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Role Of Peptidoglycan Modifications In Predation By Bdellovibrio Bacteriovorus 109j, Diane C. Szmiett 2014 The University of Western Ontario

Role Of Peptidoglycan Modifications In Predation By Bdellovibrio Bacteriovorus 109j, Diane C. Szmiett

University of Western Ontario - Electronic Thesis and Dissertation Repository

Bdellovibrio bacteriovorus is a prey dependent bacterium that traverses the outer membrane and peptidoglycan, and enters the periplasmic space of gram negative bacteria, from where it utilizes the cytoplasmic contents for growth. Soluble lytic transglycosylases could be responsible for creating the entry pore during predation. Bacteria can modify their peptidoglycan by the addition of acetate to the C-6 hydroxyl group of the N-acetylmuramic acid residues, which renders the peptidoglycan insensitive to cleavage by lytic transglycosylases. It was hypothesized that the degree of peptidoglycan O-acetylation of the prey cell affects predation efficiency. In this study it was shown that ...


Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka 2014 The University of Western Ontario

Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka

University of Western Ontario - Electronic Thesis and Dissertation Repository

Pharmaceutical residues can reach agricultural land through amendment with animal or human waste. Since 2010, a series of replicated plots received annual applications of ivermectin, monensin and zinc bacitracin, either singly or in a mixture, at 0.1 mg/kg and 10 mg/kg concentrations. I collected soil samples before and after the fourth annual application of pharmaceuticals and assayed them for functional changes and amoA gene abundance, a gene needed for ammonia oxidation. In 2013, I exposed the soils to 100 mg/kg in a laboratory experiment which resulted in acceleration of nitrification. Under 10 mg/kg treatments in ...


Gut Bacteria And Their Influence On Metabolic Disorders, Stephanie Sorbara 2014 Sacred Heart University

Gut Bacteria And Their Influence On Metabolic Disorders, Stephanie Sorbara

Biology Undergraduate Publications

The human gut microbial genome encodes for several metabolic processes that are not encoded for in the human genome. Through the study of metagenomics, mice, and human models, researchers have shown that changes in the gut bacterial composition can generate oxidative stress, release endotoxins, and induce lipogenesis. These pathways can disrupt normal metabolic function, resulting in obesity and other related metabolic disorders such as diabetes. Most of the health implications associated with obesity originate from the biological reactions carried out by the gut bacteria, which are strongly impacted by environmental factors. Probiotics, prebiotics and fecal transplantation are methods that can ...


Enhancing Protein And Enzyme Stability Through Rationally Engineered Site-Specific Immobilization Utilizing Non-Canonical Amino Acids, Jeffrey Chun Wu 2014 Brigham Young University - Provo

Enhancing Protein And Enzyme Stability Through Rationally Engineered Site-Specific Immobilization Utilizing Non-Canonical Amino Acids, Jeffrey Chun Wu

All Theses and Dissertations

The demand for economical, efficient protein production, reuse, and recovery has never been greater due to their versatility in a large variety of applications ranging from industrial chemical manufacturing to pharmaceutical drug production. The applications for naturally and artificially produced proteins include protein drugs and other pharmaceutical products, as biocatalysts in environmentally friendly chemical manufacturing, as enzymes for food processing purposes, and as an essential component in many biomedical devices. However, protein production suffers from many challenges, which include the cost of production, protein stability especially under harsh conditions, and recoverability and reusability of the proteins. The combination of two ...


Diversity And Function Of Sulfur Cycling Microorganisms In Sediments From Subglacial Lake Whillans, Antarctica, Alicia Marie Purcell 2014 University of Tennessee - Knoxville

Diversity And Function Of Sulfur Cycling Microorganisms In Sediments From Subglacial Lake Whillans, Antarctica, Alicia Marie Purcell

Masters Theses

There is a growing consensus that metabolically and phylogenetically diverse assemblages of microorganisms mediate subglacial nutrient and elemental cycling. Subglacial Lake Whillans (SLW), located under 801 m of glacial ice, was recently penetrated using environmentally clean protocols. SLW is a permanently dark, cold (-0.5 °C [degrees Celsius]), and shallow (~2.2 m) freshwater lake beneath the West Antarctic Ice Sheet. The presence and diversity of key functional genes involved in dissimilatory sulfur oxidation and reduction were examined at various depths in two sediment cores taken from SLW. Our data show a diversity of sulfur transformation genes throughout the top ...


