopher K. Savile, and Paul F. Mugford
Department of Biochemistry, Molecular Biology, and
Biophysics
Sulfate groups on
complex biomolecules in nature, such as hormones, sugars, and aminoglycans,
play a key role in their physiological function. These sulfate groups are
essential in hormone regulation, cellular degradation, blood coagulation, and
cell–cell recognition processes such as cell adhesion, developmental cell
signaling, bacterial and viral pathogenesis, and tumor metathesis. A major
barrier to determining the structure–function relationships of sulfate groups
in biology is the great difficulties in the chemical and biochemical syn-theses
of complex sulfonated biomolecules and analogs. Chemical methods cannot select
among the many groups with similar reactivity in a complex biomolecule, and
biosynthetic methods that mimic natural biosynthesis yield only trace amounts
of products. We propose to use unnatural reactions coupled with biocatalytic
methods to overcome these difficulties. The use of enzyme catalysis will
provide the advantage over chemical methods by showing selectivity for specific
groups. The use of unnatural reactions and conditions will allow for the
production of large amounts of desired products.
Our aim is to identify proteases and sulfinyl group donors for the
biocatalytic synthesis of complex biomolecules containing sulfates. Our
working hypothesis is that sulfinyl groups are similar enough in structure and
chemical reactivity to acyl groups, that proteases that normally transfer acyl
groups will also transfer sulfinyl groups. We propose
a two-step method involving an initial protease-catalyzed addition of a
sulfinyl group, followed by chemical oxidation to a sulfate. We synthe-sized
and tested the enzymatic hydrolysis of dibenzyl sulfite and diphenyl sulfite by
reacting with six proteases: subtilisin Carlsberg, subtilisin BL, pronase,
pepsin, alpha-chymotrypsin, and penicillin acylase.
ECOLOGICAL
GENOMICS: ANALYZING GENE-TIC DATA FROM Marchantia USING ISSRs AND THE CEQ 8000
Eun
Hyuk Chang, Linda Fuselier (Advisor), and Michelle Malott (Advisor)
Biosciences Department
Ecological genomics is an
emerging field at the interface of ecology, evolutionary biology, and genomics.
The application of genetic information such as genome structure, DNA sequence,
DNA variation, and gene function is helping researchers better understand the fundamental
mechanisms of evolutionary and developmental biology.
This, in turn, contributes to our understanding of
the ecology of a variety of organisms.
Most genomic applications
involve isolation of DNA, polymerase chain reaction (PCR) amplification of specific
regions of DNA, and the analysis of the resulting amplification products in a
manner relevant to the question being asked. For example, examining the DNA
sequence and determining the amount of genetic diversity of a population of
organisms can be helpful in addressing questions involving reproductive
behaviors, evolutionary changes, and overall health of the species.
Traditionally, analysis of amplification products is done by gel
electrophoresis and visual scoring of gels. This can be a time-laborious
process when attempting to analyze many samples (i.e., different individuals) from different sample sites or
locations in a statistically meaningful manner. This poster describes the use
of a new instrument, the CEQ 8000, at MSUM for examining the genetic diversity
of Marchantia species.
IS THERE A ROLE FOR Rap1 IN THE MAMMAL-IAN
CELL CYCLE?
Andrea Johnson
and Jennifer L. Cruise (Advisor)
Department of Biology
The small G-protein Rap1 has been linked to a number of signaling pathways involved in the cell cycle, but its exact role is unknown. Prior research demonstrating that endogenous Rap1 expression is down-regulated prior to the onset of DNA synthesis has led to the hypothesis that Rap1 activity regulates the cell cycle. We are testing the predictions that increasing active Rap1 in cells would decrease DNA synthesis and cell proliferation, and decreasing active Rap1 would increase DNA synthesis and cell proliferation, using mammalian MRC-5 (fibroblast) and MDCK (epithelial) cells. These cells were transfected transiently or stably with either an activated Rap1 gene, a control plasmid, or a dominant-negative Rap1 gene. The cell cycle was then monitored through flow cytometry, BrdU labeling index assays, and cell counts using a hemacytometer. Flow cytometry experiments and BrDU labeling studies thus far have suggested that active Rap1 reduces baseline DNA synthesis and response to growth factor stimulation. Dominant-negative Rap1 appears, at least to some extent, to have the opposite effect, increasing baseline DNA synthesis and response to growth factors. In addition, cell counts in MDCK stable cell lines reveal a higher overall proliferation rate in cells expressing dominant-negative Rap1, and a lower rate in cells expressing increased active Rap1, when compared with