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Full-Text Articles in Physical Sciences and Mathematics

Synthesis Of Bacterial Glycerophospholipids For Biomembrane Model Studies: A Means To Advanced Biofuels, Felix Adulley Dec 2023

Synthesis Of Bacterial Glycerophospholipids For Biomembrane Model Studies: A Means To Advanced Biofuels, Felix Adulley

Electronic Theses and Dissertations

To reduce reliance on fossil fuels, sustainable biofuels are being pursued, especially advanced biofuels like 1-butanol that have higher energy content and greater compatibility with existing infrastructure than ethanol. A persistent challenge is the yield-limiting toxicity of biofuels and process solvents, such as tetrahydrofuran, to the microbes that ferment biomass into biofuel. The cell membrane is a focal point of toxicity, and understanding how it interacts with fuels and solvents is key to improving yield. Phospholipid bilayers are the core of biomembranes, and model biomembranes of defined composition provide the ideal platform for biophysical studies. To this end, glycerophospholipids characteristic …


Geometric Morphometric Analysis Of Modern Viperid Vertebrae Facilitates Identification Of Fossil Specimens, Lance D. Jessee Aug 2023

Geometric Morphometric Analysis Of Modern Viperid Vertebrae Facilitates Identification Of Fossil Specimens, Lance D. Jessee

Electronic Theses and Dissertations

Snake vertebrae are common in the fossil record, whereas cranial remains are generally fragile and rare. Consequently, vertebrae are the most commonly studied fossil element of snakes. However, identification of snake vertebrae can be problematic due to extensive variation. This study utilizes 2-D geometric morphometrics and canonical variates analysis to 1) reveal variation between genera and species and 2) classify vertebrae of modern and fossil eastern North American Agkistrodon and Crotalus. The results show that vertebrae of Agkistrodon and Crotalus can reliably be classified to genus and species using these methods. Based on the statistical analyses, four of the …


A Programmatic Geographic Information Systems Analysis Of Plant Hardiness Zones, Andrew Bowen May 2023

A Programmatic Geographic Information Systems Analysis Of Plant Hardiness Zones, Andrew Bowen

Electronic Theses and Dissertations

The Plant Hardiness Zone Map consists of thirteen geographical zones that describe whether a plant can survive based on average annual minimal temperatures. As climate change progresses, minimum temperatures in all regions are expected to change. This work programmatically evaluates predicted future climate projection data and converts it to United States Department of Agriculture-defined hardiness zones. Through the next 80 years, hardiness zones are projected to move poleward; in effect, colder zones will lose area and warmer zones will gain area globally. Some implications include changes in crop growing degree days, which could alter crop productivity, migration and settlement of …


The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier Aug 2022

The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier

Electronic Theses and Dissertations

The national mammal of the United States, the American Bison (Bison bison) was once nearly extinct. Populations have recovered to the degree that thousands roam the Great Plains today. Due to their large numbers and body size, this species has an oversized impact on the ecological communities where it lives and is considered a keystone herbivore in modern North American grasslands. This study explores the detailed, seasonally resolved, paleoecology of seven bison from the Greater Yellowstone Ecosystem during the Late Holocene through stable isotope analyses and species niche modeling. Isotopic analyses of δ13C, δ15N, …


Community Structure Analysis Of Turtles With Application To The Early Pliocene Gray Fossil Site, Julian Conley Aug 2022

Community Structure Analysis Of Turtles With Application To The Early Pliocene Gray Fossil Site, Julian Conley

Electronic Theses and Dissertations

Turtles are important components of ecosystems around the world, with diverse ecological niches and adaptations. However, there are few detailed studies of how turtle community structure reflects local environments. This project applied techniques of community structure analysis to sites across the United States to infer past ecosystem and environmental conditions of the early Pliocene Gray Fossil Site (GFS) in northeastern Tennessee based on the ancient turtle community. Results indicate extant turtle community structure closely reflects environmental conditions, and that ancient turtle communities can be used to infer climate and habitat conditions of past ecosystems. Application to the GFS turtle community …


Community Structure Analysis Of Mammals Found At The Gray Fossil Site, Tn, Sarah Clark May 2022

Community Structure Analysis Of Mammals Found At The Gray Fossil Site, Tn, Sarah Clark

Electronic Theses and Dissertations

The early Pliocene Gray Fossil Site (GFS) is a biodiverse site with a unique faunal assemblage that represents one of few sites of its age in eastern North America. A community structure analysis of the mammals at GFS was done to characterize species and better understand the paleoenvironment. Data and was gathered from twenty modern communities and five late Neogene sites to compare with GFS. Species from these 26 sites were categorized by body size, locomotor mode, cheek tooth crown height, and diet to characterize niches occupied. Descriptive statistics contrasted proportions of species within categories across communities. Discriminant function analyses …


