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2017

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Increased Striatal Vulnerability To 3-Nitropropionic Acid In Male, But Not Female, Mice Lacking Interleukin-1r1, Matthew Frederick Allen Dec 2017

Increased Striatal Vulnerability To 3-Nitropropionic Acid In Male, But Not Female, Mice Lacking Interleukin-1r1, Matthew Frederick Allen

Theses - ALL

Interleukin-1β (IL-1β), classically considered as a pro-inflammatory cytokine, has proven essential to cellular defense in nearly all tissues (Kaur et al., 2014, Ren and Torres, 2009). In brain, studies suggest that IL-1β has pleiotrophic effects. It acts as a neuromodulator, has been implicated in the pathogenic processes associated with a number of CNS diseases, but has also been shown to provide protection to the injured CNS. With respect to the latter, IL-1β signalling appears to mitigate pathology and motor symptoms in a mouse model of Huntington’s disease (HD), a progressive neurodegenerative condition that targets the striatum. Specifically, HD mice bred …


International Differences In Support For Human Rights, Sam Mcfarland Phd Dec 2017

International Differences In Support For Human Rights, Sam Mcfarland Phd

Societies Without Borders

International differences in support for human rights are reviewed. The first of two sections reviews variations in the strength of ratification of UN human rights treaties, followed by an examination of the commonalities and relative strengths among the five regional human rights systems. This review indicates that internationally the strongest human rights support is found in Europe and the Americas, with weaker support in Africa, followed by still weaker support in the Arab Union and Southeast Asia. The second section reviews variations in responses to public opinion polls on a number of civil and economic rights. A strong coherence in …


Rainbows For Rights: The Role Of Lgbt Activism In Gay Rights Promotion, Victor Asal Phd, Amanda Murdie Phd, Udi Sommer Phd Dec 2017

Rainbows For Rights: The Role Of Lgbt Activism In Gay Rights Promotion, Victor Asal Phd, Amanda Murdie Phd, Udi Sommer Phd

Societies Without Borders

Are advocacy efforts successful in improving the de jure rights of sexual minorities? In this paper, we argue that the lesbian, gay, bisexual, and transgender (LGBT) rights NGO movement has been a powerful force in the struggle against sexual discrimination. However, the work of LGBT organizations is much harder in areas of the world where pre-existing public attitudes are not supportive of the rights in question. By focusing on the issue of sexual minority rights, we are able to see how underlying public attitude divergence on a human rights issue can influence advocacy success. We test the implications of our …


Who Says Human Rights Are Not Respected? Assessing Local And Third Party Ratings, Rob Clark Phd Dec 2017

Who Says Human Rights Are Not Respected? Assessing Local And Third Party Ratings, Rob Clark Phd

Societies Without Borders

Country ratings of human rights conditions are now quite popular in macro comparative research. However, little is known as to whether (or to what extent) these scores correspond with mass sentiment in each country. Do local ratings issued by the public correspond with third party ratings, such as those produced by the Cingranelli-Richards index (CIRI), the Political Terror Scale (PTS), and Freedom House (FH)? In this study, I address this question, drawing from the most recent wave of the World Values Survey (2010 – 2014), in which respondents from 59 countries are asked to assess the level of respect for …


Sexual Assault In Universities, Vanessa A. Gebka Dec 2017

Sexual Assault In Universities, Vanessa A. Gebka

Honors Capstones

In this study, the author investigates how and why rape culture continues to exist in our society today. Certain concepts such as gender roles, college experience, acquaintance rape, and victim blaming are discussed in order to elaborate on this ideology. Furthermore, the author looks at how rape culture effects outcomes and survivors of sexual assault, specifically within universities, and how institutions handle such cases. Using surveys and research, it is clear that victims of sexual assault are not being supported and more needs to be done to help them. The author argues that because college environments and institutions tolerate sexual …


Electromyography Exposes Heterogeneity In Muscle Co-Contraction Following Stroke, Caitlin L. Banks, Helen J. Huang, Virginia L. Little, Carolynn Patten Dec 2017

Electromyography Exposes Heterogeneity In Muscle Co-Contraction Following Stroke, Caitlin L. Banks, Helen J. Huang, Virginia L. Little, Carolynn Patten

