Pathogenic Microbiology Commons^™

Identification And Molecular Characterisation Of Mycobacteriophages And Their Lysis Proteins, Marine Henry

Theses

Given their potential as specific and natural biocontrol agents, bacteriophages and their associated proteins have become the focus of renewed interest over the last decade. This study reviews the current state of mycobacterial diseases control worldwide and presents how phage therapy and the production of recombinant bacteriophage lysis proteins can be applied as novel biocontrol strategies for mycobacteria.

Chapter 11 presents an overview of the predicted LysA and LysB proteins in all the mycobacteriophages sequenced to date and proposes an in silico 3D predictive model of the lysin B of a recently isolated and characterised mycobacteriophage. Our data also confirms …

The Rapid Identification Of Novel Anti-Mycobacterial Drugs And The Transporters Involved In Their Resistance, James Carroll

Theses

Despite the success of anti-mycobacterial drugs over the past 70 years, mycobacterial disease, particularly tuberculosis is still responsible for millions of deaths worldwide. Additionally, the emergence of Multidrug Resistant (MDR-TB) and Extensively Drug Resistant (XDR-TB) Tuberculosis throughout the world has motivated calls by the World Health Organization for novel mycobacterial drugs, vaccines and diagnostic tests. Consequently, this study sought to identify and evaluate the efficacy of a range of anti-mycobacterial compounds against a representative cohort of pathogenic mycobacterial species. The development and employment of the rapid, robust and inexpensive microtitre alamarBlue assay (MABA) facilitated the assessment of a vast array …

Isolation And Molecular Characterization Of Mycobacterium Avium Subsp. Paratuberculosis In Ireland, Pierre Emmanuel Douarre

Theses

MAP is a proven animal pathogen causing Johne's disease, one of the most widespread and economically important diseases of ruminants. Since 1992 and the opening of the European market, the prevalence of MAP in Ireland has increased considerably. Improvements in diagnostic strategies for Ireland and elsewhere are urgently required. MAP infects a wide host range and has emerged as a potential threat to human health and has been associated with Crohn's disease. The control of paratuberculosis infection requires a better understanding of the genetic diversity of the pathogen. The objective of this study was to isolate and characterize this enteric …

Enhancement Of The Antibacterial Properties Of Silver Nanoparticles Using Beta-Cyclodextrin As A Capping Agent, Swarna Jaiswal, Brendan Duffy, Niall Stobie, Patrick Mchale, Amit Jaiswal

Articles

Silver nanoparticles (AgNPs) were synthesized by reducing silver salts using NaBH4 followed by capping with varying concentrations of β-cyclodextrin (β-CD) and were physically characterised. Antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was determined by a microtitre well method. The AgNPs were spherical under TEM while DLS showed average diameters of capped particles to be smaller (4-7 nm) than their uncapped equivalents (17 nm). Capped particles demonstrated superior photostability when exposed to intense UV radiation for 4 hours and a significantly (p

Enterobacterial Repetitive Intergenic Consensus-Pcr (Eric-Pcr) Analysis Among Raw Vegetables Isolates Of Campylobacter Jejuni., Tuan Suraya Tuan Soh

Student Works (2010-2019)

A total of 20 (n=20) raw vegetable isolates of Campylobacter jejuni were examined for the presence of virulence genes and genetic diversity using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) analysis. All C. jejuni isolates were obtained from the laboratory of Food Science and Biotechnology, University Putra Malaysia, Serdang, Selangor. When specific PCR amplification were determined, all raw vegetables isolates of Campylobacter jejuni contained cadF and ceuE genes. Whereas, 12 (12/20) isolates were positive cdtB and 6 (6/20) were positive cdtC. None of the C. jejuni isolates was cdtA positive. Using ERIC-PCR analysis, all 20 isolates of C. jejuni were …