Distinguishing Mustela From Neogale (Mustelidae) Through Both A Qualitative And Quantitative Analysis Of Skull And Tooth Morphology, Ronald W. Peery Dec 2021

Distinguishing Mustela From Neogale (Mustelidae) Through Both A Qualitative And Quantitative Analysis Of Skull And Tooth Morphology, Ronald W. Peery

Electronic Theses and Dissertations

Weasels and mink (Mustela and Neogale) can be difficult to distinguish osteologically due to similarities in morphology, thus suggesting the need for an accurate tool in distinguishing among taxa. This study utilized a combination of character state and stepwise discriminant function (DFA) analyses to examine potential distinguishing features of skull and tooth morphology. Measurements and ratios were collected from all 18 extant musteline species, as well as the extinct Neovison macrodon, Mustela rexroadensis, Mustela meltoni, Mustela gazini, and Mustela jacksoni. Unidentified musteline specimens from the Gray Fossil Site were also included. Results of …


Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause Aug 2020

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning the latest Pleistocene …


A Tale Of Two Species: Black-Tailed And White-Tailed Prairie Dog Biogeography From The Last Interglacial To 2070, April Dawn Bledsoe May 2020

A Tale Of Two Species: Black-Tailed And White-Tailed Prairie Dog Biogeography From The Last Interglacial To 2070, April Dawn Bledsoe

Electronic Theses and Dissertations

Ecological niche models (ENMs) were created for White-tailed and Black-tailed prairie dogs and projected into the Last Interglacial (LI), the Last Glacial Maximum (LGM), and mid-Holocene (mid-H) to discern possible past suitable habitat for both species. Additionally, ENMs were projected into the future year 2070 representative concentration pathways (RCPs) 2.6 and 8.5 to discern how climate change may affect future habitat suitability. Kernel density estimations, minimum convex polygons, and median distribution centers of White-tailed and Black-tailed occurrence records were examined between time-periods to discern the effects of anthropogenic westward expansion on both species’ distributions. Current ENMs were constructed from commonly …


Ontogenetic And Adult Shape Variation In The Endocast Of Tapirus: Implications For T. Polkensis From The Gray Fossil Site, Thomas M. Gaetano May 2020

Ontogenetic And Adult Shape Variation In The Endocast Of Tapirus: Implications For T. Polkensis From The Gray Fossil Site, Thomas M. Gaetano

Electronic Theses and Dissertations

Endocranial morphology provides evidence of sensory ecology and sociality of extinct vertebrates. The Earliest Pliocene Gray Fossil Site (GFS) of NE Tennessee features a conspicuous dominance of skeletal elements belonging to the dwarf tapir, Tapirus polkensis. Numerous individuals in one fossil locality often suggests gregarious behavior, but sociality in T. polkensis contradicts behavior documented for extant Tapirus species. I test T. polkensis for variation in sensory and social ecology using computed tomography and 3D digital endocasts from an ontogenetic sequence. I compare the T. polkensis endocasts with extant Tapirus species using Encephalization Quotients (EQs) and 3D geometric morphometrics. Results …


Encephalization In Commensal Raccoons: A Unique Test Of The Cognitive Buffer Hypothesis, Peter M. Anderson May 2020

Encephalization In Commensal Raccoons: A Unique Test Of The Cognitive Buffer Hypothesis, Peter M. Anderson

Electronic Theses and Dissertations

This study investigated selective pressures associated with encephalization in mammals and discussed broader implications. Relative brain size as measured by EQ (Encephalization Quotient) was compared between ecological categories. Omnivores had higher average EQ than ecological specialists. Since specialists are disproportionately affected by extinction events, selection for ecological generalism is proposed as encephalization mechanism. This mechanism may reinforce the more widely known Cognitive Buffer Hypothesis (CBH)—the idea that possessing relatively large brains has buffered lineages against environmental change. CBH is tested here by comparing EQs in Procyon lotor (raccoon) in urban and rural environments. CBH predicts that raccoons in the most …


Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap May 2019

Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap

Electronic Theses and Dissertations

Continental scale studies on ungulate crown heights in relation to climate and habitat changes have revealed a correlation between increasing hypsodonty and a shift to more arid environments. Small mammals have been shown to adapt to changing habitats millions of years earlier than larger mammals. In this study I examined fossil localities throughout the last 37 Ma across North America. Diversity of rodents and lagomorphs were analyzed through this time period, with examination of community structure characterized by relative percentages of taxa with different crown heights. Overall, a decrease in precipitation and temperature was found across North America from 37 …