PT Faculty Publications

Walking after stroke is often described as requiring excessive muscle co-contraction, yet, evidence that co-contraction is a ubiquitous motor control strategy for this population remains inconclusive. Co-contraction, the simultaneous activation of agonist and antagonist muscles, can be assessed with electromyography (EMG) but is often described qualitatively. Here, our goal is to determine if co-contraction is associated with gait impairments following stroke. Fifteen individuals with chronic stroke and nine healthy controls walked on an instrumented treadmill at self-selected speed. Surface EMGs were collected from the medial gastrocnemius (MG), soleus (SOL), and tibialis anterior (TA) of each leg. EMG envelope amplitudes were …


Perchlorate-Coupled Carbon Monoxide (Co) Oxidation: Evidence For A Plausible Microbe-Mediated Reaction In Martian Brines, Marisa R. Myers, Gary M. King Dec 2017

Perchlorate-Coupled Carbon Monoxide (Co) Oxidation: Evidence For A Plausible Microbe-Mediated Reaction In Martian Brines, Marisa R. Myers, Gary M. King

Faculty Publications

© 2017 Myers and King. The presence of hydrated salts on Mars indicates that some regions of its surface might be habitable if suitable metabolizable substrates are available. However, several lines of evidence have shown that Mars' regolith contains only trace levels of the organic matter needed to support heterotrophic microbes. Due to the scarcity of organic carbon, carbon monoxide (CO) at a concentration of about 700 parts per million (about 0.4 Pa) might be the single most abundant readily available substrate that could support near-surface bacterial activity. Although a variety of electron acceptors can be coupled to CO oxidation, …


Ability Of Functional Performance Tests To Identify Individuals With Chronic Ankle Instability: A Systematic Review With Meta-Analysis, Adam B. Rosen, Alan R. Needle, Jupil Ko Dec 2017

Ability Of Functional Performance Tests To Identify Individuals With Chronic Ankle Instability: A Systematic Review With Meta-Analysis, Adam B. Rosen, Alan R. Needle, Jupil Ko

Health and Kinesiology Faculty Publications

Objective:

The purpose of this systematic review with meta-analysis was to determine the effectiveness of functional performance tests (FPTs) in differentiating between individuals with chronic ankle instability (CAI) and healthy controls.

Data Sources:

The National Library of Medicine Catalog (PubMed), the Cumulative Index for Nursing and Allied Health Literature (CINAHL), and the SPORTDiscus, from inception to June 2017 were searched. Search terms consisted of: “Functional Performance Test*” OR “Dynamic Balance Test*” OR “Postural Stability Test*” OR “Star Excursion Balance Test*” OR “Hop Test*” AND “Ankle Instability” OR “Ankle Sprain.” Included articles assessed differences in FPTs in patients with CAI compared …


Concise Review: Translating Regenerative Biology Into Clinically Relevant Therapies: Are We On The Right Path?, Jennifer Simkin, Ashley W. Seifert Dec 2017

Concise Review: Translating Regenerative Biology Into Clinically Relevant Therapies: Are We On The Right Path?, Jennifer Simkin, Ashley W. Seifert

Biology Faculty Publications

Despite approaches in regenerative medicine using stem cells, bio-engineered scaffolds, and targeted drug delivery to enhance human tissue repair, clinicians remain unable to regenerate large-scale, multi-tissue defects in situ. The study of regenerative biology using mammalian models of complex tissue regeneration offers an opportunity to discover key factors that stimulate a regenerative rather than fibrotic response to injury. For example, although primates and rodents can regenerate their distal digit tips, they heal more proximal amputations with scar tissue. Rabbits and African spiny mice re-grow tissue to fill large musculoskeletal defects through their ear pinna, while other mammals fail to regenerate …


Father Involvement Among Asian-Indian Immigrants In The United States: Actor-Partner Interdependence Model, Dimple P. Vadgama Dec 2017

Father Involvement Among Asian-Indian Immigrants In The United States: Actor-Partner Interdependence Model, Dimple P. Vadgama

Dissertations - ALL

Parenting is codependent and nested within a familial and cultural structure. While parenting research consistently demonstrates more maternal involvement with children, often fathers’ involvement gets little or no attention. One of the major limitations of fathering research is single source data, often comprised of only mothers’ reports of fathers’ involvement. The purpose of this study was to address this gap by examining the nested nature and interdependence of immigrant parents’ marital adjustment, parenting self-efficacy, and beliefs about parental role and, fathers’ involvement. Actor-partner interdependence model (APIM) was applied to examine the actor (intrapersonal or spillover) and partner (interpersonal or crossover) …


