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Physiological Models Of Geobacter Sulfurreducens And Desulfobacter Postgatei To Understand Uranium Remediation In Subsurface Systems, Roberto Orellana Nov 2014

Physiological Models Of Geobacter Sulfurreducens And Desulfobacter Postgatei To Understand Uranium Remediation In Subsurface Systems, Roberto Orellana

Doctoral Dissertations

Geobacter species are often the predominant Fe(III)-reducing microorganisms in many sedimentary environments due to their capacity for extracellular electron transfer. This exceptional physiological capability allows them to couple acetate oxidation to uranium (U(VI)) reduction, that is one of the most significant interactions between radionuclides and microorganisms that naturally takes place in uranium-contaminated environments. Although this process has been proposed as a promising strategy for the in situ bioremediation of uranium-contaminated groundwater, little is known about the molecular mechanisms involved in U(VI) reduction and the interaction between Geobacter and other microbial species. In the first two research chapters, this dissertation aim …


Engineering Surface Functionality Of Nanoparticles For Biological Applications, Yi-Cheun Yeh Nov 2014

Engineering Surface Functionality Of Nanoparticles For Biological Applications, Yi-Cheun Yeh

Doctoral Dissertations

Engineering the surface functionality of nanomaterials is the key to investigate the interactions between nanomaterials and biomolecules for potent biological applications such as therapy, imaging and diagnostics. My research has been orientted to engineer both of the surface monolayers and core materials to fabricate surface-functionalized nanomaterials through the synergistic multidisciplinary approach that combine organic chemistry, materials science and biology. This thesis illustrates the design and synthesis of the surface-funcitonalized quantum dots (QDs) and gold nanoparticles (AuNPs) for the fundamental studies and practical applications. For QDs, A new class of cationic QDs with quaternary ammonium derivatives was synthesized to provide permanent …


Elucidating Cellular Signaling Pathways That Contribute To The Immunopathogenesis Of Aplastic Anemia, Christina M. Kuksin Nov 2014

Elucidating Cellular Signaling Pathways That Contribute To The Immunopathogenesis Of Aplastic Anemia, Christina M. Kuksin

Doctoral Dissertations

Aplastic Anemia is a rare immune mediated bone marrow failure disease that is mediated by autoreactive T cells that cause destruction to the stem, progenitor, and stromal cells in the bone marrow. Because little is known about the etiology of the disease, our lab has developed a major MHC mismatch GVHD model to examine cellular pathways in autoreactive T cells that contribute to disease. We examined three pathways that are important in T cell activation and differentiation and asked if they were important in the development of Aplastic Anemia. First, we were able to show that expression of active PKCθ …


Movements And Conservation Of The Migratory White-Eared Kob (Kobus Kob Leucotis) In South Sudan, Malik D. Marjan Nov 2014

Movements And Conservation Of The Migratory White-Eared Kob (Kobus Kob Leucotis) In South Sudan, Malik D. Marjan

Doctoral Dissertations

The annual movements of white-eared kob (Kobus kob leucotis), tiang (Damaliscus korrigum tiang), in eastern South Sudan was investigated to provided appropriate information for developing effective conservation actions for the migratory kob. Although kob is the focus of the study tiang has been included as the two migrations are ecologically linked and overlap at least in the wet season. During the 20 years of the civil war which ravaged South Sudan, the kob and tiang populations were thought to be severely hunted for food by both the combatants and local people to the extent that their …


Guanidinium-Rich Romp Polymers Drive Phase, Charge, And Curvature-Specific Interactions With Phospholipid Membranes, Michael T W Lis Nov 2014

Guanidinium-Rich Romp Polymers Drive Phase, Charge, And Curvature-Specific Interactions With Phospholipid Membranes, Michael T W Lis

Doctoral Dissertations

Protein transduction domains (PTDs) and their and their synthetic mimics are short sequences capable of unusually high uptake in cells. Several varieties of these molecules, including the arginine-rich Tat peptide from HIV, have been extensively used as vectors for protein, DNA, and siRNA delivery into cells. Despite the wide-ranging utility of PTDs and their mimics, their uptake mechanism is still under considerable debate. How the molecules are able to cross phospholipid membranes, and what structural components are necessary for optimal activity are poorly understood. This thesis explores how PTDMs interact with phospholipid membrane phase, anionic lipid content and negative Gaussian …


