2015 Fall Undergraduate Research Student Poster Forum (9th)

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Effect of Transmission Electron Microscopy Sample Preparation Methods on Nano Structure and Properties of Metallic Glasses
(2015-09-17) Park, Gyuchul; Hwang, Jinwoo
Metallic glasses (MGs) are new metallic alloys with excellent mechanical properties. However, practical applications of MGs are still limited due to the lack of understanding on their atomic structure. Since MGs have disordered atomic structure, it is difficult to obtain the structural information that directly connects to their important properties. Recently developed transmission electron microscopy (TEM) techniques, such as fluctuation microscopy, opened new possibility in understanding the structure-property relationships in disordered materials. However, it is important to understand the effect of the TEM sample preparation methods to the structure and the quality of the samples. In the present work, we demonstrate that the structure of the MG TEM samples can change depending on the sample preparation methods. We show that the samples prepared using mechanical polishing changed its structure, while the samples prepared using focused ion beam (FIB) showed no apparent structural change. FIB method also had other benefits, including faster preparation time and high success ratio. However, concerns still remain because FIB is known for damaging the surface of the samples, and the extent of the surface damage is difficult to quantify in disordered materials, such as MGs. Regardless, we conclude that FIB is the most efficient and reliable technique for MG TEM sample preparation. On the other hand, since mechanical polishing makes the material plastically deformed, it may be useful for studying the nanoscale deformation behavior of MGs.
Consequences of an NFU1 Mutation in the Fe-S Cluster Biosynthetic Pathway
(2015-09-17) Wesley, Nathaniel; Wachnowsky, Christine; Fidai, Insiya; Cowan, James
Fe-S clusters are prosthetic groups found in several metalloproteins, and are conserved across all kingdoms of life (Lill, 2008). These clusters have essential yet diverse roles in the mechanics of the cell, including electron transfer, regulation of gene expression, and disulfide reduction (Johnson, 2005). Mutations in cluster-assembly and transfer proteins dramatically affect several crucial metabolic pathways (Ahting, 2015). Genetic mutations to a specific subset of mitochondrial cluster-delivery proteins are broadly categorized as a Multiple Mitochondrial Dysfunction Syndrome (MMDS), and symptoms include impairment of neurological development, lactic acidosis, failure to thrive, and ultimately early death (Invernizzi, 2014) (Navarro-Sastre, 2011). Multiple Mitochondrial Dysfunction Syndrome 1 (MMDS1) arises as a result of the missense mutation c.622G>T in NFU1, a cluster scaffold protein, which mutates a glycine near the Fe-S cluster binding pocket to a cysteine (G208C) (Navarro-Sastre, 2011). The connection between the mutation in NFU1 and MMDS1 has been recently discovered, and at this point, little is known about the role of NFU1 and why the point mutation results in such drastic consequences. A better understanding of the mechanism of disease and the dysfunction of the mutant NFU1 at a fundamental level is essential in order to find a potential cure. An investigation into the structural and functional consequences of an additional cysteine residue at the binding pocket will serve to characterize the mutant protein and examine the cause of disease at a biochemical level.
Developing an in vitro myobundle model system for pathophysiological studies of human skeletal muscle
(2015-09-17) Sherry, Aubrey; Weisleder, Noah
Existing in vitro models for liver, lung, and cardiac tissue have made recent notable progress, however a predictive model of human skeletal muscle does not exist. While, two-dimensional cultures of myoblasts are well known, these cultures lack the organization and function of a native muscle. Therefore, the usefulness of these existing models in pharmacological studies and disease modeling is limited. The purpose of this study is to adapt a novel three-dimensional skeletal muscle model and confirm that it is usable in future studies. This will be done by creating custom silicone molds and teflon frames in which various myoblast cell lines and myocytes derived from human PSCs will be cultured. Thus far, attachment to the frame has been observed but cell death has soon followed. Our solution is to proceed to vary the cell type and concentration in order to find cells for optimal growth in the three-dimensional matrix. Our observations do prove, however, that formation of the myobundle is possible with this model and that with continued alteration the myobundle should survive for use in further testing. Ultimately, these fabricated three-dimensional myobundles should be electrically and chemically responsive and are reported to contract spontaneously. Use of human iPSCs cells will allow for production of human muscle cells and will also allow generation of patient specific cells that can harbor mutations leading to disease states, such as muscular dystrophy. A physiologically correct in vitro skeletal muscle model can provide a tool for pharmacological testing and an alternative to animal studies, mitigating ethical considerations and reducing the number of in vivo and ex vivo models.