Characterization And Role Of Msaabcr In Biofilm Development And Virulence In Staphylococcus Aureus, Gyan Sundar Sahukhal 2014 University of Southern Mississippi

Characterization And Role Of Msaabcr In Biofilm Development And Virulence In Staphylococcus Aureus, Gyan Sundar Sahukhal

Dissertations

Community-acquired, methicillin-resistant Staphylococcus aureus strains often cause localized infections in immune-compromised hosts, but some strains show enhanced virulence leading to severe infections even among healthy individuals with no predisposing risk factors. The genetic basis for this enhanced virulence has yet to be determined. S. aureus possesses a wide variety of virulence factors, the expression of which is carefully coordinated by a variety of regulators. Several virulence regulators have been well characterized, but others have yet to be thoroughly investigated. Previously, the msa gene as a regulator of several virulence genes, biofilm development, and antibiotic ...


Comparative Genomics Of Microbial Chemoreceptor Sequence, Structure, And Function, Aaron Daniel Fleetwood 2014 University of Tennessee - Knoxville

Comparative Genomics Of Microbial Chemoreceptor Sequence, Structure, And Function, Aaron Daniel Fleetwood

Doctoral Dissertations

Microbial chemotaxis receptors (chemoreceptors) are complex proteins that sense the external environment and signal for flagella-mediated motility, serving as the GPS of the cell. In order to sense a myriad of physicochemical signals and adapt to diverse environmental niches, sensory regions of chemoreceptors are frenetically duplicated, mutated, or lost. Conversely, the chemoreceptor signaling region is a highly conserved protein domain. Extreme conservation of this domain is necessary because it determines very specific helical secondary, tertiary, and quaternary structures of the protein while simultaneously choreographing a network of interactions with the adaptor protein CheW and the histidine kinase CheA. This dichotomous ...


Two Distinct Microbial Communities Revealed In The Sponge Cinachyrella, Marie L. Cuvelier, Emily Blake, Rebecca Mulheron, Peter J. McCarthy, Patricia Blackwelder, Rebecca Vega-Thurber, Jose V. Lopez 2014 Florida International University

Two Distinct Microbial Communities Revealed In The Sponge Cinachyrella, Marie L. Cuvelier, Emily Blake, Rebecca Mulheron, Peter J. Mccarthy, Patricia Blackwelder, Rebecca Vega-Thurber, Jose V. Lopez

Oceanography Faculty Articles

Marine sponges are vital components of benthic and coral reef ecosystems, providing shelter and nutrition for many organisms. In addition, sponges act as an essential carbon and nutrient link between the pelagic and benthic environment by filtering large quantities of seawater. Many sponge species harbor a diverse microbial community (including Archaea, Bacteria and Eukaryotes), which can constitute up to 50% of the sponge biomass. Sponges of the genus Cinachyrella are common in Caribbean and Floridian reefs and their archaeal and bacterial microbiomes were explored here using 16S rRNA gene tag pyrosequencing. Cinachyrella specimens and seawater samples were collected from the ...


Comparative Studies Of Oleaginous Fungal Strains (Mucor Circinelloides And Trichoderma Reesei) For Effective Wastewater Treatment And Bio-Oil Production, Anshuman Bhanja, Gauri P. Minde, Sandip S. Magdum, Kalyanraman V. 2014 Pune university

Comparative Studies Of Oleaginous Fungal Strains (Mucor Circinelloides And Trichoderma Reesei) For Effective Wastewater Treatment And Bio-Oil Production, Anshuman Bhanja, Gauri P. Minde, Sandip S. Magdum, Kalyanraman V.

Sandip S. Magdum

iological wastewater treatment typically requires the use of bacteria for degradation of carbonaceous and nitrogenous compounds present in wastewater. The high lipid containing biomass can be used to extract oil and the contents can be termed as bio-oil (or biodiesel or myco-diesel after transesterification). The separate experiments were conducted on actual wastewater samples with 5% v/v inoculum of Mucor circinelloides MTCC1297 and Trichoderma reesei NCIM992 strains. The observed reductions in chemical oxygen demand (COD) were 88.72% and 86.75% in 96 hrs and the observed substrate based biomass yields were 0.21 mg VSS/mg COD and 0 ...


Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Lorraine Jones-Brando Ph. D., Robert H. Yolken M. D., David D. Dunigan Ph. D. 2014 Johns Hopkins University

Chlorovirus Atcv-1 Is Part Of The Human Oropharyngeal Virome And Is Associated With Changes In Cognitive Functions In Humans And Mice, Lorraine Jones-Brando Ph. D., Robert H. Yolken M. D., David D. Dunigan Ph. D.

David D Dunigan Ph. D.

Chloroviruses (family Phycodnaviridae) are large DNA viruses known to infect certain eukaryotic green algae and have not been previously shown to infect humans or to be part of the human virome. We unexpectedly found sequences homologous to the chlorovirus Acanthocystis turfacea chlorella virus 1 (ATCV-1) in a metagenomic analysis of DNA extracted from human oropharyngeal samples. These samples were obtained by throat swabs of adults without a psychiatric disorder or serious physical illness who were participating in a study that included measures of cognitive functioning. The presence of ATCV-1 DNA was confirmed by quantitative PCR with ATCV-1 DNA being documented ...