The Role Of Napping On Memory Consolidation In Preschool Children, Laura Kurdziel Nov 2014

The Role Of Napping On Memory Consolidation In Preschool Children, Laura Kurdziel

Doctoral Dissertations

Nocturnal sleep has been shown to benefit memory in adults and children. During the preschool age range (~3-5 years), the distribution of sleep across the 24-hour period changes dramatically. Children transition from biphasic sleep patterns (a nap in addition to overnight sleep) to a monophasic sleep pattern (only overnight sleep). In addition, early childhood is a time of neuronal plasticity and pronounced acquisition of new information. This dissertation sought to examine the relationship between daytime napping and memory consolidation in preschool-aged children during this transitional time. Children were taught either a declarative or an emotional task in the morning, and …


Impact Of Surface Active Minor Components On Physicochemical Properties Of Association Colloids And Lipid Oxidation In Bulk Oil, Ketinun Kittipongpittaya Nov 2014

Impact Of Surface Active Minor Components On Physicochemical Properties Of Association Colloids And Lipid Oxidation In Bulk Oil, Ketinun Kittipongpittaya

Doctoral Dissertations

Lipid oxidation is a great concern for food manufacturers and consumers as it negatively impacts not only food quality and nutritive values of food lipids, but also consumer health. Lipid oxidation in bulk oil is impacted by chemical factors, such as, prooxidants and antioxidants, and is also related to the existence of physical structures. Bulk oils contain a variety of surface active minor components which are able to form physical structures known as association colloids. These physical structures create oil-water interfaces which seem to be an important site where lipid oxidation occurs in bulk oil. Thus, this research focused on …


Nanoparticle Building Blocks For Functional Structures, Youngdo Jeong Nov 2014

Nanoparticle Building Blocks For Functional Structures, Youngdo Jeong

Doctoral Dissertations

A major goal in material science is achieving a desired function using structures fabricated with designed building blocks. Advanced synthetic and self-assembly techniques allow various nanomaterials to become promising building blocks, providing the control of the interaction between building blocks. The unique properties of nanomaterials can be transferred to structured systems. Among nanomaterials, inorganic nanoparticles such as gold nanoparticles (AuNPs), magnetic particles, and quantum dots (QDs) provide useful physical properties stemming from their inorganic core, large surface areas, and oriented surface functionalities. My research has focused on fabricating functional systems using gold nanoparticles (AuNPs), manipulating the interaction between AuNPs, bio-entities, …


Aggressive Signaling In New World Warblers, David Hof Nov 2014

Aggressive Signaling In New World Warblers, David Hof

Doctoral Dissertations

In many animal species, communication can enable individuals to resolve conflict without the high potential costs involved in direct fighting. During contests, animals may exchange information about their aggressive motivational state. A central question throughout the study of animal communication research has been whether animal signals convey reliable information, and this question has been particularly relevant to communication during conflicts where the evolutionary interests of competitors directly oppose. Deceptive signaling of aggressive motivation would be highly favored by natural selection because it could allow individuals to gain access to resources they might not gain through direct combat. However, selection should …


Factor Inhibiting Hif's (Fih) Structure Controls O2 Activation And Reactivity, John A. Hangasky Iii Nov 2014

Factor Inhibiting Hif's (Fih) Structure Controls O2 Activation And Reactivity, John A. Hangasky Iii

Doctoral Dissertations

Factor Inhibiting HIF (FIH) is a Fe(II)-αKG dependent oxygenase that acts as a cellular oxygen sensor in humans. FIH regulates the transcriptional activity of the hypoxia-inducible factor-1 (HIF-1a or HIF), a transcription factor responsible cellular O2 homeostasis. Hydroxylation of the target residue HIF-Asn803, found in the C-terminal transactivation domain (CTAD), inactivates HIF-dependent gene expression. Central to FIH’s function is the activation of O2 after CTAD binding. The mechanistic and structural features of FIH leading to tight coupling between CTAD binding and subsequent O2-activation and reactivity are key for efficient O2 sensing. Our mechanistic …


Understanding The Transcriptional Regulation Of Secondary Cell Wall Biosynthesis In The Model Grass Brachypodium Distachyon, Pubudu Handakumbura Nov 2014

Understanding The Transcriptional Regulation Of Secondary Cell Wall Biosynthesis In The Model Grass Brachypodium Distachyon, Pubudu Handakumbura