Synthetic Approach to Realkyation of Aged Acetylcholinesterase Using Quinone Methide Precursors
(2015-09-17) Rao, Harsha; Hadad, Christopher M.
Organophosphorus (OP) nerve agents are a class of toxic compounds that inhibit acetylcholinesterase (AChE), an enzyme that catalyzes the conversion of acetylcholine to choline at neurosynaptic junctions. OP inhibits AChE by binding to the active site and this undergoes a subsequent irreversible process called aging, where the OP-AChE adduct is dealkylated. This results in the accumulation of excess acetylcholine in the central nervous system that causes significant nerve damage. Current oxime-based pharmaceutical agents, such as 2-PAM, used to treat inhibited AChE are ineffective on aged AChE. Previous studies have shown that quinone methides (QM) are alkylating agents and these could potentially reverse the aging process through a kinetically favored realkylation mechanism. In the past, we have designed and synthesized a library of QM precursors. Our research focuses on the analysis of these alkylating compounds and investigating their ability to realkylate model phosphonate.
Eddy Current Microscopy for Detection of Solid Tumors
(2015-09-17) Javor, Josh; Subramaniam, Vish
Optical microscopy is commonly used to investigate observable characteristics in biological tissue. A method will be presented to image electrical properties of tissue using known engineering techniques that will complement conventional histopathology. Eddy current detection involves measuring the electrical properties of a conductive sample in the presence of a time-varying magnetic field. Biological tissue has a small but nonzero conductivity and so a precise signal filter is needed to detect small changes in the shape and size of tiny current paths (eddy currents) in the sample. Characteristics of abnormal tissue such as morphology, macromolecule concentration and ion transport contribute to varying electrical properties in a biological sample. Detecting and quantifying these characteristics on the order of micrometers has the potential to improve the staging and diagnosis of disease. The development of the proposed device will be described as well as the future plans to validate using a wax phantom, porcine tissue, and surgically excised human tissue.
Probabilistic Evaluation of Carbonation Induced Deterioration in Prestressed Concrete Structures
(2015-09-17) Loos, Sabine; Shafieezadeh, Abdollah
Reinforced concrete is one of the most universally used building materials, since it has a high capacity under compression, handles tensile stresses through steel reinforcement, and provides lasting durability. This durability, however, is reduced by a form of deterioration, called carbonation, caused by the reaction of carbon dioxide with the constituents inside concrete. This form of deterioration alters concrete’s material properties by increasing the compressive strength, but reducing its deformation ability. Moreover, when carbonation is coupled with chloride penetration, it destroys the natural concrete protection surrounding reinforcing steel. These alterations decrease the structural capacity of concrete members by increasing the likelihood of brittle failure and reducing the steel cross-sectional area. Carbonation is expected to be of increasing concern for structural engineers, because deterioration can lead to premature failure before the intended design life. The purpose of this study is to assess the impact of concrete carbonation and chloride penetration on the service life of reinforced concrete structures and to evaluate the probability of structural failure with respect to design and environmental exposure. Since carbonation is a stochastic phenomenon with highly variable properties, a probabilistic model is developed to determine the time to corrosion initiation, which required a comprehensive literature review of previous models and experimental research . Previous models have analyzed this rate at the material level, focusing on maintenance rather than structural reliability. However, this study extends the effects of carbonation past the serviceability to the durability level by integrating the carbonation progression into a finite element model of a prestressed concrete pile. With the increasing amount of atmospheric carbon dioxide, concrete carbonation is expected to reduce future durability of concrete infrastructure. It is expected that this research will provide more information on whether current concrete design standards provide adequate structural reliability with the expected deterioration caused by concrete carbonation.