Herbert W. Conn: Formative Decades Of Microbiology And Evolutionary Biology, Frederick M. Cohan, Alexa Boesel 2014 Wesleyan University

Herbert W. Conn: Formative Decades Of Microbiology And Evolutionary Biology, Frederick M. Cohan, Alexa Boesel

Frederick M. Cohan

Herbert W. Conn (1859–1917) made outstanding contributions to both microbiology and evolutionary biology, reflecting his intellectual command of several biological disciplines. Conn endeavored to make the unseen world of microbes familiar, real, and consequential to members of the general public. He presciently considered the role of bacteria in our own bodies, describing them as being both harmful and beneficial to our health. He also contributed to our understanding of the concept of species, how they originate, and what those ideas might mean in terms of bacterial speciation. In Conn’s spirit, microbial ecologists studying speciation eschew the “species” taxa ...


Herbert W. Conn: Formative Decades Of Microbiology And Evolutionary Biology, Frederick M. Cohan, Alexa Boesel 2014 Wesleyan University

Herbert W. Conn: Formative Decades Of Microbiology And Evolutionary Biology, Frederick M. Cohan, Alexa Boesel

Division III Faculty Publications

Herbert W. Conn (1859–1917) made outstanding contributions to both microbiology and evolutionary biology, reflecting his intellectual command of several biological disciplines. Conn endeavored to make the unseen world of microbes familiar, real, and consequential to members of the general public. He presciently considered the role of bacteria in our own bodies, describing them as being both harmful and beneficial to our health. He also contributed to our understanding of the concept of species, how they originate, and what those ideas might mean in terms of bacterial speciation. In Conn’s spirit, microbial ecologists studying speciation eschew the “species” taxa ...


Pharmacologic Immunomodulation Of Macrophage Activation By Caffeine, Ryan Perry Steck 2014 Brigham Young University - Provo

Pharmacologic Immunomodulation Of Macrophage Activation By Caffeine, Ryan Perry Steck

All Theses and Dissertations

Caffeine is one of the most widely used neurostimulants in the world and there is considerable debate on its effect in immune cells. One of its main targets is proposed to be adenosine receptors which mediate an anti-inflammatory switch in activated immune cells while another target is phosphodiesterase where it acts as an inhibitor. In macrophages, caffeine has been shown to cause both pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes. If the primary effect of caffeine on macrophages were to antagonize adenosine receptors we would expect cells exposed to caffeine to have a prolonged M1 response. However, we show that caffeine ...


From Progesterone In Biopsies To Estimates Of Pregnancy Rates: Large Scale Reproductive Patterns Of Two Sympatric Species Of Common Dolphin, Delphinus Spp. Off California, Usa And Baja, Mexico, Nicholas Marc Kellar, Marisa L. Trego, Susan J. Chivers, Fredrick I. Archer, Wayne L. Perryman 2014 Protected Resources Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration

From Progesterone In Biopsies To Estimates Of Pregnancy Rates: Large Scale Reproductive Patterns Of Two Sympatric Species Of Common Dolphin, Delphinus Spp. Off California, Usa And Baja, Mexico, Nicholas Marc Kellar, Marisa L. Trego, Susan J. Chivers, Fredrick I. Archer, Wayne L. Perryman

Bulletin of the Southern California Academy of Sciences

Blubber progesterone levels were measured in biopsy samples and used to predict the pregnancy status of 507 female common dolphins (204 long-beaked common dolphins, Delphinus capensis, and 303 short-beaked common dolphins, D. delphis). Samples were collected in the coastal waters of the eastern North Pacific between central California, USA and the southern end of Baja California, Mexico. The percentage of females pregnant was similar between the two species: 22.1% (n = 45) of D. capensis and 28.1% (n = 85) of D. delphis. For both species we found strong geographic patterns in pregnancy, suggesting that some areas were more conducive ...


Gammaretroviral Pol Sequences Act In Cis To Direct Polysome Loading And Nxf1/Nxt-Dependent Protein Production By Gag-Encoded Rna, Hanni Bartels, Jeremy Luban 2014 University of Geneva

Gammaretroviral Pol Sequences Act In Cis To Direct Polysome Loading And Nxf1/Nxt-Dependent Protein Production By Gag-Encoded Rna, Hanni Bartels, Jeremy Luban

Open Access Articles

BACKGROUND: All retroviruses synthesize essential proteins via alternatively spliced mRNAs. Retrovirus genera, though, exploit different mechanisms to coordinate the synthesis of proteins from alternatively spliced mRNAs. The best studied of these retroviral, post-transcriptional effectors are the trans-acting Rev protein of lentiviruses and the cis-acting constitutive transport element (CTE) of the betaretrovirus Mason-Pfizer monkey virus (MPMV). How members of the gammaretrovirus genus translate protein from unspliced RNA has not been elucidated.