Including Pork In The Mediterranean Diet For An Australian Population: Protocol For Arandomised Controlled Trial Assessing Cardiovascular Risk And Cognitive Function, Alexandra T. Wade, Courtney R. Davis, Kathryn A. Dyer, Jonathan M. Hodgson, Richard Woodman, Hannah A. Keage, Karen J. Murphy Dec 2017

Including Pork In The Mediterranean Diet For An Australian Population: Protocol For Arandomised Controlled Trial Assessing Cardiovascular Risk And Cognitive Function, Alexandra T. Wade, Courtney R. Davis, Kathryn A. Dyer, Jonathan M. Hodgson, Richard Woodman, Hannah A. Keage, Karen J. Murphy

Research outputs 2014 to 2021

Background

The Mediterranean diet is characterised by the high consumption of extra virgin olive oil, fruits, vegetables, grains, legumes and nuts; moderate consumption of fish, poultry, eggs and dairy; and low consumption of red meat and sweets. Cross sectional, longitudinal and intervention studies indicate that a Mediterranean diet may be effective for the prevention of cardiovascular disease and dementia. However, previous research suggests that an Australian population may find red meat restrictions difficult, which could affect long term sustainability of the diet.

Methods

This paper outlines the protocol for a randomised controlled trial that will assess the cardiovascular and cognitive …


Facilitating Social Support Systems For Adults In Assisted Living Communities, Kathryn Marie Detwiler Dec 2017

Facilitating Social Support Systems For Adults In Assisted Living Communities, Kathryn Marie Detwiler

Theses - ALL

This thesis project seeks to unpack how older adults living in assisted living facilities

maintain and deepen their social connections. According to established research, social support systems and active lifestyles are major factors in improving quality of life. By sitting down with residents in the assisted living division of Menorah Park in

Syracuse, and conducting a series of research activities, a better understanding of how older adults live in assisted living facilities.

One potential design solution currently being explored to keep older adults socially engaged could be the design of a social hub terminal that encourages residents to congregate daily …


State V. Coleman Appellant's Reply Brief Dckt. 45032 Dec 2017

State V. Coleman Appellant's Reply Brief Dckt. 45032

Idaho Supreme Court Records & Briefs, All

No abstract provided.


Cdc Grand Rounds: National Amyotrophic Lateral Sclerosis (Als) Registry Impact, Challenges, And Future Directions, Paul Mehta, D. Kevin Horton, Edward J. Kasarskis, Ed Tessaro, M. Shira Eisenberg, Susan Laird, John Iskander Dec 2017

Cdc Grand Rounds: National Amyotrophic Lateral Sclerosis (Als) Registry Impact, Challenges, And Future Directions, Paul Mehta, D. Kevin Horton, Edward J. Kasarskis, Ed Tessaro, M. Shira Eisenberg, Susan Laird, John Iskander

Neurology Faculty Publications

Amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig’s disease, is a rapidly progressive fatal neurologic disease. Currently, there is no cure for ALS and the available treatments only extend life by an average of a few months. The majority of ALS patients die within 2–5 years of diagnosis, though survival time varies depending on disease progression (1,2). For approximately 10% of patients, ALS is familial, meaning it and has a genetic component; the remaining 90% have sporadic ALS, where etiology is unknown, but might be linked to environmental factors such as chemical exposures (e.g., heavy …


Gas Phase Oxidation Of Levulinic Acid For The Production Of Maleic Anhydride Over Supported Vanadium Oxide Catalysts, Anargyros Chatzidimitriou Dec 2017

Gas Phase Oxidation Of Levulinic Acid For The Production Of Maleic Anhydride Over Supported Vanadium Oxide Catalysts, Anargyros Chatzidimitriou

Dissertations - ALL

With continued depletion of fossil carbon, there is a need to utilize renewable sources of energy and consumer end products. In this context, we examine the aerobic oxidation of levulinic acid, a bio-based platform chemical derived from lignocellulosic biomass, to produce maleic anhydride, a valuable commodity chemical. This process is carried out over supported vanadium oxide catalysts. Yields as high as 71% of the theoretical maximum were achieved at 573 K over a vanadium oxide catalyst supported on SiO2. The exact mechanism underlying this transformation is complex, but our results suggest that maleic anhydride forms by the oxidative cleavage of …


Oxygen Transport Membrane Reactors For Oxy-Fuel Combustion And Carbon Capture Purposes, Ryan Falkenstein-Smith Dec 2017

