Mathematical Modeling Of Gliding Motility And Its Regulation In Myxococcus Xanthus,
2020
Virginia Polytechnic Institute and State University
Mathematical Modeling Of Gliding Motility And Its Regulation In Myxococcus Xanthus, Yirui Chen
Biology and Medicine Through Mathematics Conference
No abstract provided.
The Trichoplusia Ni Gut Microbiome And Its Derivation From The Phyllosphere Of Its Food Plants,
2020
University of North Georgia
The Trichoplusia Ni Gut Microbiome And Its Derivation From The Phyllosphere Of Its Food Plants, Josemaria Garcia, Marisol Escanuela, Swapna Bhat, Evan Lampert
Georgia Journal of Science
Insects are the most abundant and diverse animals on planet Earth and rely on their diverse microbiomes to be so. The insect gut microbiome is vital in the growth and development of many insect species. Trichoplusia ni, the cabbage looper, is a generalist herbivore, but little is known about its microbiome. In this study, a metagenomic analysis of fecal samples was used to determine the effect of diet on the microbiome of T. ni larvae. Larvae were reared on six plant species, the microbiome was sampled from fecal material, and the phyllosphere was sampled from leaves the larvae ate. …
The Physiology And Evolution Of Selenite Respiration In Bacteria,
2020
Duquesne University
The Physiology And Evolution Of Selenite Respiration In Bacteria, Michael Wells
Electronic Theses and Dissertations
The selenium oxyanions selenate (Se(VI)) and selenite (Se(IV)) can be utilized by some bacteria and archaea as terminal electron acceptors in anaerobic respiration. Se(VI) and Se(IV) respiration is mediated by a phylogenetically and ecologically diverse array of organisms, suggesting that selenium respiration is ubiquitous in natural environments. Several respiratory Se(VI) reductases have been characterized in bacteria, revealing that Se(VI) respiration has evolved independently several times in this domain. Se(IV) respiration, in contrast, has yet to be characterized. I have purified and characterized the first respiratory Se(IV) reductase from Bacillus selenitireducens MLS10. The Se(IV) reductase appeared to purify as a single …
Effects Of Warming On Decomposition Of Submerged Plant Litter And Associated Microorganisms In Streamside Channels,
2020
Coastal Carolina University
Effects Of Warming On Decomposition Of Submerged Plant Litter And Associated Microorganisms In Streamside Channels, Kaity Ackerman
Electronic Theses and Dissertations
Surface air temperatures are predicted to increase in the near future, which will likely affect microbial activity and carbon flow in stream ecosystems. I performed an experiment in streamside channels at Coweeta Hydrological Laboratory, NC to assess responses of litter-associated microorganisms to moderate increases in water temperature (5 levels, ambient to +4°C). The objectives of the experiment were to determine: (1) if there are differences in the magnitude of responses to temperature among various microbial parameters and (2) whether microbial responses to temperature vary among plant litter of different carbon quality. Thus, I measured litter decomposition rate, fungal biomass (ergosterol), …
Possible Role Of N-Acetylglucosamine For Induction Of Polyhydroxybutyrate Depolymerase In Streptomyces Sp. Sfb5a,
2020
Bridgewater College
Possible Role Of N-Acetylglucosamine For Induction Of Polyhydroxybutyrate Depolymerase In Streptomyces Sp. Sfb5a, Morgan Todd
Honors Projects
Streptomyces sp. SFB5A is a filamentous, Gram-positive bacterium that makes a polyhydroxybutyrate (PHB) depolymerase to degrade PHB for energy usage. Its life cycle begins as spores germinate to form vegetative mycelia. Starvation prompts formation of aerial mycelia and ultimately spores after 5-7 days. During starvation, Streptomyces may use peptidoglycan hydrolases to degrade its own cell walls, releasing N-Acetylglucosamine (NAG). PHA depolymerase activity is detected during growth of strain SFB5A on NAG as the sole carbon source, suggesting that NAG induces PHA depolymerase synthesis. To test this hypothesis, strain SFB5A was grown for 4 days on PHB, and a colorimetric assay …
Glycogen Accumulation By Wild Type And Bald Mutant Strains Of Streptomyces Sp. Sfb5a During Growth On 3-Hydroxybutyrate,
2020
Bridgewater College
Glycogen Accumulation By Wild Type And Bald Mutant Strains Of Streptomyces Sp. Sfb5a During Growth On 3-Hydroxybutyrate, Mackenzie Francis
Honors Projects
