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Articles 113791 - 113820 of 256032

Full-Text Articles in Life Sciences

Precision Drought Stress In Orchards: Rootstock Evaluation, Trunk Hydration And Canopy Temperature, Lance V. Stott May 2017

Precision Drought Stress In Orchards: Rootstock Evaluation, Trunk Hydration And Canopy Temperature, Lance V. Stott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tree fruit crops are of high value, but use a lot of water. Precision irrigation has the potential to save water while simultaneously improving crop quality. The timing and method of precision water stress in various tree fruit crops has been widely studied. However, in order to successfully employ precision irrigation methods in orchards, an accurate measurement of tree water status is required. Currently, stem water potential is the preferred indicator. However, this measurement is tedious and cannot be automated. Because measurements must be taken near solar noon (approximately 1:30 PM MDT in the summer in northern Utah), the number …


Direct And Indirect Effects Of Climate Change On Plant Populations And Communities In Sagebrush Steppe, Andrew R. Kleinhesselink May 2017

Direct And Indirect Effects Of Climate Change On Plant Populations And Communities In Sagebrush Steppe, Andrew R. Kleinhesselink

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rapid climate change presents humanity with a number of big problems. Foremost among these is the sad fact that the climate we will pass on to our children will likely be nothing like the climate that we inherited from our parents. Ecologists have collected solid evidence that climate change has already begun to affect the living things around us and the ecosystems humans depend on. Unfortunately, predicting the future effects of climate change on life on earth is not easy. We focused on three research goals as part of an effort to improve our ability to predict how plants and …


First-Row Transition Metal Sulfides And Phosphides As Competent Electrocatalysts For Water Splitting, Nan Jiang May 2017

First-Row Transition Metal Sulfides And Phosphides As Competent Electrocatalysts For Water Splitting, Nan Jiang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solar energy is a carbon-neutral and renewable energy resource. Its nature of intermittence and unequal distribution requires efficient solar energy capture, conversion, and storage. Solar-driven water splitting to produce hydrogen and oxygen is widely considered as an appealing approach to meet this goal, in which hydrogen acts as a green energy carrier. Water splitting consists of two redox half reactions: hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Both reactions involve the transfer of multiple electrons and protons and possess high energy barriers to proceed at appreciable rates, hence catalysts are needed.

A large number of HER and OER …


Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding May 2017

Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Uinta Basin hookless cactus (Sclerocactus wetlandicus) is a threatened species native to Eastern Utah. The cactus is found in a landscape highly disturbed by non-renewable energy production. To understand the environmental conditions that support natural growth of this cactus, we asked what types of plants were present in the same areas as the cactus, and if the types of plants were different in environments that were disturbed. From our assessment, we determined that the types of plants present in disturbed areas were drastically different from those present in undisturbed locations. Areas previously used for energy production are …


To What Extent Might Beaver Dam Building Buffer Water Storage Losses Associated With A Declining Snowpack?, Konrad Hafen May 2017

To What Extent Might Beaver Dam Building Buffer Water Storage Losses Associated With A Declining Snowpack?, Konrad Hafen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dams built by North American Beaver create natural water storage and slow water as it moves through streams. In portions of streams with beaver dams, these effects have been observed to decrease the peak magnitude of floods and increase base flow during annual summer droughts. In the western United States changes to streamflow patterns have been observed in recent decades with large spring floods coming earlier in the year, causing annual summer droughts to start earlier and last longer. These changes are linked to decreasing snowpack which acts as the most significant natural water storage reservoir by holding onto precipitation …


Foraging Ecology Of Mountain Lions In The Sierra National Forest, California, Bradley C. Nichols May 2017

Foraging Ecology Of Mountain Lions In The Sierra National Forest, California, Bradley C. Nichols

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We conducted this research to gain insight into mountain lion (Puma concolor) prey composition in the Sierra National Forest of California. Managers in the region are concerned with both causes of declines and inability to increase fisher (Pekania pennanti) populations. Research has shown that mountain lions are a threat to fishers due to direct predation of this forest specialist. We radio-collared 5 adult mountain lions in order to determine prey composition and kill rates. As expected, mountain lions selected primarily for mule deer (Odocoileus hemionus). However we did detect other prey such as gray …