Oxygen Transport Membrane Reactors For Oxy-Fuel Combustion And Carbon Capture Purposes, Ryan Falkenstein-Smith

Dissertations - ALL

This thesis investigates oxygen transport membrane reactors (OTMs) for the application of oxy-fuel combustion. This is done by evaluating the material properties and oxygen permeability of different OTM compositions subjected to a variety of operating conditions. The scope of this work consists of three components: (1) evaluate the oxygen permeation capabilities of perovskite-type materials for the application of oxy-fuel combustion; (2) determine the effects of dual-phase membrane compositions on the oxygen permeation performance and membrane characteristics; and (3) develop a new method for estimating the oxygen permeation performance of OTMs utilized for the application of oxy-fuel combustion.

SrSc0.1Co0.9O3-δ (SSC) is …


Wifely Figures: Gender, Marriage, And Biblical Typology In Early Modern England, Melissa Welshans Dec 2017

Wifely Figures: Gender, Marriage, And Biblical Typology In Early Modern England, Melissa Welshans

Dissertations - ALL

This dissertation illuminates how the hermeneutic of biblical typology influenced the conception of the female life cycle in early modern English literature, especially the social roles of maid, wife, and widow. Reading texts from a variety of genres and by both male and female authors, this dissertation argues that a typological understanding of marriage gave additional, spiritual import to those social roles, thus further upholding ideologies that defined women by their proximity to marriage. However, this dissertation also demonstrates how a typological understanding of marriage and the female life cycle could also be used to critique gender norms. After providing …


Investigating The Interaction Of A Supersonic Single Expansion Ramp Nozzle And Sonic Wall Jet, Matthew Berry Dec 2017

Investigating The Interaction Of A Supersonic Single Expansion Ramp Nozzle And Sonic Wall Jet, Matthew Berry

Dissertations - ALL

For nearly 80 years, the jet engine has set the pace for aviation technology around the world. Complexity of design has compounded upon each iteration of nozzle development, while the rate of fundamental fluids knowledge struggles to keep up. The increase in velocities associated with supersonic jets, have exacerbated the need for flow physics research. Supersonic flight remains the standard for military aircraft and is being rediscovered for commercial use. With the addition of multiple streams, complex nozzle geometries, and airframe integration in modern aircraft, the flow physics rapidly become more difficult. As performance capabilities increase, so do the noise …


Ensemble Methods For Anomaly Detection, Zhiruo Zhao Dec 2017

Ensemble Methods For Anomaly Detection, Zhiruo Zhao

Dissertations - ALL

Anomaly detection has many applications in numerous areas such as intrusion detection, fraud detection, and medical diagnosis. Most current techniques are specialized for detecting one type of anomaly, and work well on specific domains and when the data satisfies specific assumptions.

We address this problem, proposing ensemble anomaly detection techniques that perform well in many applications, with four major contributions: using bootstrapping to better detect anomalies on multiple subsamples, sequential application of diverse detection

algorithms, a novel adaptive sampling and learning algorithm in which the anomalies are iteratively examined, and improving the random forest algorithms for detecting anomalies in streaming …


Design, Synthesis And Study Of Thermomechanically Active Polymer Networks Based On Latent Crosslinking Of Semicrystalline Polymers, Wenbin Kuang Dec 2017

Design, Synthesis And Study Of Thermomechanically Active Polymer Networks Based On Latent Crosslinking Of Semicrystalline Polymers, Wenbin Kuang

Dissertations - ALL

Demand has arisen rapidly for smart materials in the world of the need to develop and understand new functional products like plastics, rubber, adhesives, fibers, and coatings. Such products are essentially composed of polymers, large molecules of high molecular weight with homogeneous or various repeating units, which researchers term “macromolecules” that engender specific structural, morphological, and physical and mechanical properties. Those polymers with the capacity to change their configuration in accordance with environmental alteration are specifically referred to as shape memory polymers (SMPs), attracting much interest of study both academically and industrially. Herein, this dissertation aims at design, fabrication, and …


Adsorption Of Iodine And Water On Silver-Exchanged Mordenite, Yue Nan Dec 2017

Adsorption Of Iodine And Water On Silver-Exchanged Mordenite, Yue Nan

Dissertations - ALL

The reprocessing of used nuclear fuel to recover the fissile materials generates off gases including radioactive nuclides namely 3H (tritiated water, H3HO), 129I, 85Kr, 135Xe, and 14C. Due to its high quantity in off-gas streams and long half-life (1.59 million years), 129I removal from the off-gas streams is a significant objective of off-gas treatment.

