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Cyanobacteria, Algae And Microfungi Present In Biofilm From Božana Cave (Serbia), Slađana Popović, Gordana Subakov Simić, Miloš Stupar, Nikola Unković, Dragana Predojević, Jelena Jovanović, Milica Ljaljević Grbić 2015 University of Belgrade, Faculty of Biology

Cyanobacteria, Algae And Microfungi Present In Biofilm From Božana Cave (Serbia), Slađana Popović, Gordana Subakov Simić, Miloš Stupar, Nikola Unković, Dragana Predojević, Jelena Jovanović, Milica Ljaljević Grbić

International Journal of Speleology

Phototrophic microorganisms (cyanobacteria and algae) and microfungi, were identified from biofilm on the walls of the entrance of BožanaCavein west Serbia. Temperature, relative humidity and light intensity were measured, and chlorophyll a content determined. Light intensity differed from the entrance inwards. However, Chl a content was not proportional to light intensity, instead it was positively correlated to biofilm weight. Biofilm samples from two sites were also observed using a scanning electron microscope. Coccoid forms of cyanobacteria were abundant at the sampling site with the lowest light intensity, while members of the order Nostocales were predominant at the sampling site with ...


The Shellfish Corner--Shellfish Sanitation And The Price Of Shellfish, Michael A. Rice 2015 University of Rhode Island

The Shellfish Corner--Shellfish Sanitation And The Price Of Shellfish, Michael A. Rice

Michael A Rice

Prices of raw molluscan shellfish in different countries around the world are tied to perceived risk of becoming ill if consumed. Wholesale prices of oysters in the southern New England from 1880 to 2010 are analyzed in relation to introduction of flush toilets and sewer systems in the early 20th Century, the initiation of the US National Shellfish Sanitation Program in 1925 and renewed consumer interest in consuming raw shellfish in the latter half of the 20th Century.


Concomitant Uptake Of Antimicrobials And Salmonella In Soil And Into Lettuce Following Wastewater Irrigation, J. Brett Sallach, Yuping Zhang, Laurie Hodges, Daniel D. Snow, Xu Li, Shannon L. Bartelt-Hunt 2015 University of Nebraska--Lincoln

Concomitant Uptake Of Antimicrobials And Salmonella In Soil And Into Lettuce Following Wastewater Irrigation, J. Brett Sallach, Yuping Zhang, Laurie Hodges, Daniel D. Snow, Xu Li, Shannon L. Bartelt-Hunt

Civil Engineering Faculty Publications

The use of wastewater for irrigation may introduce antimicrobials and human pathogens into the food supply through vegetative uptake. The objective of this study was to investigate the uptake of three antimicrobials and Salmonella in two lettuce cultivars. After repeated subirrigation with synthetic wastewater, lettuce leaves and soil were collected at three sequential harvests. The internalization frequency of Salmonella in lettuce was low. A soil horizon-influenced Salmonella concentration gradient was determined with concentrations in bottom soil 2 log CFU/g higher than in top soil. Lincomycin and sulfamethoxazole were recovered from lettuce leaves at concentrations as high as 822 ng ...


Determining The Fate Of Non-O157 Shiga Toxin-Producing Escherichia Coli In Dairy Compost During Storage Using The Optimized Detection Method, Hongye Wang 2015 Clemson University

Determining The Fate Of Non-O157 Shiga Toxin-Producing Escherichia Coli In Dairy Compost During Storage Using The Optimized Detection Method, Hongye Wang

All Theses

Shiga toxin-producing Escherichia coli (STEC), a member of Enterobacteriaceae family, has been recognized as emerging pathogens. Dairy compost is commonly applied to farmland as a soil amendment. Despite the agricultural benefit of manure-based soil amendment, the inadequately treated compost can contribute to fresh produce contamination on the farm. Moreover, the epidemiological results showed that the non-O157 STEC cases have surpassed those of E. coli O157. Therefore, it is critical to evaluate the behavior of non-O157 STEC strains in the dairy manure-based compost. The objectives of this study were to: 1) optimize a culturing method for detecting non-O157 STEC from dairy ...


Characterization Of Biofilms On Medical Device Materials With Application To Reusable Surgical Instruments, Amanda Macaluso 2015 Clemson University

Characterization Of Biofilms On Medical Device Materials With Application To Reusable Surgical Instruments, Amanda Macaluso

All Theses

Reusable medical devices or reprocessed single-use devices are original medical devices that have been used once and then are cleaned, sterilized, and remanufactured for the purpose of an additional single use on a single patient [4]. Improperly reprocessed devices are a significant contributor to hospital-associated infections [4]. Challenges that hinder reprocessing are related to the complexity of reusable medical device design, the necessary validation of cleaning protocols required by the U.S Food and Drug Administration (FDA), the impact of human factors throughout the reprocessing cycle, as well as economic factors within new business models that are centered on reprocessing ...


The Effects Of Probiotics Supplementation On Health Using Caenorhabditis Elegans As A Model System, Miranda Klees 2015 Clemson University

The Effects Of Probiotics Supplementation On Health Using Caenorhabditis Elegans As A Model System, Miranda Klees

All Theses

The 'Western Diet,' prominent among developed nations, often refers to a diet rich in meat proteins and refined sugars. Western society may in part be plagued with obesity and obesity related diseases due to a diet enriched with glucose. With an increasing glycemic index observed in Western society, it comes to no surprise that obesity, diabetes, heart disease, and other obesity related diseases are on the rise. The Centers for Disease Control and Prevention describes obesity as an epidemic, affecting more than 35% of U.S. citizens. Shortened lifespan and increased susceptibility to pathogens are associated with these diseases and ...