Self-Organized Structures: Modeling Polistes Dominula Nest Construction With Simple Rules, Matthew Harrison May 2018

Self-Organized Structures: Modeling Polistes Dominula Nest Construction With Simple Rules, Matthew Harrison

Electronic Theses and Dissertations

The self-organized nest construction behaviors of European paper wasps (Polistes dominula) show potential for adoption in artificial intelligence and robotic systems where centralized control proves challenging. However, P. dominula nest construction mechanisms are not fully understood. This research investigated how nest structures stimulate P. dominula worker action at different stages of nest construction. A novel stochastic site selection model, weighted by simple rules for cell age, height, and wall count, was implemented in a three-dimensional, step-by-step nest construction simulation. The simulation was built on top of a hexagonal coordinate system to improve precision and performance. Real and idealized …


A Novel Method For Synthesis Of Hydroxytyrosol, Emmanuel Onobun Aug 2017

A Novel Method For Synthesis Of Hydroxytyrosol, Emmanuel Onobun

Electronic Theses and Dissertations

Hydroxytyrosol, 3,4-dihydroxyphenolethanol, a naturally occurring polyphenol most common in olive tree (Olea europaea), is one of the most effective member of the polyphenols family, because of its remarkable antioxidant activity, its ability to inhibit oxidation of low density lipids (LDL), and its protection against DNA oxidative damage. Hydroxytyrosol, which is widely used in cosmetics and food supplements industries, can be purchased as an olive oil extract that contains low concentration of hydroxytyrosol besides other polyphenols. The price and low natural abundance of hydroxytyrosol make alternative synthetic sources very attractive. In this research, a novel method for the synthesis of pure …


Ecological Informatics: An Agent Based Model On Coexistence Dynamics, Shiva Thapa Aug 2017

Ecological Informatics: An Agent Based Model On Coexistence Dynamics, Shiva Thapa

Electronic Theses and Dissertations

The coexistence of species is probably one of the most interesting and complex phenomenon in nature. We constructed an agent based model to study the coexistence dynamics of prey - predator populations by varying productivity levels of producers in fragmented and connected habitats along with different levels of quality of predators. Our results indicated that productivity levels of producers in fragmented and connected habitats along with levels of predator quality are significantly responsible for overall predator - prey population size and survivorship. In the absence of predation, competition between identical prey populations is more probable in connected habitats than in …


Denoising Tandem Mass Spectrometry Data, Felix Offei May 2017

Denoising Tandem Mass Spectrometry Data, Felix Offei

Electronic Theses and Dissertations

Protein identification using tandem mass spectrometry (MS/MS) has proven to be an effective way to identify proteins in a biological sample. An observed spectrum is constructed from the data produced by the tandem mass spectrometer. A protein can be identified if the observed spectrum aligns with the theoretical spectrum. However, data generated by the tandem mass spectrometer are affected by errors thus making protein identification challenging in the field of proteomics. Some of these errors include wrong calibration of the instrument, instrument distortion and noise. In this thesis, we present a pre-processing method, which focuses on the removal of noisy …


Cranial Morphological Distinctiveness Between Ursus Arctos And U. Americanus, Benjamin James Hillesheim May 2017

Cranial Morphological Distinctiveness Between Ursus Arctos And U. Americanus, Benjamin James Hillesheim

Electronic Theses and Dissertations

Despite being separated by millions of years of evolution, black bears (Ursus americanus) and brown bears (Ursus arctos) can be difficult to distinguish based on skeletal and dental material alone. Complicating matters, some Late Pleistocene U. americanus are significantly larger in size than their modern relatives, obscuring the identification of the two bears. In the past, fossil bears have been identified based on differences in dental morphology or size. This study used geometric morphometrics to look at overall differences in cranial shape and used step-wise discriminant analysis to identify specific characters that distinguish cranial morphology between …


Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett May 2017

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …


Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej May 2017

Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej

Electronic Theses and Dissertations

Fossil Agamidae from Western Australia have been the subject of limited study. To aid in fossil agamid identification, Hocknull (2002) examined the maxilla and dentary of several extant species from Australia and determined diagnostic characters for various species groups. In the study here, fossil agamids from two localities in Western Australia, Hastings Cave and Horseshoe Cave, were examined, grouped, and identified to the lowest unambiguous taxonomic level. Morphometric analyses were conducted to compare morphotypes, and find additional diagnostic characters. From Hastings Cave there were two maxilla morphotypes and three dentary morphotypes. Based on identifications, taxa present at this locality were …