Doctoral Dissertations

Secondary cell wall synthesis occurs in specialized cell types following completion of cell enlargement. By virtue of mechanical strength provided by a wall thickened with cellulose, hemicelluloses, and lignin, these cells can function as water-conducting vessels and provide structural support. Several transcription factor families regulate genes encoding wall synthesis enzymes. Certain NAC and MYB proteins directly bind upstream of structural genes and other transcription factors. The most detailed model of this regulatory network is established predominantly for a eudicot, Arabidopsis thaliana. In grasses, both the patterning and the composition of secondary cell walls are distinct from that of eudicots. …


Integrated Modeling Of Land Use And Climate Change Impacts On Multiscale Ecosystems Of Central African Watersheds, Simon Nampindo Nov 2014

Integrated Modeling Of Land Use And Climate Change Impacts On Multiscale Ecosystems Of Central African Watersheds, Simon Nampindo

Doctoral Dissertations

Assessment and management of ecosystem services demands diverse knowledge of the system components. Land use change occurring mainly through deforestation, expansion of agriculture and unregulated extraction of natural resources are the greatest challenges of the Congo basin and yet is central to supporting over 100 million people. This study undertook to implement an integrated modeling of multiscale ecosystems of central African watersheds and model the impact of anthropogenic factors on elephant population in Greater Virunga landscape. The study was conducted at varied scales, regional, landscape, and community. Regional study included watershed analysis and hydrological assessment using remotely sensed data implemented …


The Identification And Characterization Of A Group Of Er Tpr-Containing Adapter Proteins, Johan C. Sunryd Nov 2014

The Identification And Characterization Of A Group Of Er Tpr-Containing Adapter Proteins, Johan C. Sunryd

Doctoral Dissertations

The endoplasmic reticulum (ER) is an organelle responsible for a variety of functions in all eukaryotic cells. Some of these functions are localized to specific regions in the ER, such as the ribosome-studded rough ER sheets or the ribosome-free smooth ER sheets. The smooth ER sheets have the ability to form ER tubules, which extend throughout the cell and make contact with other organelles. In order to accommodate these localized functional regions, a certain degree of heterogeneity and compartmentalization into sub-domains exists within the ER. Since the ER membrane and lumen are contiguous, the compartmentalization of the ER into sub-domain …


Dried Whole Plant Artemisia Annua As A Novel Antimalarial Therapy, Mostafa A. Elfawal Nov 2014

Dried Whole Plant Artemisia Annua As A Novel Antimalarial Therapy, Mostafa A. Elfawal

Doctoral Dissertations

Dried Whole plant Artemisia annua as a novel antimalarial therapy September 2014 Mostafa Ahmed Elfawal Ph.D., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Stephen M. Rich Malaria is one of the worst vector-borne parasitic diseases in the developing world. The World Health Organization (WHO) estimated that 215 million cases of malaria occurred, with >655,000 deaths; half the world’s population is at risk of contracting the disease. Drugs are primary weapons for reducing malaria in human populations. Successful drugs are highly efficacious and inexpensive to manufacture synthetically. However, emergence of resistant parasites has repeatedly curtailed the lifespan of each drug that …


Turning Up The Heat On The Little Things That Run The World: Evaluating The Impacts Of Climate Change On Ant Biodiversity In The Temperate Forest Communities Of The Northeastern United States, Israel Del Toro Nov 2014

Turning Up The Heat On The Little Things That Run The World: Evaluating The Impacts Of Climate Change On Ant Biodiversity In The Temperate Forest Communities Of The Northeastern United States, Israel Del Toro

Doctoral Dissertations

Climatic change threatens biodiversity worldwide. In the forests of the northeastern United States, climate change is expected to increase mean annual temperatures by up to 4.5˚C and change precipitation seasonality. These changes in climate are likely to have impacts on the biodiversity of the region. In order to better understand the impacts of climate change on biodiversity, I used ants, an indicator taxonomic group, to predict how ant communities and ant-mediated ecosystem processes change as the climate warms. In the first chapter of this dissertation, I review the major ecosystem processes and services mediated by ants using the Millennium Ecosystem …


Characterization Of Ca2+ Influx Pathway(S) During Mouse Oocyte Maturation, Banyoon Cheon Nov 2014

Characterization Of Ca2+ Influx Pathway(S) During Mouse Oocyte Maturation, Banyoon Cheon