Previous research has shown that Streptomyces sp. SFB5A produces PHA depolymerase and forms aerial hyphae, while the bld4 mutant of this species forms aerial hyphae very poorly and does not produce PHA depolymerase. This effect may be due to the mutant’s inability to sense starvation. Therefore, we hypothesized that the bld4 may also be deficient in formation of glycogen and spores, which are both associated with starvation. To test this hypothesis, we grew the wild type (WT) Streptomyces sp. SFB5A and bld4 in broth cultures containing 3HB. We compared 3HB consumption, glycogen accumulation, PHA depolymerase synthesis, protein accumulation, and spore …
The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas,
2020
University of Arkansas, Fayetteville
The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty
Graduate Theses and Dissertations
Eutrophication of surface waters not only impacts the environment but also water treatment processes, the most significant of which is from the effects of algae. During peak algal growth in many southern U.S. reservoirs, inflows that bring nutrients are at an annual minimum, and phosphorus released from bed-sediments is trapped in the hypolimnion. Littoral areas, described as the most productive zone of the lake, may be a possible source of phosphorus that fuels algal growth in the reservoir. I studied an isolated shallow cove in the War Eagle Creek arm of Beaver Lake in Northwest Arkansas to measure, quantify, and …
Effects Of Light, Nutrients, And Salts On Microbial Biofilm Productivity And Detrital Processing In Aquatic Mesocosms,
2020
University of Arkansas, Fayetteville
Effects Of Light, Nutrients, And Salts On Microbial Biofilm Productivity And Detrital Processing In Aquatic Mesocosms, Bethanie Brooke Howard-Parker
Graduate Theses and Dissertations
Anthropogenic activities associated with urbanization, agriculture, and resource extraction continue to increase to support increasing needs of the growing population. These activities increase the amounts of pollutants entering freshwater streams and put aquatic ecosystems at structural and functional risk. Aquatic microbes play an important role in detrital processing in streams as a key linkage in moving carbon from detrital stocks into aquatic food webs. My research investigates the effects of light, nutrients, and salts on detrital microbes and decomposition in freshwaters using a mesocosm approach. In chapter one, I modified a current priming effect (PE) hypothesis model to include light …
A Comparative Taxonomic And Diversity Study Of Litter-Associated Fungi In Northwest Arkansas Forests,
2020
University of Arkansas, Fayetteville
A Comparative Taxonomic And Diversity Study Of Litter-Associated Fungi In Northwest Arkansas Forests, Rajaa Abdulrazzaq Abbas Al Aanbagi
Graduate Theses and Dissertations
Fungi are taxonomically the most species-rich group of organisms on the earth, ecologically occupy distinctive niches and interact with diverse other organisms throughout their biogeographic distributions and functionally play key roles through their various lifestyles. Plant litter, in particular, is a keystone component in ecosystems and provides heterogeneous microhabitats for the often overlooked litter-decomposing fungi and other organisms on the floor of temperate deciduous forests. Litter fungi involve indirect interactions with the plant, soil and whole food web network. However, the community structure and functions of litter-associated fungi as well as patterns of species richness distributed across various litter microhabitats …
Elucidating The Molecular Pathways Involved In The Fitness And Water Stress Response Of Pseudomonas Synxantha 2-79 In The Plant Rhizosphere,
2020
University of Southern Mississippi
Elucidating The Molecular Pathways Involved In The Fitness And Water Stress Response Of Pseudomonas Synxantha 2-79 In The Plant Rhizosphere, Clint Henry D. Pablo
Master's Theses
Pseudomonas synxantha 2-79 is a biocontrol agent that represents beneficial indigenous rhizobacteria that are broadly distributed in the Pacific Northwest, USA and flourish in the rhizosphere of commercially grown wheat under surprisingly arid conditions. The molecular adaptation of 2-79-like bacteria to plants growing in dry soils is poorly understood. We hypothesized that the ability of 2-79 to colonize and persist in the rhizosphere of water-stressed plants is underpinned by the formation of hydrating biofilms and the utilization of root exudates that contain plant-derived osmoprotectants called quaternary ammonium compounds (QACs). We tested this hypothesis by identifying waters stress response pathways in …
The Effects Of Light On The Bacterial Biomass Of Decomposing Leaf Litter In Freshwater,
2020
The University of Southern Mississippi
The Effects Of Light On The Bacterial Biomass Of Decomposing Leaf Litter In Freshwater, Savannah L. Underwood