Description Of Cranial Elements And Ontogenetic Change Within Tropidolaemus Wagleri (Serpentes: Crotalinae)., Nicolette L. Hill May 2016

Description Of Cranial Elements And Ontogenetic Change Within Tropidolaemus Wagleri (Serpentes: Crotalinae)., Nicolette L. Hill

Electronic Theses and Dissertations

Tropidolaemus wagleri is a species of Asian pitviper with a geographic range including Thailand, Vietnam, Malaysia, Singapore, Bruniei, parts of Indonesia, and the hilippines. Tropidolaemus is a member of the Crotalinae subfamily, within Viperidae. The genus Tropidolaemus includes five species, and was once included within the genus Trimeresurus. While some osteologic characteristics have been noted a comprehensive description of cranial elements has not been produced for T. wagleri. An in-depth description of the cranial skeleton of Tropidolaemus wagleri lays the foundation for future projects to compare and contrast other taxa within Crotalinae and Viperidae. The chosen reference specimen …


A Hierarchical Graph For Nucleotide Binding Domain 2, Samuel Kakraba May 2015

A Hierarchical Graph For Nucleotide Binding Domain 2, Samuel Kakraba

Electronic Theses and Dissertations

One of the most prevalent inherited diseases is cystic fibrosis. This disease is caused by a mutation in a membrane protein, the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is known to function as a chloride channel that regulates the viscosity of mucus that lines the ducts of a number of organs. Generally, most of the prevalent mutations of CFTR are located in one of two nucleotide binding domains, namely, the nucleotide binding domain 1 (NBD1). However, some mutations in nucleotide binding domain 2 (NBD2) can equally cause cystic fibrosis. In this work, a hierarchical graph is built for NBD2. …


Non-Anguimorph Lizards Of The Late Oligocene And Early Miocene Of Florida And Implications For The Reorganization Of The North American Herpetofauna, Kevin Chovanec May 2014

Non-Anguimorph Lizards Of The Late Oligocene And Early Miocene Of Florida And Implications For The Reorganization Of The North American Herpetofauna, Kevin Chovanec

Electronic Theses and Dissertations

Paleokarst deposits from the Oligo-Miocene of northern Florida preserve undescribed herpetofaunal remains that fill important temporal and geographic gaps in our understanding of Cenozoic lizard evolution. Here I describe and discuss the non-anguimorph lizard diversity of the Brooksville 2 (Ar2) and Miller (He1) local faunas to test for patterns of regional and latitudinal provincialism in the contemporary North American record. Collectively, the sites are significant for documenting 1) extralimital occurrences of the tropical clades Anolis and Corytophaninae, 2) a substantial temporal range extension of the modern southeastern endemic Rhineuridae, 3) the earliest record of eublepharid gekkotans from North America, and …


Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr May 2014

Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr

Electronic Theses and Dissertations

The future of Lake Baikal’s biodiversity is uncertain in response to climate change. Unlike its diverse benthos, Lake Baikal’s zooplankton is species poor, with up to 96% of its biomass being composed of a single Calanoid copepod species, Epischura baikalensis. This study characterizes the genetic differentiation and differential gene expression of E. baikalensis. Using partial-transcriptome sequences obtained by 454 Rosche and Illumina sequencing technologies, the genetic differentiation at inferred single nucleotide polymorphism (SNP) sites and differential gene expression in populations sampled from various parts of the lake were analyzed. The functional genomics of genes showed significant differential …


A Glyptosaurine Lizard From The Eocene (Late Uintan) Of San Diego, California, And Implications For Glyptosaurine Evolution And Biogeography, David Moscato Aug 2013

A Glyptosaurine Lizard From The Eocene (Late Uintan) Of San Diego, California, And Implications For Glyptosaurine Evolution And Biogeography, David Moscato

Electronic Theses and Dissertations

Glyptosaurinae is an extinct subfamily of lizards of the family Anguidae. Glyptosaurine lizards are known exclusively from the Paleogene of North America and Eurasia, reaching their peak of diversity and distribution in the Eocene. In North America these lizards are largely restricted to the intermontane basins along the Rocky Mountain range, with only sparse, indeterminately-identified skeletal elements known from outside of this region. Glyptosaurine lizards are split into two tribes: the monophyletic Glyptosaurini and paraphyletic “Melanosaurini”. Within Glyptosaurini, the most common and widespread genus is Glyptosaurus. In this study I describe a new specimen assignable to G. sylvestris, …


Systematics, Climate, And Ecology Of Fossil And Extant Nyssa (Nyssaceae, Cornales) And Implications Of Nyssa Grayensis Sp. Nov. From The Gray Fossil Site, Northeast Tennessee, Nathan R. Noll Aug 2013