129I retention by solid adsorbents was recognized a better strategy in comparison to liquid scrubbers due to the simplicity of system design and low cost. Among the studied adsorbents, reduced silver-exchanged mordenite (Ag0Z) was widely recognized as the state-of-art adsorbent for iodine removal. It has been …


Vortex Detection And Tracking In Massively Separated And Turbulent Flows, Yangzi Huang Dec 2017

Vortex Detection And Tracking In Massively Separated And Turbulent Flows, Yangzi Huang

Dissertations - ALL

The vortex produced at the leading edge of the wing, known as the leading edge vortex (LEV), plays an important role in enhancing or destroying aerodynamic force, especially lift, upon its formation or shedding during the flapping flight of birds and insects. In this thesis, we integrate multiple new and traditional vortex identification approaches to visualize and track the LEV dynamics during its shedding process. The study is carried out using a 2D simulation of a flat plate undergoing a 45 degree pitch-up maneuver. The Eulerian 𝛤1 function and 𝑄 criterion are used along with the Lagrangian coherent structures (LCS) …


Catalytic Synthesis Of Biodiesel Fuel Under Sub/Supercritical Conditions: Kinetics And Phase Behavior, Jiuxu Liu Dec 2017

Catalytic Synthesis Of Biodiesel Fuel Under Sub/Supercritical Conditions: Kinetics And Phase Behavior, Jiuxu Liu

Dissertations - ALL

In this thesis, transesterification of triglycerides and esterification of free fatty acids were executed under subcritical and supercritical alcohol conditions, and discussed in Chapter 2-5. The project was initiated by studying the phase behavior and kinetics of transesterification reactions under severe reaction conditions (T: 300-400 oC, P=200 bar), since those conditions were suggested and commonly used in the literature. At these conditions, triglycerides reacted with alcohol within minutes, and the oil-alcohol mixture formed a homogeneous phase which minimized the boundary mass transfer resistance. The composition change of the reaction mixture made the critical point of the system approach supercritical region …


Design Of Tribologically Enhanced Polymeric Materials For Biomedical Applications, Allen Osaheni Dec 2017

Design Of Tribologically Enhanced Polymeric Materials For Biomedical Applications, Allen Osaheni

Dissertations - ALL

Anytime two surfaces are in normal contact, accompanied by tangential motion, there is potential for deterioration of one or both surfaces. Gradual wear, or the removal of surface material, is typically an undesirable event. Therefore, the need for lubrication arises to minimize the amount of shear stress that develops between opposing surfaces. This reduction in shear stress is characterized by the coefficient of friction (COF). Friction is one of the primary subjects of interest in tribology, the science of the friction and wear of articulating surfaces.

A number of fascinating tribological systems can be found in nature. One example which …


Fossils, Heritage And Conservation: Managing Demands On A Precious Resource, Kn Page Dec 2017

Fossils, Heritage And Conservation: Managing Demands On A Precious Resource, Kn Page

School of Geography, Earth and Environmental Sciences

This book is an essential resource for geoscientists, park and geopark managers, tourism and regional planning managers, as well as university students interested in geoheritage, geosites, geomorphosites, geoconservation, and geotourism.


Rectangular Waveguide Filled With Uniaxial Medium And Negative Resistance Enhanced Composite Right/Left-Handed Transmission Line, Kepei Sun Dec 2017

Rectangular Waveguide Filled With Uniaxial Medium And Negative Resistance Enhanced Composite Right/Left-Handed Transmission Line, Kepei Sun

Dissertations - ALL

Two wave-guiding problems are treated in this work. The first part addresses the problem of a rectangular waveguide filled with a uniaxially anisotropic or uniaxial medium. Different orientations of the optic axis of the uniaxial medium are considered and the wave transmission and modal behaviors are investigated. When the optic axis is aligned with one of the coordinate axes, i. e., x, y, or z axis, the method of wave decomposition with respect to the optic axis orientation is proposed and the complete analytic solutions are presented and compared with conventional transverse-to-z solutions. When the optic axis is tilted but …


The Effects Of Gross-Motor Fluency Training On Physical Activity Levels In Young Children, Allison Jayne Womack Dec 2017

The Effects Of Gross-Motor Fluency Training On Physical Activity Levels In Young Children, Allison Jayne Womack