Effect Of N-3 And N-6 Polyunsaturated Fatty Acids On Inflammation, Tao Xu May 2017

Effect Of N-3 And N-6 Polyunsaturated Fatty Acids On Inflammation, Tao Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Intake of polyunsaturated fatty acids (PUFA) has changed drastically in the past century in the American diet has received attention due to potential effects on chronic inflammation-related metabolic diseases. In this project, the effects of dietary PUFA content and the n-6 to n-3 ratio on inflammatory responses in the acute and chronic inflammation models were evaluated. The PUFA content was modified on a Western diet background to deliver both n-6 and n-3 intakes at the 10th and 90th percentile of the population in the United States, and models of acute and chronic inflammation were tested in mice model. …


The Behavior And Ecology Of Cursorial Predators And Dangerous Prey: Integrating Behavioral Mechanisms With Population-Level Patterns In Large Mammal Systems, Aimee Tallian May 2017

The Behavior And Ecology Of Cursorial Predators And Dangerous Prey: Integrating Behavioral Mechanisms With Population-Level Patterns In Large Mammal Systems, Aimee Tallian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Driving into Yellowstone National Park for the first time is a moving experience. Gazing over the sweeping landscapes, seeing a geyser erupt 80 feet into the air, and having your first ‘wildlife encounter’, whether that be a 2 ton bull bison aggressively wallowing on his dirt mound, snorting and kicking up dust, or watching a pack of 6 wolves move through a valley off in the distance, pausing to howl in search of their companions. Yellowstone staff wishes to manage our park in a way that preserves these remarkable experiences. In order to effectively manage this dynamic ecosystem, it is …


Low-Pathogenic Influenza A Viruses In North American Diving Ducks Contribute To The Emergence Of A Novel Highly Pathogenic Influenza A(H7n8) Virus, Yifei Xu, Andrew M. Ramey, Andrew S. Bowman, Thomas J. Deliberto, Mary L. Killian, Scott Krauss, Jacqueline M. Nolting, Mia Kim Torchetti, Andrew B. Reeves, Richard J. Webby, David E. Stallknecht, Xiu-Feng Wan May 2017

Low-Pathogenic Influenza A Viruses In North American Diving Ducks Contribute To The Emergence Of A Novel Highly Pathogenic Influenza A(H7n8) Virus, Yifei Xu, Andrew M. Ramey, Andrew S. Bowman, Thomas J. Deliberto, Mary L. Killian, Scott Krauss, Jacqueline M. Nolting, Mia Kim Torchetti, Andrew B. Reeves, Richard J. Webby, David E. Stallknecht, Xiu-Feng Wan

United States Department of Agriculture Wildlife Services: Staff Publications

Introductions of low-pathogenic avian influenza (LPAI) viruses of subtypes H5 and H7 into poultry from wild birds have the potential to mutate to highly pathogenic avian influenza (HPAI) viruses, but such viruses’ origins are often unclear. In January 2016, a novel H7N8 HPAI virus caused an outbreak in turkeys in Indiana, USA. To determine the virus’s origin, we sequenced the genomes of 441 wild-bird origin influenza A viruses (IAVs) from North America and subjected them to evolutionary analyses. The results showed that the H7N8 LPAI virus most likely circulated among diving ducks in the Mississippi flyway during autumn 2015 and …


Assessing Phosphorus Sources With Synoptic Sampling In The Surface Waters Of A Mixed-Use, Montane Watershed, Austin Willis Pearce May 2017

Assessing Phosphorus Sources With Synoptic Sampling In The Surface Waters Of A Mixed-Use, Montane Watershed, Austin Willis Pearce

Theses and Dissertations

Few elements in surface waters are monitored as closely as phosphorus (P) due to its role in the eutrophication and degradation of surface waters. Limiting P mobilization from source areas is, therefore, a central goal of water quality protection plans. But the work of locating sources in mixed-use watersheds is challenged by the spatial and temporal variability of critical source areas (CSAs) of P. Synoptic sampling is a proven method for capturing the spatial variation of water quality parameters in surface waters, though it's not often used to track temporal dynamics across the same study area. Phosphorus fractionation is an …