The Petrologist’s Guide to the Galaxy: A method for modeling terrestrial exoplanets using the MELTS algorithm
(2015-09-17) Hull, Scott; Panero, Wendy
Recent technological advances in exoplanet detection have led to planetary findings on an unprecedented scale and opened the doors to a new area of geophysical inquiry. This inquiry includes both the hunt for Earth-like exoplanets and how planetary chemistry and physical properties vary from star to star. We are currently restricted to considering little more than the planet’s density and the distance from its star, which gives us only a vague insight into these new questions. This study has produced a method for creating a more detailed model of exoplanets using thermodynamic phase-equilibrium computer code and stellar compositions as representatives for exoplanet chemistry. Our findings hold evidence for plate tectonics and implications for core mass percentages, deep water cycles, and the potential for life on these recently discovered worlds. The MELTS algorithm is a petrological modeling software package that is widely used for thermodynamic phase-equilibrium calculations. We tuned MELTS to model exoplanets by producing an Earth-based “bulk silicate planet” and basalt within the program, and then applied these models to various stellar chemistries representative of their average terrestrial exoplanet. Through this process we were also able to determine the core mass percentage of a given exoplanet. The HeFESTo code was then used to model calculate basalt and mantle density changes as a function of depth, which helps to determine the likelihood of basalt-eclogite transitions on a given exoplanet. Using our method, we were able to produce basalt-eclogite transition findings for a sample of six stellar systems. The resulting method from this study will be useful for scientists looking not only for the prevalence of geological activities such as plate tectonics throughout the universe, but also for those hunting for extraterrestrial life by offering a way to determine which stars may harbor Earth-like worlds.
Modeling and Simulation of Non-Isothermal Gas-Assisted Injection Molding For Non-Newtonian Fluids
(2015-09-17) Kolliopoulos, Panayiotis K.; Koelling, Kurt W.
Current gas-assisted injection molding simulations do not accurately predict coating thickness of the frozen layer created by the polymer melt in non-isothermal systems. This project will present a hybrid control-volume finite element/finite-difference method to obtain a numerical simulation of gas-assisted injection molding for non-isothermal systems. In previous studies, a number of simplifying assumptions were made in order to make the simulation model simpler, however, those assumptions contributed to a significant error in predicting the coating thickness. The previous models will be improved upon by taking into account the temperature gradient during the penetration and the effect of forced convection heat transfer. Additionally, this project proposes the set up and performance of experiments at low capillary numbers, so the simulation model will fit non-isothermal systems at both high and low capillary numbers. Therefore, the goal of this project is to develop a simulation model in MATLAB that will more effectively predict the coating thickness in non-isothermal systems at a large range of capillary numbers.
Building a Framework for Professional Commitment: Stories of Professional Growth in an Undergraduate Introduction to Pharmacy Course
(2015-09-17) Williams, Victoria; Hale, Ken
With admissions to PharmD programs becoming increasingly competitive, sophisticated pre-pharmacy preparation is becoming increasingly important. Admissions committees are now looking at measures beyond academic merit to assess potential for success within a PharmD program and the profession. Factors such as motivation to become a pharmacist and attitudes regarding patient-centered care are being evaluated in application reviews and interviews of candidates. Applicants to PharmD programs are expected to exhibit commitment to the profession before entering pharmacy school. Little research has been done to analyze how students develop this commitment. This study attempts to determine how an undergraduate introductory course helps pre-professional students develop an informed commitment to the pharmacy profession. Students enrolled in Pharmacy 4511H were interviewed at the beginning and end of the course, as well as observed during selected class sessions throughout the semester. Eleven questions were asked in the first interview. In the follow-up interview, the same eleven questions were asked as well as four additional questions. Methods to enhance the credibility of this naturalistic research include prolonged engagement and persistent observation, negative case analyses, triangulation, progressive subjectivity, and member-checks. Coding and analysis of the interview transcripts shows that, with one exception, every student in the course solidified or increased their commitment to the profession. Students’ vocabulary when discussing pharmacy became more sophisticated as a result of taking this course. In general, students developed a more focused passion for the profession and were able to make more informed decisions regarding their career aspirations than they were able to previously. These preliminary findings suggest that an introductory pre-professional course can positively influence students’ conceptualization of and commitment to their intended careers. In the interest of developing competitive professional school applicants, other health professional schools could benefit from offering an introductory undergraduate course to improve applicants’ commitment.