Doctoral Dissertations

Ca2+ signaling induced at fertilization, also known as oscillations, is essential in mammalian eggs to initiate early embryonic development. The generation of the oscillations relies on optimization of Ca2+ toolkit components during oocyte maturation. In this dissertation, we intend to deepen our understanding of how this differentiation of the Ca2+ toolkit, especially those components associated with Ca2+ influx, is achieved during maturation, and how it contributes to the filling of the ER Ca2+ store during the maturation and fertilization. We first identified the expression and characterized the function of the components of the Store Operated …


Influence Of Lipoteichoic Acid On Listeria Monocytogenes Biofilm Formation And Cellular Stress, Imelda T. Brooks Nov 2014

Influence Of Lipoteichoic Acid On Listeria Monocytogenes Biofilm Formation And Cellular Stress, Imelda T. Brooks

Doctoral Dissertations

Lipoteichoic acid (LTA) is an important polymer on the surface of Gram-positive organisms, including the foodborne, biofilm-forming pathogen Listeria monocytogenes, and is connected to the cell membrane through a glycolipid backbone. Previous results have shown the importance of LTA in cell viability and biofilm formation. The purpose of this research is to further investigate the influence of LTA in L. monocytogenes biofilm formation and how the bacterium responds to environmental stress caused by antimicrobial exposures, and a combination of low temperature and high osmolarity. We created in frame deletion mutants along the operon lmo-2555-lmo2554-lmo2553, which have been shown …


Understanding Lipid Oxidation In Low-Moisture Food, Leann M. Barden Nov 2014

Understanding Lipid Oxidation In Low-Moisture Food, Leann M. Barden

Doctoral Dissertations

Low-moisture snacks account for much of the saturated fat in the diet, making them a key target for improving consumers’ health. However, it is not currently feasible to maintain the same shelf life when replacing saturated fats with unsaturated fats in these products. The first study characterized the microstructure of a low-moisture cracker model system and determined the impact of iron, chelators, and free fatty acids (FFA) on lipid oxidation kinetics. Confocal microscopy showed that lipids form a continuous layer surrounding the small and/or minimally gelatinized starch granules. Lipid-starch, lipid-air, and starch-lipid-protein interfaces all existed. Oxidation studies showed a large …


Landscape Predictors Of Current And Future Distribution Of Mountain Gorillas (Gorilla Beringei Beringei) In Bwindi Impenetrable National Park, Uganda, Dennis Babaasa Nov 2014

Landscape Predictors Of Current And Future Distribution Of Mountain Gorillas (Gorilla Beringei Beringei) In Bwindi Impenetrable National Park, Uganda, Dennis Babaasa

Doctoral Dissertations

Context: The impacts of ecological, anthropogenic and future climate change on the distribution of wild mountain gorillas (Gorilla beringei beringei) are of ongoing concern. Knowing the factors that determine gorilla habitat suitability now and in future is essential for conservation planning. The mountain gorilla is recognized by IUCN Red Data Book as critically endangered and a great tourist attraction. However, the factors that impact on their spatial use of Bwindi are poorly understood. Aims: I aimed at determining the major factors that determine gorilla distribution, predict the wild gorilla habitat suitability and establish the vulnerability index …


The Estradiol-Induced Transcriptome Of The Female Mouse Anteroventral Periventricular Nucleus: More Than Just A Kiss, Leah K. Aggison Nov 2014

The Estradiol-Induced Transcriptome Of The Female Mouse Anteroventral Periventricular Nucleus: More Than Just A Kiss, Leah K. Aggison

Doctoral Dissertations

Estradiol (E2) is critical in the reproductive mechanisms of mammals. In female rodents E2 acts through the neurons of the anteroventral periventricular nucleus (AVPV) to exert neuroendocrine control over ovulation, via synaptic activation of the gonadotropin releasing hormone (GnRH) neurons. The neurocircuitry of the AVPV is complex, receiving input from the suprachiasmatic nucleus and ventral premammillary nucleus and the as well as projecting to organum vasculosum of lamina terminalis and the arcuate. This suggests a broader role for the AVPV as a center of multisignal-integration in regards to ovulation. I used full genome expression microarrays to assess …


Susceptibility Of Escherichia Coli O157:H7, Salmonella Enterica Sp., And Listeria Monocytogenes To Antimicrobial Mixed Micelle Delivery Systems, Chanelle N. Adams Nov 2014