Insulin And Ketones: Their Roles In Brain Mitochondrial Function, Sheryl Teresa Carr May 2017

Insulin And Ketones: Their Roles In Brain Mitochondrial Function, Sheryl Teresa Carr

Theses and Dissertations

The prevalence of both Type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) is increasing worldwide, and the trends are unfortunately expected to continue. AD has recently been tied with mitochondrial dysfunction and insulin resistance, creating a mechanistic tie between AD and T2DM. Unfortunately, insulin resistance is often increased with aging and therefore, all individuals are at risk of brain mitochondrial dysfunction. Without proper mitochondrial function, the brain will degenerate, causing impaired cognitive function and reduced quality of life. The purpose of this study is two-fold: first, to understand the role of ceramides in insulin-induced brain mitochondrial dysfunction, and; second, …


Interdependency Of Egf And Glp-2 Signaling In Attenuating Mucosal Atrophy In A Mouse Model Of Parenteral Nutrition, Yongjia Feng, Farok R. Demehri, Weidong Xiao, Yu-Hwai Tsai, Jennifer C. Jones, Constance D. Brindley, David W. Threadgill, Jens J. Holst, Bolette Hartmann, Terrence A. Barrett, Daniel H. Teitelbaum, Peter J. Dempsey May 2017

Interdependency Of Egf And Glp-2 Signaling In Attenuating Mucosal Atrophy In A Mouse Model Of Parenteral Nutrition, Yongjia Feng, Farok R. Demehri, Weidong Xiao, Yu-Hwai Tsai, Jennifer C. Jones, Constance D. Brindley, David W. Threadgill, Jens J. Holst, Bolette Hartmann, Terrence A. Barrett, Daniel H. Teitelbaum, Peter J. Dempsey

Internal Medicine Faculty Publications

BACKGROUND & AIMS: Total parenteral nutrition (TPN), a crucial treatment for patients who cannot receive enteral nutrition, is associated with mucosal atrophy, barrier dysfunction, and infectious complications. Glucagon-like peptide-2 (GLP-2) and epidermal growth factor (EGF) improve intestinal epithelial cell (IEC) responses and attenuate mucosal atrophy in several TPN models. However, it remains unclear whether these 2 factors use distinct or overlapping signaling pathways to improve IEC responses. We investigated the interaction of GLP-2 and EGF signaling in a mouse TPN model and in patients deprived of enteral nutrition.

METHODS: Adult C57BL/6J, IEC-Egfrknock out (KO) and IEC-pik3r1KO mice receiving …


Facilitating Pre-Service Teachers To Learn The Mathematical Practices And Engage English Language Learners, Jim Ewing May 2017

Facilitating Pre-Service Teachers To Learn The Mathematical Practices And Engage English Language Learners, Jim Ewing

Journal of Multicultural Affairs

A methods course attempted to help pre-service teachers facilitate the engagement of English language learners (ELLs) in Mathematical Practices from the Common Core State Standards. When 22 elementary pre-service teachers were taught a mathematics lesson in Spanish, most were unable to make sense of the lesson. This made them more aware of challenges ELLs may face when they attempt to engage in Mathematical Practices. The pre-service teachers developed their own strategies to facilitate ELLs. The findings suggest that pre-service teachers not only better empathized with ELLs after being taught in another language, they also learned Mathematical Practices more deeply.


Molecular Subtyping Of Staphylococcus Aureus Isolates From The U.P. Community For The Presence Of Toxin-Encoding Genes, Carol I. Kessel May 2017

Molecular Subtyping Of Staphylococcus Aureus Isolates From The U.P. Community For The Presence Of Toxin-Encoding Genes, Carol I. Kessel

All NMU Master's Theses

Staphylococcus aureus is the most common cause of human bacterial infections; however, humans can also be asymptomatically colonized with S. aureus. Asymptomatic carriers can potentially spread S. aureus infection to others. These infections can range from mild to severe. The pathology of a S. aureus infection is often dependent on which toxins are expressed and the virulence factors with which they are associated. One goal of this study was to isolate S. aureus from healthy, consenting adult volunteers who submitted nasal swabs for culture and qRT-PCR analysis to determine which strains are present in the community. This knowledge could …


Biographical Feature: Thomas F. Smith, Ph.D., Erik Munson May 2017

Biographical Feature: Thomas F. Smith, Ph.D., Erik Munson

Clinical Lab Sciences Faculty Research and Publications

No abstract provided.