Dissertations - ALL

Engaging in regular physical activity is one of the most important factors related to good health. Encouraging and promoting physical activity in young children aids in preventing overweight and obesity, promoting health, preventing disease, and supporting bone and overall growth development. However, physical activity levels in young children are low, and efficient and effective interventions to increase physical activity in young children are unclear. One creative method to increase physical activity in young children is gross-motor fluency training. A multielement single-case experimental design was employed to assess the effects of fluency training in six gross-motor skills on children’s levels of …


Development And Evaluation Of A Connective Tissue Phantom Model For Subsurface Visualization Of Cancers Requiring Wide Local Excision, Kimberly S. Samkoe, Brent D. Bates, Niki N. Tselepidakis, Alisha V. Dsouza, Jason R. Gunn, Dipak B. Ramkumar, Keith D. Paulsen, Brian W. Pogue, Eric R. Henderson Dec 2017

Development And Evaluation Of A Connective Tissue Phantom Model For Subsurface Visualization Of Cancers Requiring Wide Local Excision, Kimberly S. Samkoe, Brent D. Bates, Niki N. Tselepidakis, Alisha V. Dsouza, Jason R. Gunn, Dipak B. Ramkumar, Keith D. Paulsen, Brian W. Pogue, Eric R. Henderson

Dartmouth Scholarship

Wide local excision (WLE) of tumors with negative margins remains a challenge because surgeons cannot directly visualize the mass. Fluorescence-guided surgery (FGS) may improve surgical accuracy; however, conventional methods with direct surface tumor visualization are not immediately applicable, and properties of tissues surrounding the cancer must be considered. We developed a phantom model for sarcoma resection with the near-infrared fluorophore IRDye 800CW and used it to iteratively define the properties of connective tissues that typically surround sarcoma tumors. We then tested the ability of a blinded surgeon to resect fluorescent tumor-simulating inclusions with ∼1-cm margins using predetermined target fluorescence intensities …


Treatment And Prevention Of Opioid Use Disorder: Challenges And Opportunities, Dennis Mccarty, Kelsey C. Priest, P. Todd Korthuis Dec 2017

Treatment And Prevention Of Opioid Use Disorder: Challenges And Opportunities, Dennis Mccarty, Kelsey C. Priest, P. Todd Korthuis

OHSU-PSU School of Public Health Faculty Publications and Presentations

Treatment for opioid use disorder in the United States evolved in response to changing federal policy and advances in science. Inpatient care began in 1935 with the US Public Health Service Hospitals in Lexington, Kentucky, and Fort Worth, Texas. Outpatient clinics emerged in the 1960s to provide aftercare. Research advances led to opioid agonist and opioid antagonist therapies. When patients complete opioid withdrawal, return to use is often rapid and frequently deadly. US and international authorities recommend opioid agonist therapy (i.e., methadone or buprenorphine). Opioid antagonist therapy (i.e., extended-release naltrexone) may also inhibit return to use. Prevention efforts emphasize public …


Structural Evidence Of A Major Conformational Change Triggered By Substrate Binding In Dape Enzymes: Impact On The Catalytic Mechanism, Boguslaw Nocek, Cory Reid, Anna Starus, Tahirah Heath, David Bienvenues, Jerzy Osipiuk, Robert Jedrzeczak, Andrzej Joachimiak, Daniel P. Becker Ph.D., Richard C. Holz Dec 2017

Structural Evidence Of A Major Conformational Change Triggered By Substrate Binding In Dape Enzymes: Impact On The Catalytic Mechanism, Boguslaw Nocek, Cory Reid, Anna Starus, Tahirah Heath, David Bienvenues, Jerzy Osipiuk, Robert Jedrzeczak, Andrzej Joachimiak, Daniel P. Becker Ph.D., Richard C. Holz

Chemistry: Faculty Publications and Other Works

The X-ray crystal structure of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase from Haemophilus influenzae (HiDapE) bound by the products of hydrolysis, succinic acid and l,l-DAP, was determined at 1.95 Å. Surprisingly, the structure bound to the products revealed that HiDapE undergoes a significant conformational change in which the catalytic domain rotates ∼50° and shifts ∼10.1 Å (as measured at the position of the Zn atoms) relative to the dimerization domain. This heretofore unobserved closed conformation revealed significant movements within the catalytic domain compared to that of wild-type HiDapE, which results in effectively closing off access to …