RESULTS: The mechanism by which two gammaretroviruses, XMRV and MLV, synthesize the Gag polyprotein (Pr65Gag) from full-length, unspliced mRNA was investigated here. The yield of Pr65Gag from a gag-only expression ...


Permaculture Design: On The Practice Of Radical Imagination, Katja Rothe 2014 Berlin University of Arts

Permaculture Design: On The Practice Of Radical Imagination, Katja Rothe

communication +1

Permaculture design is a concept that aims at transforming not only agriculture, but also city planning, architecture, development, etc. In short it aims to change human habitats. It is part of a new ecological paradigm that is currently spreading in popularity from the urban gardening movement to various other alternative movements such as the slow movement, sustainable architecture, etc. Permaculture design defines itself as building on systems theory (as formulated in particular by Howard Thomas Odum and Christopher Alexander). However I would like to propose that the afterlife of systems theory as expressed in the concept of permaculture, first developed ...


Fermented Food: Putting The Power Of Good Health Back Into The Hands Of The People, Marsha L. Thadison 2014 Yesterday's Kitchen 4 Today

Fermented Food: Putting The Power Of Good Health Back Into The Hands Of The People, Marsha L. Thadison

Professional Agricultural Workers Journal

Editors’ Note: At the December 2013 Professional Agricultural Workers Conference, several women were invited to share, information about their unique businesses. One such presenter was Marsha L. Thadison, owner of Yesterday’s Kitchen 4 Today, a company that focuses on promoting functional foods. Thadison shared that food is produce and consumed differently from previous generations. Today's food, she argued, involves many more agricultural inputs that aid in food preservation, extension of shelf life, and promotion of animal health. She espoused the benefits of fermented food.


Snf1 Mediated Phosphorylation And Activation Of Pas Kinase, Bryan D. Badal 2014 Brigham Young University

Snf1 Mediated Phosphorylation And Activation Of Pas Kinase, Bryan D. Badal

All Theses and Dissertations

Nutrient sensing kinases sense available nutrients and regulate cell activity accordingly. Three of these enzymes are AMP regulated kinase (AMPK, or Snf1 in yeast), PAS kinase, and target of rapamycin (TOR), are conserved from yeast to man and have overlapping function. AMPK and Snf1 are important in sensing when nutrient status in the cell is low and down regulating energy consuming pathways. PAS kinase is required for glucose homeostasis in the cell, and responds to glucose levels. TOR senses nutrients such as amino acids and upregulates cell growth pathways primarily through protein synthesis. Due to the varying nature of these ...


The Innate Immune Response In Eisenia Fetida To Microbial Challenges, Aaron Schindler 2014 Minnesota State University, Mankato

The Innate Immune Response In Eisenia Fetida To Microbial Challenges, Aaron Schindler

Journal of Undergraduate Research at Minnesota State University, Mankato

The common earthworm, Eisenia fetida, exhibits a rudimentary immune system. The earthworm needs cellular and chemical responses against a constant microbial exposure from its natural environment. Some cellular and chemical responses are found in the coelomic fluid and have been shown to demonstrate anti-microbial characteristics. This project uses microscopy and modified staining techniques to differentiate and categorize the cellular components found in the coelomic fluid. Following a microbial challenge by Klebsiella pneumoniae, an inflammatory response was initiated. Six groups of earthworms were injected with 0.05 ml of 1.0 x 106 cfu /ml K. pneumoniae on day one and ...


Effect Of Conditioned Medium On The Recovery Of Dormant Mycobacteria In Culture, Kelly E. Rock 2014 Minnesota State University, Mankato

Effect Of Conditioned Medium On The Recovery Of Dormant Mycobacteria In Culture, Kelly E. Rock

Journal of Undergraduate Research at Minnesota State University, Mankato

Mycobacterium avium subsp. paratuberculosis (Mpt) is the etiologic agent of Johne’s disease, a chronic intestinal disease in cattle that threatens the economic viability of dairy farming. Diagnostic culture is typically unrewarding until several years after infection when clinical signs can be observed. This leads to widespread infection within the herd. Difficulty in culturing Mpt may be a result of oxidative damage due to the increased metabolic rate when dormant organisms are recovered in a nutrient rich medium. In order to improve recovery it is believed that some organisms secrete a growth factor in times of environmental stress which enables ...


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