Zebrafish As A Model Organism For Ovarian Specific Expression Of Transgenes, Paula Hernandez May 2017

Zebrafish As A Model Organism For Ovarian Specific Expression Of Transgenes, Paula Hernandez

Theses, Dissertations and Culminating Projects

Infertility is a public health issue that affects a large portion of the human population. According to epidemiological studies, 20% of couples worldwide were infertile in 2015 (Turchi, 2015). To understand how to treat infertility and other reproductive disorders in humans, first the mechanism in which vertebrate reproduction occurs must be investigated in a model organism. The zebrafish, Danio reiro is a popular model for reproductive studies (Hill, 2005). For this reason, a transgenic zebrafish was generated with a plasmid that carried 1823 bp of the aromatase (CYP19a) promoter and the Enhanced Green Fluorescent Protein (EGFP) gene. The EGFP gene …


Law Library Blog (May 2017): Legal Beagle's Blog Archive, Roger Williams University School Of Law May 2017

Law Library Blog (May 2017): Legal Beagle's Blog Archive, Roger Williams University School Of Law

Law Library Newsletters/Blog

No abstract provided.


Simplified Reversed Chloroquines To Overcome Malaria Resistance To Quinoline-Based Drugs, Bornface Gunsaru, Steven J. Burgess, Westin Morrill, Jane X. Kelly, Shawheen Shomloo, Martin J. Smilkstein, Katherine May Liebman, David H. Peyton May 2017

Simplified Reversed Chloroquines To Overcome Malaria Resistance To Quinoline-Based Drugs, Bornface Gunsaru, Steven J. Burgess, Westin Morrill, Jane X. Kelly, Shawheen Shomloo, Martin J. Smilkstein, Katherine May Liebman, David H. Peyton

Chemistry Faculty Publications and Presentations

Building on our earlier work of attaching a chemosensitizer (reversal agent) to a known drug pharmacophore, we have now expanded the structure-activity relationship study to include simplified versions of the chemosensitizer. The change from two aromatic rings in this head group to a single ring does not appear to detrimentally affect the antimalarial activity of the compounds. Data from in vitro heme binding and beta-hematin inhibition assays suggest that the single aromatic RCQ compounds retain activities against Plasmodium falciparum similar to those of CQ, although other mechanisms of action may be relevant to their activities.


A Step Towards A "Greener" Dining Services: Procuring Locally For The Health Of Students And The Earth, Jessica Fischer May 2017

A Step Towards A "Greener" Dining Services: Procuring Locally For The Health Of Students And The Earth, Jessica Fischer

Senior Honors Projects

Supporting local food has been a goal of dining services for some time now. Buying local means you know exactly where your food is coming from. Typically the farmer has a direct relationship with the processors that puts pressure on them to abide by all laws and regulations. Secondly, the shorter time between the farm and your table, the less likely that nutrients will be lost during the time it takes to transport food across the country. Third, buying local food builds a sense of community. When you buy direct from a farmer, you’re engaging in a time-honored connection between …


Investigating The Genetic Basis For Hominoid Taillessness, Samantha M. Tickey-Mccrane, Holly Dunsworth, Johanna E. Wegener May 2017

Investigating The Genetic Basis For Hominoid Taillessness, Samantha M. Tickey-Mccrane, Holly Dunsworth, Johanna E. Wegener

Senior Honors Projects

Investigating the Genetic Basis for Hominoid Taillessness:

A Comparative Genetic Approach Across Ten Catarrhine Taxa

Samantha Tickey-McCrane1,2, Johanna E. Wegener2, and Holly Dunsworth1

Honors Thesis Abstract Written by Samantha Tickey-McCrane, Departments of Anthropology & Biology