Systematics, Climate, And Ecology Of Fossil And Extant Nyssa (Nyssaceae, Cornales) And Implications Of Nyssa Grayensis Sp. Nov. From The Gray Fossil Site, Northeast Tennessee, Nathan R. Noll

Electronic Theses and Dissertations

The Late Hemphillian (latest Miocene or earliest Pliocene, 7-4.5 Ma) Gray Fossil Site in northeastern Tennessee is interpreted to represent a lacustrine paleokarst fed by a river or stream. This research focuses on the morphological and systematic relations of Nyssa endocarps (fruit pits) from the fossil site to extinct and extant Nyssa species. A combination of metric and nonmetric traits allows recognition of a new species: Nyssa grayensis sp. nov. This fossil species shares the most similarities with the extant Nyssa ogeche Bartram ex Marshall from southeast North America and the Eocene fossil Nyssa eolignitica Berry from western Tennessee. Affinities …


A Mathematical Model For Antibiotic Resistance In A Hospital Setting With A Varying Population, Edward H. Snyder May 2013

A Mathematical Model For Antibiotic Resistance In A Hospital Setting With A Varying Population, Edward H. Snyder

Electronic Theses and Dissertations

Antibiotic-resistant bacteria(ARB) is causing increased health risk and cost to society. Mathematical models have been developed to study the transmission of resistant bacteria and the efficacy of preventive measures to slow its spread within a hospital setting. The majority of these models have assumed a constant total hospital population with the admission and discharge rates being equal throughout the duration. But a typical hospital population varies from day to day and season to season. In this thesis, we apply variable admission and discharge daily rates to existing deterministic and stochastic models which examine the transmission of single and dual resistant …


A Predictive Model Which Uses Descriptors Of Rna Secondary Structures Derived From Graph Theory., Alissa Ann Rockney May 2011

A Predictive Model Which Uses Descriptors Of Rna Secondary Structures Derived From Graph Theory., Alissa Ann Rockney

Electronic Theses and Dissertations

The secondary structures of ribonucleic acid (RNA) have been successfully modeled with graph-theoretic structures. Often, simple graphs are used to represent secondary RNA structures; however, in this research, a multigraph representation of RNA is used, in which vertices represent stems and edges represent the internal motifs. Any type of RNA secondary structure may be represented by a graph in this manner. We define novel graphical invariants to quantify the multigraphs and obtain characteristic descriptors of the secondary structures. These descriptors are used to train an artificial neural network (ANN) to recognize the characteristics of secondary RNA structure. Using the ANN, …


Determination Of Cholesterol In Foods By Flow Injection Analysis With Perroxyoxalate Chemiluminescence., Abisake Feleke Aug 2006

Determination Of Cholesterol In Foods By Flow Injection Analysis With Perroxyoxalate Chemiluminescence., Abisake Feleke

Electronic Theses and Dissertations

Cholesterol is an important biological molecule with many important functions. However, high serum cholesterol is a health hazard. Thus analysis of cholesterol is important and many analytical techniques have been developed. The objectives of the proposed research are to develop an economical, rapid method for the determination of total cholesterol with good selectivity and enhanced sensitivity. For evaluation of proposed flow injection analysis with peroxyoxalate chemiluminescence (FIA-POCL) method, figures of merit such as accuracy, precision, and linear dynamic range will be assessed. The proposed procedure was then applied to the determination of total cholesterol in foods. The procedure was linear …


Using Domination To Analyze Rna Structures., Travis Reves Coake May 2005

Using Domination To Analyze Rna Structures., Travis Reves Coake

Electronic Theses and Dissertations

Understanding RNA molecules is important to genomics research. Recently researchers at the Courant Institute of Mathematical Sciences used graph theory to model RNA molecules and provided a database of trees representing possible secondary RNA structures. In this thesis we use domination parameters to predict which trees are more likely to exist in nature as RNA structures. This approach appears to have promise in graph theory applications in genomics research.


A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane Dec 1993

A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane

Electronic Theses and Dissertations

Extraction of the lipids of Legionella pneumophila yields phases unlike those produced from other Gram-negative bacteria. A viscous interface forms between the aqueous (wash) and organic phases. More than half of the hydroxylated fatty acids were found distributed between the aqueous phase and the interfacial material, fractions in which such constituents have not been reported in other Gram-negative species. It was further observed that after the material from the aqueous/interfacial phase was dissolved in methanol or chloroform/methanol (2:1 (V/V)), the addition of acetone would create a white, flocculent precipitate. Analyses showed that the supernatant contained fatty acids that were nonhydroxylated …