Associations between teachers’ personality, psychological well-being, and the quality of their cocaring relationships
(2015-09-17) Maras, Elly; Schoppe-Sullivan, Sarah; Lang, Sarah
Recent research has explored the conceptual similarities between coparenting relationships and parent-teacher, or cocaring relationships, in infant and toddler classrooms (Lang, 2015). Cocaring is defined as the relationship between a parent and his or her child’s early childhood educator. Due to the novelty of this cocaring concept, this study aims to fill the gaps by including an observational understanding of how cocaring dimensions are enacted in daily exchanges between parents and teachers. This study will also examine how anxiety, depression, and personality traits impact the quality of the cocaring relationship. Parents and teachers of approximately 30 infants and toddlers, between 6-36 months of age, will be videotaped during pick-up and/or drop-off times in their childcare center classroom. This sample comes from 7 full-time, licensed childcare centers in Central Ohio. Additionally, each participant will fill out several scales including the Cocaring Relationship Questionnaire (Lang et. al, 2014), the Center Epidemiologic Studies Depression Scale (Radloff, 1977), the Spielberg State-Trait Anxiety Scale (Marteau & Bekker, 1992), and the NEO – Five Factor Inventory -3, a measure of personality (Costa & Roberts, 2010). By analyzing self-report data and observing teachers’ cocaring interactions in the classroom setting, this study will further our understanding of predictors of cocaring relationship functioning, including anxiety, depression, and specific personality traits. The information gained from this study will prove to be valuable for furthering the field’s theoretical understanding of parent-teacher relationships for very young children, especially when it comes to the overall functioning of cocaring relationships. The observational component of this study can also serve as the foundation for future intervention strategies, bringing the field one step closer towards improving cocaring relationships, and ultimately, positively impacting the development of young children in childcare.
The Progression of the Development of Antibody pY26: Recognizing Phosphorylated Troponin I at the Tyrosine-26 Amino Acid Residue
(2015-09-17) Gualtieri, Nicholas; Salhi, Hussam; Biesiadecki, Brandon
Antibodies are used in the western blot technique to identify or quantify a specific protein in a sample. These antibodies cannot be synthesized in a laboratory and must be developed within an animal. It can take months for the antibody to fully mature, and the antibody must be periodically tested to document its progression. The antibody of interest in this study identifies phosphorylated troponin I (TnI) at the Tyrosine-26 (Tyr-26) amino acid residue. The antibody was tested by using four known samples: human phosphorylated TnI, human non-phosphorylated TnI, rat phosphorylated TnI, and rat non-phosphorylated TnI. The antibody was tested at five different time intervals: Pre-bleed, and bleeds 1-4.Theoretically, the antibody would be observed on the phosphorylated samples and would not be observed on the non-phosphorylated samples. As time progresses, the antibody should also become more specific (binding only to phosphorylated TnI), and more intense (binding to phosphorylated TnI more frequently). As each subsequent test bleed was used on the samples, the specificity and intensity of the antibody increased. Further work was done on the antibody in terms of determining what concentration it should be used at to create the most clear images. When used at a 1:60,000 antibody:TBS + 0.1% Tween ratio, the image of the blot is the most clear. With an effective antibody that identifies phosphorylated TnI Tyr-26, unknown samples can be tested for the phosphorylation. Trends between heart failure and phosphorylation of the residue can be established and ultimately treatments can be created depending on the effect of the phosphorylation.
Prolonged Circulation of Peptide Amphiphiles for Cancer Imaging
(2015-09-17) Manos, Aaron; Goldberger, Joshua
There has been an emerging interest in designing smart, self-assembling, biocompatible materials that can selectively undergo morphological transitions to accumulate at a disease site in response to specific stimuli. One such stimulus is the acidic extracellular pH (6.6-7.0) of tumor tissue. Developing a contrast agent that can self-assemble into a larger, more slowly diffusing entity only in an acidic extracellular pH would enable magnetic resonance imaging (MRI) across all cancers. However, in vivo studies have shown that peptide amphiphiles (PAs) are rapidly cleared by the kidneys and uptaken by the mononuclear phagocyte system. Here, we have characterized the self-assembly of PAs conjugated to polyethylene glycol (PEG) that transition from spherical micelles at the physiological pH 7.4 to cylindrical nanofibers under more acidic pHs. The presence of PEG reduces the ζ-potential of the aggregates and increases the hydrodynamic radius, while increasing micelle formation propensity. The mixing of PEGylated PAs with (DO3A:Gd)-tagged PAs with stronger β-sheet forming region PAs allows for fine-tuning the pH trigger of self-assembly. These findings allow for prolonged-circulation time PA vehicles that transition from spherical micelle to cylindrical nanofiber in simulated serum which could lead to the development of the first pan-cancer MRI contrast agent.