Advisor: Dr. Holly Dunsworth, Department of Anthropology

How did hominoid tail loss occur? My goals are to test phylogenetic and adaptive hypotheses for tail length variation among macaques, and use those insights to reconstruct the evolution of hominoid taillessness. Further, I aim to ultimately uncover which candidate genes or pathways may be responsible for catarrhine tail loss, and what other traits may be affected by …


Creative Nonnatives: Painting Invasive Insects Of The United States, Monica Tynan May 2017

Creative Nonnatives: Painting Invasive Insects Of The United States, Monica Tynan

Senior Honors Projects

An invasive species is a nonnative organism that may cause damage to an ecosystem. Invasive species cause problems in an environment by outcompeting native organisms for resources or by feeding upon native species. Invasive insects in particular can harm an ecosystem by consuming foliage and decreasing biodiversity. During my experience at the Preisser Lab at the University of Rhode Island, I witnessed rsthand the damage that invasive insects can do to a tree population, and I learned about how ecosystem dynamics can be disrupted by the introduction of a nonnative species.

My project portrays an aesthetically pleasing visualization of several …


Mechanism Of Lck Activation In Driving Leukemia Cell Proliferation, Hannah E. Dobson May 2017

Mechanism Of Lck Activation In Driving Leukemia Cell Proliferation, Hannah E. Dobson

Senior Honors Projects

Leukemia is a type of cancer that develops in blood-forming tissues of the immune system. These tissues can include the bone marrow or sites within the lymphatic system such as the lymph nodes. Leukemia progresses from a mutational event within a white blood cell. Often this mutation alters the cell’s normal life cycle, resulting in uninhibited cell division and growth. With this uncontrolled cell proliferation, mutated white blood cells accumulate and begin interfering with the functioning of healthy cells.

Scientists are unsure of the exact mechanisms required for leukemia development. However, recently scientists identified four characteristic mutations in the protein …


The Relationship Between Body Image And Exercise Type, Ashley Littrell May 2017

The Relationship Between Body Image And Exercise Type, Ashley Littrell

Undergraduate Honors Theses

Exercise can have very beneficial effects on health and body satisfaction, but sometimes a negative body image gets in the way of exercising. Modern society holds certain beauty ideals in high regard, and these standards are often unattainable and unrealistic. These outside pressures to look a certain way can have a very negative effect on an individual’s body image, or the way that a person perceives his or her own appearance. There have been many studies done that have attempted to define the relationship between body image with exercise behaviors (Burger and Diony 2002, Hall and Pearson 2013). Some studies …


Oxidative Quenching Of Photoexcited Ru(Ii)-Bipyridine Complexes By Oxygen, Danielle Rebecca Latham May 2017

Oxidative Quenching Of Photoexcited Ru(Ii)-Bipyridine Complexes By Oxygen, Danielle Rebecca Latham

Undergraduate Honors Theses

An experimental approach was taken in determining the quantum yield of Ruthenium(II) with Oxygen using two different Ru complexes. This reaction results in Ruthenium(III) and O2-. The Coulombic interactions caused by a carboxylate functional was found to increase the yield of charge separation. This was done using a diode to measure the intensity of the completed reaction over a certain time frame. The intensities were turned into concentrations. The concentration over time was used to determine the quantum yield. This information is useful in creating more efficient light emitting diodes.


Salmonella And Aeromonas Contamination In A 303(D) Listed Water Body Compared To Fecal Indicators & Water Quality Parameters, Elizabeth M. Morgan Ms. May 2017

Salmonella And Aeromonas Contamination In A 303(D) Listed Water Body Compared To Fecal Indicators & Water Quality Parameters, Elizabeth M. Morgan Ms.