Inhibition Of Vibrio Cholerae Biofilm Formation By Water-Soluble Cranberry Extracts, Daniel Pederson 2015 Clemson University

Inhibition Of Vibrio Cholerae Biofilm Formation By Water-Soluble Cranberry Extracts, Daniel Pederson

All Theses

Vibrio cholerae, a Gram-negative bacterium found in natural aquatic environments, is the causative agent of cholera, a severe diarrheal disease most commonly spread through drinking water. An essential component to this pathogen's success and persistence in the environment is its ability to attach to both biotic and abiotic surfaces via biofilm formation. Biofilms not only aid in surface attachment, but also provide a barrier that protects and enhances survival. Water-soluble extracts from the North American cranberry (Vaccinium macrocarpon) were found to dramatically inhibit V. cholerae biofilm formation at a low concentration of 2mg/ml. This inhibition was not due ...


In The Social Amoeba, Dictyostelium Discoideum , Density, Not Farming Status, Determines Predatory Success On Unpalatable Escherichia Coli, Susanne DiSalvo, Debra A. Brock, jeff smith, David C. Queller, Joan E. Strassmann 2014 Washington University in St Louis

In The Social Amoeba, Dictyostelium Discoideum , Density, Not Farming Status, Determines Predatory Success On Unpalatable Escherichia Coli, Susanne Disalvo, Debra A. Brock, Jeff Smith, David C. Queller, Joan E. Strassmann

Biology Faculty Publications

Background
The social amoeba Dictyostelium discoideum interacts with bacteria in a variety of ways. It is a predator of bacteria, can be infected or harmed by bacteria, and can form symbiotic associations with bacteria. Some clones of D. discoideum function as primitive farmers because they carry bacteria through the normally sterile D. discoideum social stage, then release them after dispersal so the bacteria can proliferate and be harvested. Some farmer-associated bacteria produce small molecules that promote host farmer growth but inhibit the growth of non-farmer competitors. To test whether the farmers’ tolerance is specific or extends to other growth inhibitory ...


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 ...


Bone Marrow Stromal Antigen 2 Expressed In Cancer Cells Promotes Mammary Tumor Growth And Metastasis, Wadie D. Mahauad-Fernandez, Kris A. DeMali, Alicia K. Olivier, Chioma M. Okeoma 2014 University of Iowa

Bone Marrow Stromal Antigen 2 Expressed In Cancer Cells Promotes Mammary Tumor Growth And Metastasis, Wadie D. Mahauad-Fernandez, Kris A. Demali, Alicia K. Olivier, Chioma M. Okeoma

Department of Microbiology Publications

Introduction: Several innate immunity genes are overexpressed in human cancers and their roles remain controversial. Bone marrow stromal antigen 2 (BST-2) is one such gene whose role in cancer is not clear. BST-2 is a unique innate immunity gene with both antiviral and pro-tumor functions and therefore can serve as a paradigm for understanding the roles of other innate immunity genes in cancers.

Methods: Meta-analysis of tumors from breast cancer patients obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets were evaluated for levels of BST-2 expression and for tumor aggressiveness. In vivo, we examined ...


Transcriptomic And Proteomic Dynamics In The Metabolism Of A Diazotrophic Cyanobacterium, Cyanothece Sp. Pcc 7822 During A Diurnal Light-Dark Cycle, Louis A. Sherman 2014 lsherman@purdue.edu

Transcriptomic And Proteomic Dynamics In The Metabolism Of A Diazotrophic Cyanobacterium, Cyanothece Sp. Pcc 7822 During A Diurnal Light-Dark Cycle, Louis A. Sherman

Louis A Sherman

Background: Cyanothece sp. PCC 7822 is an excellent cyanobacterial model organism with great potential to be applied as a biocatalyst for the production of high value compounds. Like other unicellular diazotrophic cyanobacterial species, it has a tightly regulated metabolism synchronized to the light-dark cycle. Utilizing transcriptomic and proteomic methods, we were able to quantify the relationships between transcription and translation underlying central and secondary metabolism in response to nitrogen free, 12 hour light and 12 hour dark conditions.

Results: By combining mass-spectrometry based proteomics and RNA-sequencing transcriptomics, we quantitatively measured a total of 6766 mRNAs and 1322 proteins at four ...


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 ...


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 ...


Spring Thaw Ionic Pulses Boost Nutrient Availability And Microbial Growth In Entombed Antarctic Dry Valley Cryoconite Holes, Jon Telling, Alexandre M. Anesio, Martyn Tranter, Andrew G. Fountain, Thomas H. Nylen, Jon Hawkings, Virendra B. Singh, Preeti Kaur, Michaela Musilova, Jemma L. Wadham 2014 University of Bristol

Spring Thaw Ionic Pulses Boost Nutrient Availability And Microbial Growth In Entombed Antarctic Dry Valley Cryoconite Holes, Jon Telling, Alexandre M. Anesio, Martyn Tranter, Andrew G. Fountain, Thomas H. Nylen, Jon Hawkings, Virendra B. Singh, Preeti Kaur, Michaela Musilova, Jemma L. Wadham

Geology Faculty Publications and Presentations

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of spring thaw toward fully melted holes. The cryoconite holes had a mean isolation age from the glacial drainage system of 3.4 years, with an increasing mass of aqueous nutrients (dissolved organic carbon, total nitrogen, total phosphorus) with longer isolation ...


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 ...


Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson 2014 California Polytechnic State University - San Luis Obispo

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses and Project Reports

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced ...


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 ...


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