Susceptibility Of Escherichia Coli O157:H7, Salmonella Enterica Sp., And Listeria Monocytogenes To Antimicrobial Mixed Micelle Delivery Systems, Chanelle N. Adams

Doctoral Dissertations

Within the food industry, there is an ever increasing demand to improve the quality of food and ensure safety from pathogenic/spoilage microorganisms. Globalization of the food industry in the 1990’s, in conjunction with the worldwide shipment of food created a need for the extension of shelf-life and enhanced maintenance of food quality (12). In the United States alone, the Centers for Disease Control and Prevention report that each year, roughly 1 in 6 Americans (or 48 million people) gets sick, 128,000 are hospitalized, and 3,000 die of foodborne diseases; this correlates to approximately $77.7 billion in economic loss annually (17). …


Studies In The Atomic Spectrometric Determination And Speciation Of Arsenic In Environmental Samples, Nan Wang Aug 2014

Studies In The Atomic Spectrometric Determination And Speciation Of Arsenic In Environmental Samples, Nan Wang

Doctoral Dissertations

The application of work described in this dissertation, the determination of total and arsenic species in water and rice samples, is of considerable societal importance as large numbers of the citizens of many countries around the world are exposed to potentially harmful concentrations of these carcinogenic compounds by daily consumption. The field of analytical chemistry is crucial to support the operation of any treatment to decrease arsenic concentrations as well as any regulations and legislation regarding arsenic in food and the environment. The current goals of research in trace arsenic measurements and speciation are to increase knowledge of the subject …


Functional Analysis Of Moss Class Viii Myosin And Its Role In Plant Cell Division, Shu-Zon Wu Aug 2014

Functional Analysis Of Moss Class Viii Myosin And Its Role In Plant Cell Division, Shu-Zon Wu

Doctoral Dissertations

The moss Physcomitrella patens is a great model system for studying plant gene function using reverse genetic approaches. It undergoes efficient gene-targeting by homologous recombination, allowing the generation of specific gene knockout and tagging a gene at its endogenous locus. Additionally, RNAi is quite effective in P. patens, providing an effective tool for rapid gene silencing and phenotypic characterization. Taking advantage of these features, this dissertation described the establishment of a system to perform an unbiased gene-by-gene RNAi assay to screen for tip growth phenotypes in P. patens. A small set of RNAi constructs were tested, within them …


Evaluating Predictors Of An Individual’S Dietary Intake Latent Value Under Different Mixed Models, Shuli Yu Aug 2014

Evaluating Predictors Of An Individual’S Dietary Intake Latent Value Under Different Mixed Models, Shuli Yu

Doctoral Dissertations

The accurate estimation of an individual’s usual dietary intake is important since the estimates are essential to uncover the diet-disease relationships. This study explores a more accurate method to estimate an individual’s latent value of usual dietary intake when it is repeatedly measured using a 24-hour dietary recall (24HR) and seven day dietary recall (7DDR), accounting for random measurement error and bias. The performance of the (empirical) predictor of subject’s latent value obtained under the finite population mixed model (FPMM) framework is compared with those obtained under the usual mixed model and the measurement error model through a simulation study. …


Assessing Best Management Practices For Improving Switchgrass Establishment And Production, Amir Sadeghpour Aug 2014

Assessing Best Management Practices For Improving Switchgrass Establishment And Production, Amir Sadeghpour

Doctoral Dissertations

Switchgrass (Panicum virgatum L.) is a C4-grass indigenous to North America being considered as the “model” energy crop. Switchgrass is difficult to establish and first-year stand failure often challenge the large scale production of switchgrass. Reliable establishment methods and effective weed management practices to produce a harvestable biomass in the establishment year are required. Also, to maximize the economic viability of switchgrass production, appropriate nutrient management and harvests are needed. Thus, we conducted researches to improve switchgrass establishment and production. These studies ranged from finding the most promising switchgrass variety to adjusting switchgrass seeding rate, determine the …


Cancer Chemoprevention By Dietary Compounds Targeting Angiogenesis, Wasamon Nutakul Aug 2014

Cancer Chemoprevention By Dietary Compounds Targeting Angiogenesis, Wasamon Nutakul