Honors Theses
Recent evidence has suggested that the presence of light (and in conjuction, periphytic algae) stimulates the growth and production of bacteria on decaying plant litter. However, the current method of measuring bacterial biomass, flow cytometry, drastically underestimates the bacterial biomass levels associated with litter samples. To determine and correct for this underestimation, the present study determined conversion factors using direct counting methods via epifluorescence microscopy. These conversion factors were then applied to flow cytometry counts for seven different studies. The studies analyzed the effects of light and other covarying factors on the bacterial biomass associated with various samples of leaf …
Soil Microbial Diversity And Litter Decomposition Increase With Time Since Land Use Disturbance In Tropical Montane Forests Of Malaysian Borneo,
2020
University of Arkansas, Fayetteville
Soil Microbial Diversity And Litter Decomposition Increase With Time Since Land Use Disturbance In Tropical Montane Forests Of Malaysian Borneo, Renee Sniegocki
Graduate Theses and Dissertations
Logging and forest conversion are occurring at alarming rates in the tropical forests of Southeast Asia. These disturbances alter soil chemistry, microbial diversity, and disrupt carbon cycling through shifts in litter decomposition. Direct links between microbial diversity and soil properties such as pH are well established; however, the indirect impacts of logging and forest conversion on microbial diversity and litter decomposition are poorly understood. We used surface (5 cm) soil to assess soil physicochemical properties, next-generation DNA sequencing to assess soil microbial diversity, and standardized litterbags to assess litter decomposition stabilization at five sites along a land use disturbance gradient …
Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes,
2020
University of Connecticut
Identification And Analysis Of Feather Degrading Bacteria: A Search For Keratinase Genes, Nehal Navali
Honors Scholar Theses
Over two million tons of feather waste is generated annually by the poultry industry, the majority of which goes into landfills due to the difficulty of degrading its major component keratin. Although a portion of feather waste is eliminated via incineration or chemical treatment, the use of Feather Degrading Bacteria (FDB) has been proposed as a cheap and eco-friendly alternative. FDBs have been consistently isolated from the feather microbiome of birds and contain genes coding for the specialized protein keratinase which is able to degrade feathers. By doing so, feather waste, which is rich in nutrients, can be repurposed as …
Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments,
2020
The University of Southern Mississippi
Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments, Shuo Shen
Dissertations
As antibiotic resistance genes in aquatic environment have been increasing across the world, affecting water quality and public health, many studies documented concentrations of antibiotic resistance genes and some studies discussed their potential drivers. However, systematic and quantitative reviews that link antibiotic resistance genes (ARGs) to anthropogenic and environmental factors are limited. Nevertheless, this information will be important for developing regulation policy on controlling antibiotic use and therefore reducing potential risks to antibiotic resistance. I conducted meta-analysis of ARGs concentration at a global scale using Bayesian inference to explore climatic and socio-economic factors as drivers. I found local-scale climatic variables …
Comparison Of Three Analytical Techniques For General Characterisation Of Selected Algae And Cyanobacteria,
2020
Universiti Malaya
Comparison Of Three Analytical Techniques For General Characterisation Of Selected Algae And Cyanobacteria, Mohamed Iqbal Suhaina Nashath
Student Works (2020-2029)
Algae and cyanobacteria maintain the oxygenation of earth, and are utilised as biofuels, biofertilizers and nutrition feed. The characterisation of algae and cyanobacteria through conventional methods require technical expertise, laborious sample preparation, and moderately expensive instruments and reagents. Hence, in this study, selected bioanalytical techniques with minimal sample preparation were incorporated, to simplify the characterisation of algae and cyanobacteria. The objectives of this research were to study the phylogenetic relationship of the selected algae and cyanobacteria via the 23S plastid ribosomal ribonucleic acid (rRNA) and 18S rRNA biomarkers; to validate the presence of the microcystin synthetase (mcy) gene cluster encoding …