How individual variation in activity influences the transmission of novel information
(2015-09-17) Troyer, Emily; Hamilton, Ian; Hoskins, Elizabeth
Novel information, such as the location of a food source, can be transmitted throughout a group via social learning, as opposed to direct sampling of the environment. Other information transmission models via social learning have not accounted for the fact that individuals will vary which may influence the rate at which information is transmitted throughout a group. Individuals may vary on personality traits, such as exploration, or the propensity to move around in their environment. The purpose of our model was to determine if individual variation in movement propensity, or activity level, influenced how quickly a novel piece of information was obtained by the entire group. We examined the propensity of an individual to move about its environment and how that influenced the rate of information transfer, compared to a model in which all the individuals were identical. We used an agent based model, in which agents, or individuals, moved around in an artificial environment and interacted with others in their group. We varied the probability each individual would move in a single time step to see how that influenced the speed at which novel information was transferred throughout the group. Results show that the propensity for movement does influence the transmission of social information. In a group of individuals that starts out with one individual in the novel state having a higher probability of movement, the entire group will obtain the novel information faster than if the starting individual in the novel state had a lower probability of movement.
Do Dogs Use Their Noses? Investigating Olfactory Perception in the Domestic Dog
(2015-09-17) Wilson, Sally; Yocom, Anna M.
The nasal tissue lining the domestic dogs’ (Canis familiaris) nasal cavity can have over 200 million sensory receptor sites all dedicated to receiving smell molecules to be processed in the brain’s olfactory bulb. But how dedicated are dogs to their extraordinary olfactory abilities? It has generally been assumed that dogs depend more on olfaction than vision and audition to investigate, problem solve, and overall perceive the world. However recent research has shown evidence that contradicts this assumption (Horowitz 2013), making it unclear under what conditions dogs actually utilize olfaction. The goal of the present research is to further investigate the question of how much and when dogs utilize olfaction. It was assessed whether shelter dogs would investigate and choose greater over smaller quantities of food through olfaction alone, if provided with a short investigation period to smell two closed containers with differing amounts of food (1:5). The preliminary results of the present research indicate that dogs were not successful at choosing greater over smaller quantities of food through olfaction alone, choosing the container with more food at only chance levels (binomial test, p > 0.05). Perhaps, due to domestication and their reliance on human communication, dogs may need training in order to use olfaction for problem solving. Likewise it may be found that only certain dog breeds, ages, or temperaments have this ability. Future analysis will examine initial investigation time of the food sources, as well as possible age, breed, and stress effects on olfactory ability. Results of this research will contribute to our currently limited understanding of olfaction, and give clearer insight into how dogs perceive and learn about the world, that could extend into developing more efficient training methods for service dogs.
Identifying an animal model to study the extracellular role of the bacterial toxin listeriolysin O
(2015-09-17) Yan, Shirui; Seveau, Stephanie
Listeriolysin O (LLO) is a cholesterol- dependent cytolysin (CDC) secreted by the foodborne, facultative intracellular pathogen Listeria monocytogenes. This toxin is released in the extracellular and intracellular environments, from where it binds to cholesterol on host cell membranes to form pores, facilitating disease development. Among the numerous members of the CDC family, LLO displays unique properties, such as temperature and pH sensitivity. At neutral pH and temperatures above 30°C, LLO undergoes denaturation. The kinetic of LLO inactivation at 37°C (PH 7.4) has not been established. Additionally, a recent study proposed that in comparison to human serum, murine serum highly inactivates another CDC family member, pneumolysin (PLY) produced by the bacterial pathogen Streptococcus pneumoniae. If this toxin-inhibitory property of murine serum also applies to LLO, this would imply that the murine model for L. monocytogenes infection is not appropriate to study the extracellular functions of LLO. The first goal of my work is to establish the kinetic curve model for different concentrations of LLO at 37°C and neutral pH. The second goal is to determine the relative inhibitory activity of sera obtained from various animal species in comparison to human sera in order to establish which animal models would be best to study LLO extracellular activities.
Liver inflammation exacerbates intraspinal tissue loss after spinal cord injury
(2015-09-17) Alfredo, Anthony N.; Sauerbeck, Andrew D.; Goodus, Matthew; Bruno, Richard S.; McTigue, Dana M.; McTigue, Dana M.