Doctoral Dissertations

Cancer remains a leading cause of death worldwide. Due to angiogenesis and metastatic potency of cancer, chemotherapies are not adequate for metastatic tumor. We investigated anti-carcinogenic effects of resveratrol in comparison to those of pterostilbene in colon cancer cells. We found superior activities of pterostilbene over resveratrol in growth inhibition as well as apoptosis induction. Higher Intracellular concentration of pterostilbene could contribute to its higher potency in anti-carcinogenesis; however, both resveratrol and pterostilbene failed to inhibit colon cancer cell migration in vitro. Polymethoxylatedflavones (PMFs) found exclusively in citrus fruits have shown inhibitory effects against cancer. We investigated their anti-angiogenic …


Protein Behavior Directed By Heparin Charge And Chain Length, Burcu Baykal Minsky Aug 2014

Protein Behavior Directed By Heparin Charge And Chain Length, Burcu Baykal Minsky

Doctoral Dissertations

Glycosaminoglycans (GAGs), highly charged biological polyelectrolytes, are of growing importance as biomaterials and pharmaceutical drugs due to their immense range of physiological functions. They bind to many proteins; however, the degree of structural selectivity in GAG-protein interactions is largely unknown .Our studies have focused on the importance of heparin (a model GAG) charge and chain length in protein binding in order to explore its potential applications in biofunctional tissue scaffold materials, as polysaccharide drugs in anticoagulation, and as inhibitory agents in protein aggregation. We used electrospray ionization mass spectrometry, capillary electrophoresis, size exclusion chromatography, dynamic/static light scattering and electrostatic protein …


Novel Strategies To Modulate Synaptic Communication And Investigate The Role Of Hdac6 In Alzheimer’S Disease, Kathryne A. Medeiros Aug 2014

Novel Strategies To Modulate Synaptic Communication And Investigate The Role Of Hdac6 In Alzheimer’S Disease, Kathryne A. Medeiros

Doctoral Dissertations

Neuronal communication is mediated by chemical signaling at the synapse. The underlying molecular mechanisms of learning and memory are poorly understood. Very few tools are available to study how memories are formed in the mammalian brain. This dissertation focuses on developing novel strategies to study neural activity. Here we develop and use a chemical-genetic approach to enable target-specific photocontrol of inhibitory synaptic neurotransmission of GABAA receptor subtypes. The tools developed here selectively photocontrolled GABAA receptor subtypes. This enabled the investigation of the functional role these receptor subtypes have in inhibitory synaptic neurotransmission. This dissertation also focuses on identifying …


Microbe-Mineral Relationships And Biogenic Mineral Transformations In Actively Venting Deep-Sea Hydrothermal Sulfide Chimneys, Tzihsuan J. Lin Aug 2014

Microbe-Mineral Relationships And Biogenic Mineral Transformations In Actively Venting Deep-Sea Hydrothermal Sulfide Chimneys, Tzihsuan J. Lin

Doctoral Dissertations

This dissertation uses a combination of microbiology, mineralogy, and geochemistry to understand dissimilatory iron reduction in hyperthermophilic archaea and the role and potential impact of these and other vent microorganisms within active deep-sea hydrothermal vent chimneys. The central objective of the dissertation is to determine if mineral composition and chimney type are among the primary determinants of microbial community composition and hyperthermophilic, dissimilatory iron reducer growth, in addition to other environmental factors such as nutrient availability, temperature, pH, and chlorinity. This is done using samples and organisms collected from the Endeavour Segment of the Juan de Fuca Ridge in the …


Structural Biology And Pharmacology Of Human Cathepsin A And Neuraminidase 1, Nilima Kolli Aug 2014

Structural Biology And Pharmacology Of Human Cathepsin A And Neuraminidase 1, Nilima Kolli

Doctoral Dissertations

Human cathepsin A (also known as Protective Protein/Cathepsin A, PPCA; E.C. 3.4.16.5) is a lysosomal serine carboxypeptidase. Cathepsin A is also involved in a complex with two other lysosomal enzymes: lysosomal neuraminidase (NEU1, E.C. 3.2.1.18) and β-galactosidase (GLB1, E.C. 3.2.1.23). Deficiency in cathepsin A and NEU1 result in the lysosomal storage diseases, galactosialidosis and sialidosis respectively. Deficiency in GLB1 results in GM1 gangliosidosis and Morquio B diseases. Cathepsin A protease activity is spatially regulated by activation of the inactive precursor form to the mature form in the lysosome. Structural studies on the mature form of cathepsin A were performed …