Effect Of Zinc On Microcystis Aeruginosa And Its Toxin Production,
2020
Seton Hall University
Effect Of Zinc On Microcystis Aeruginosa And Its Toxin Production, Jose L. Perez
Seton Hall University Dissertations and Theses (ETDs)
Cyanobacteria harmful algal blooms (CHABs) are globally increasing biomasses of detrimental cyanobacteria due to anthropogenic water phosphorous and nitrogen loading and climate change. CHABs often produce secondary metabolites, cyanotoxins, that cause harmful effects to organisms, most water systems, and socioeconomic infrastructures. Additionally, the presence of heavy metal pollutant runoff in CHAB affected environments may result in CHAB population changes – aggravating toxigenicity. Zinc metal resistance and stress response were studied in microcystin (MC) cyanotoxin-producing Microcystis aeruginosa UTEX LB 2385 (M. aeruginosa UTEX LB 2385) and non-MC producing Microcystis aeruginosa UTEX LB 2386 (M. aeruginosa UTEX LB 2386) cyanobacteria. Molecular analysis …
Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata,
2020
Harvard University
Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce
Publications and Research
Elevation is an important determinant of ecological community composition. It integrates several abiotic features and leads to strong, repeatable patterns of community structure, including changes in the abundance and richness of numerous taxa. However, the influence of elevational gradients on microbes is understudied relative to plants and animals. To compare the influence of elevation on multiple taxa simultaneously, we sampled phytotelm communities within a tropical pitcher plant (Nepenthes mindanaoensis) along a gradient from 400 to 1200 m a.s.l. We use a combination of metabarcoding and physical counts to assess diversity and richness of bacteria, micro-eukaryotes, and arthropods, and compare the …
Microbiota Accessible Carbohydrates And Susceptibility To Clostridioides Difficile Infection,
2020
University of Nebraska-Lincoln
Microbiota Accessible Carbohydrates And Susceptibility To Clostridioides Difficile Infection, Keegan Schuchart, Jennifer Auchtung, Thomas Auchtung
UCARE: Research Products
This experiment looked into the effects of dietary microbiota accessible carbohydrates (MACs)on the composition of human GI microbe colonies and their susceptibility to pathogen infection. Three different concentrations of MAC ingrained media were tested in mini bioreactor arrays, treated with antibiotics, infected with Clostridioides difficile, then allowed to recover. Microbe community was examined for strain composition and diversity before and after the antibiotic treatment and Clostridioides difficile infection. After the initial mini bioreactor run, individual isolates were investigated in their ability to respond to specific MACs Arabinoglactina, Inulin, and Soluble starch at experimental concentrations.
Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek,
2020
Georgia College & State University
Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek, Katie M. Johnson
Biology Theses
Surface freshwater is a scarce resource. Due to the scarcity and necessity of this resource, it is imperative that its quality is routinely monitored. One way of monitoring water quality is through biological assessments, which include examining algal assemblages. Regionally, little remains known of algal taxa in the southeastern United States. In the past, the Academy of Natural Sciences of Philadelphia (ANSP) conducted biological assessments along the Savannah River finding Gomphonema parvulum (Kützing) Kützing 1849 to be a dominant taxon rendering assessments inconclusive. Recent studies have provided evidence that species complexes and semi-cryptic taxa have been identified within the Gomphonema …
Quantifying Nutrient Throughput And Dom Production By Algae In Continuous Culture,
2020
Case Western Reserve University
Quantifying Nutrient Throughput And Dom Production By Algae In Continuous Culture, Anne Willem Omta
Faculty Scholarship
Freshwater and marine algae can balance nutrient demand and availability by regulating uptake, accumulation and exudation. To obtain insight into these processes under nitrogen (N) and phosphorus (P) limitation, we reanalyze published data from continuous cultures of the chlorophyte Selenastrum minutum . Based on mass budgets, we argue that much of the non-limiting N and P had passed through the organisms and was present as dissolved organic phosphorus or nitrogen (DOP or DON). We construct a model that describes the production of biomass and dissolved organic matter (DOM) as a function of the growth rate. A fit of this model …