Spinal cord injury (SCI) is a devastating condition that impedes a patient’s motor and sensory function as well as physiological well-being. Epidemiologic research has shown that 10 to 40 people per million in the developed world are affected by SCI. Because the spinal cord innervates all the organs of the body, this terrible injury causes detrimental impairments of the peripheral organs and their regulation. Recent studies have established that the liver is a primary organ to immunologically respond to CNS injury. Prior work from our lab showed that immune system cells called Kupffer Cells (KCs), which are macrophages of the liver, initiate a prolonged pro-inflammatory response after SCI. Some reports in the literature suggest that liver inflammation may exacerbate lesion pathology in the spinal cord. However this has not been directly tested. Our objective for this study is to do a “gain of function” experiment to determine if inducing liver inflammation prior to SCI causes increased spinal inflammation and functional deficits. To cause liver inflammation, a new model needed to be established in the lab. Literature has shown that bile duct ligation (BDL) causes hepatic inflammation. Thus, BDL surgery was performed on Sprague-Dawley rats prior to sacrificing on day 1, 3, or 5 post-BDL. Rats were sacrificed by intracardiac perfusion and tissue was prepared for histological and molecular analysis. RT-PCR for BDL acute time course studies revealed a significant increase in pro-inflammatory cytokines TNF-α, IL-1β, and CD11b at 5 d post-BDL. To test this effect in SCI, another cohort of animals received BDL and 5d later received SCI. At 23 days post-injury, immunohistochemistry revealed that BDL animals had less spared tissue inside the spinal cord to controls. These results are concordant with our hypothesis and pave the way for future inquiry and therapeutically targeting the liver following injury.
Strategic Trade Theory in the Brazil-Canada WTO Dispute
(2015-09-17) Giblin, Peter; Sheldon, Ian
The market for regional jets is an excellent example of imperfect competition as only two firms, Canada’s Bombardier and Embraer of Brazil, compete for market share. In a market with non-cooperative rivalries and imperfect competition, there is an incentive for governments to subsidize the domestic firm and thus increase its profits at the expense of the foreign firm. In the strategic rivalry between Bombardier and Embraer the stakes were so high that both governments filed complaints at the WTO. Although there have been a number of strategic trade studies conducted on competition in the civil aircraft market, no studies have simulated the messy trade war between Canada and Brazil during the 1990s. The purpose of this study is to prove that the subsidy programs run by Brazil and Canada were jointly suboptimal and that the resolution of the dispute via the WTO had positive terms of trade benefits for each country. To evaluate the impact of Embraer’s entrance followed by the reduction of subsidies per the WTO mandated decisions, a calibrated model based off those developed by Baldwin and Krugman (1988) and Baldwin and Flam (1989) will be employed. As this project is still a work in progress the results of the simulations cannot be commented on. However, based off the results of the studies mentioned above, I expect to show a decrease in prices upon Embraer’s subsidized entrance into the market (and thus a terms of trade loss) and an increase in prices after the WTO ordered both sides to reduce their subsidy programs. These results will hopefully simulate the terms of trade losses of the jointly suboptimal subsidy. Through this study I hope to further highlight the overall negative impact subsidies can have on a country’s trade relations and terms of trade.
Pseudomonas aeruginosa Short-Range Signaling Protein Influence On Biofilm Phenotypic Expression
(2015-09-17) Mack, Lydia; Stoodley, Paul
Bacterial biofilms are communities of bacteria which grow on various surfaces. They are composed of the bacteria themselves and an extracellular polymeric slime (EPS) matrix which they encase themselves within. Biofilms can be found in any environment where there is persistent water, such as oceans, pipes, and the human body. Biofilms are formed when free-floating, planktonic bacteria attach to a surface and grow. Cells in a biofilm use communication via cell signaling bacteria to coordinate the behavior of the whole biofilm population for a diverse array of functions, including expression of virulence factors, proliferation and dispersal. In cell signaling, diffusible chemicals are released by individual bacteria which can be “sensed” by others in the biofilm. A short-range cell signaling protein in Myxococcus was discovered to be responsible for social motility in biofilms. We have identified a single potential protein homolog in Pseudomonas aeruginosa, PA4079, for which we are testing to determine social motility differences between a wild-type strain of P. aeruginosa versus a strain with a knockout of the PA4079 gene. Biofilms of both a wild-type strain with green fluorescent protein (GFP) and a PA4079 transposon knockout strain with GFP are grown under various media and temperature conditions. Images have been collected to compare phenotypic differences among the biofilms. Moving forward we will be using time-lapse photography to determine if dispersal rates and motility are affected by this protein. We will also be utilizing a flow cell setup to manipulate biofilms under shear stress. We believe the PA4079 gene and homologs may be responsible for dispersal from pathogenic biofilms and could represent a possible target for treating problematic biofilm infections. With the information provided from this research, we will be able to better understand social motility and cell-signaling of Pseudomonas aeruginosa. Our results could bring forth new ways to treat and prevent pathogenic biofilms within orthopedic environments (i.e implants, reparative surgeries) as well as natural environments.

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