Undergraduate Honors Theses

Since the passage of the Clean Water Act, concern about surface water quality has increased. Reducing exposure to pathogens and adverse impacts on human health because of contact with surface waters has become the focus of many regulatory agencies. Fecal pollution is often a cause of surface water impairment. Fecal indicators, such as fecal coliforms and Escherichia coli, are used as surrogates to evaluate the presence or absence of fecal pollution. However, a growing body of research has shown that these species lack key characteristics necessary to be adequate indicators. As such, explorations into the efficacy of indicator species …


Elucidating The Effects Of Thiamethoxam Neonicotinoid On Honey Bee Learning Using The Proboscis Extension Response, David J. Shepherd May 2017

Elucidating The Effects Of Thiamethoxam Neonicotinoid On Honey Bee Learning Using The Proboscis Extension Response, David J. Shepherd

Undergraduate Honors Theses

In this study, the effects of the neonicotinoid pesticide, thiamethoxam, are examined through the Proboscis Extension Response (PER) in honey bees (Apis mellifera). PER is a form of classical conditioning applied to honey bees through scent and reward association which quantifies learning rates. Results between groups treated with thiamethoxam did not differ significantly from untreated control groups. Potential reasons for these results are discussed. The method and experimental apparatus for testing the PER assay are also discussed.


Determination Of The Substrate Specificity Of Citrus Paradisi Flavonol Specific 3-O-Glucosyltransferase Mutant D344p, Nathan R. Spaulding May 2017

Determination Of The Substrate Specificity Of Citrus Paradisi Flavonol Specific 3-O-Glucosyltransferase Mutant D344p, Nathan R. Spaulding

Undergraduate Honors Theses

Plants produce a vast array of secondary metabolites. A group of phenolic compounds, the flavonoids, are metabolites ubiquitous among plants and are known to aid in processes such as plant reproduction, UV defense, pigmentation and development. In relation to human health, flavonoids have been found to possess anti-inflammatory, anti-cancer, and antioxidant properties. Flavonoid’s ability to participate in so many interactions is due in part to their subclass variation and further chemical modification. One such modification is glucosylation, where a glucose molecule is added to the flavonoid substrate. The enzymes that catalyze these reactions are known as glucosyltransferases (GT). Citrus paradisi …


The Behavior Of Gammarus Sp. When Exposed To Predation Cues, Will A. Ellis, Trevor Chapman, Joseph Bidwell May 2017

The Behavior Of Gammarus Sp. When Exposed To Predation Cues, Will A. Ellis, Trevor Chapman, Joseph Bidwell

Undergraduate Honors Theses

Predator avoidance behaviors are a critical defense mechanism that can increase the chances of survival for potential prey species. We tested the avoidance behavior of the freshwater amphipod, Gammerus sp., under two different chemical predation cues. The first was the presence of kairomone, which was derived from a species of fish, Gambusia affinis, that was fed a diet exclusively of amphipods. The second predation cue was potential alarm cue derived from macerated conspecific amphipods from the same population as the test species. Response variables included time spent moving after the introduction to the signal as well as the …


Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings May 2017

Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings

Undergraduate Honors Theses

More so than ever, Multiple Drug Resistant (MDR) bacteria are on the rise due to overuse of antibiotics along with natural selection for adaptations that enhance drug-resistant properties. One particular bacterial family, Enterobacteriaceae, has been problematic, exhibiting several bacterial members that have developed a precipitous resistance to modern antibiotics and are also primary causative agents of nosocomial, or hospital acquired, infections. Citrobacter freundii (CF) and Enterobacter cloacae (ECL) are two species of the Enterobacteriaceae family causing significant medical concern due to their role in producing numerous opportunistic infections such as bacteremia, lower respiratory tract infections, urinary tract infections, and endocarditis. …


Cloning And Expression Of C-Terminal Fragment Of Tonb From Rhizobium Leguminosarum Atcc 14479, Brooke E. Baxter May 2017

Cloning And Expression Of C-Terminal Fragment Of Tonb From Rhizobium Leguminosarum Atcc 14479, Brooke E. Baxter

Undergraduate Honors Theses

The TonB-ExbB-ExbD complex is essential for the siderophore mediated acquisition of iron by Gram negative bacteria. The system provides energy from the proton motive force to the outer membrane in order for the iron siderophore complex to enter into the cell. The main protein involved in energy transduction, TonB, has been extensively studied in the species Escherichia Coli. It has been determined that the protein consists of 239 amino acids. In comparison, however, the TonB of Rhizobium leguminosarum consists of 457 amino acids with the same conserved regions. What is in question, therefore, is how the additional amino acids …