Phage Lysins - Structure, Genetics And Applications, Jennifer Garry

Theses

Antibiotics are of the utmost importance in the fight against pathogenic bacteria, however, in recent years there has been a continual increase in the development of antibiotic resistance among bacteria. As a result it has become essential to develop new technologies to combat these pathogens. One such technology is the application of phage lysins as antimicrobial agents against pathogenic infections. A promising phage lysin is LysK, a 495 amino-acid protein derived from Staphylococcal Phage K. LysK can lyse a wide range of staphylococcal species including MRSA. It is also capable of killing both live and dead cells increasing its potential …

Pattern Recognition In Cytopathology For Papanicolaou Screening, Jonathan Blackledge, Dmitriy Dubovitskiy

Conference papers

A unique space oriented filer is presented in order to detect and isolate the cell of a nucleus for applications in cytopathology. A classification method for nuclei is then considered based on the application of a set of features which includes certain fractal parameters. Segmentation algorithms are considered in which a self-adjustable sharpening filter is designed to enhance object location. Although the methods discussed and the algorithms developed have a range of applications, in this work we focus the engineering of a system for automating a Papanicolaou screening test using standard optical images

Evolutionary Aspects Of Urea Utilization By Fungi, Dhammika H. M. L. P Navarathna, Steven D. Harris, David D. Roberts, Kenneth W. Nickerson

Kenneth Nickerson Papers

The higher fungi exhibit a dichotomy with regard to urea utilization. The hemiascomycetes use urea amidolyase (DUR1,2), whereas all other higher fungi use the nickel-containing urease. Urea amidolyase is an energy-dependent biotincontaining enzyme. It likely arose before the Euascomycete/Hemiascomycete divergence c. 350 million years ago by insertion of an unknown gene into one copy of a duplicated methylcrotonyl CoA carboxylase (MccA). The dichotomy between urease and urea amidolyase coincides precisely with that for the Ni/Co transporter (Nic1p), which is present in the higher fungi that use urease and is absent in those that do not. We suggest that …

Candida Albicans Cellwall Components And Farnesol Stimulate The Expression Of Both Inflammatory And Regulatory Cytokines In The Murine Raw264.7 Macrophage Cell Line, Suman Ghosh, Nina Howe, Katie Volk, Swetha Tati, Kenneth W. Nickerson, Thomas M. Petro

Kenneth Nickerson Papers

Candida albicans causes candidiasis, secretes farnesol, and switches from yeast to hyphae to escape from macrophages after phagocytosis. However, before escape, macrophages may respond to C. albicans’ pathogen-associated molecular patterns (PAMPs) through toll-like receptor 2 (TLR2) and dectin-1 receptors by expressing cytokines involved in adaptive immunity, inflammation, and immune regulation. Therefore, macrophages and the RAW264.7 macrophage line were challenged with C. albicans preparations of live wild-type cells, heat-killed cells, a live mutant defective in hyphae formation, a live mutant producing less farnesol, or an isolate producing farnesoic acid instead of farnesol. Interleukin-6 (IL-6), and IL-1b, IL- 10, and tumor …

Killing Of Treponema Denticola By Mouse Peritoneal Macrophages, P. Gaibani, C. Vocale, S. Ambretti, F. Cavrini, Jacques Izard, L. Miragliotta, M. T. Pellegrino, V. Sambri

Department of Food Science and Technology: Faculty Publications

Treponema denticola has been identified as an important cause of periodontal disease and hypothesized to be involved in extra-oral infections. The objective of this study was to investigate the role of T. denticola cell length and motility during mouse peritoneal macrophages in vitro uptake. Macrophages, incubated under aerobic and anaerobic conditions, produced a similar amount of TNF-α when stimulated with Escherichia coli LPS. The uptake of FlgE- and CfpA-deficient mutants of T. denticola was significantly increased compared with the wild-type strain, due to cell size or lack of motility. Opsonization with specific antibodies considerably improved the treponemes’ uptake. …

Preface To Special Issue

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

The Regulation Of The Icsp Promoter Of Shigella Flexneri By Ryhb, Lia A. Africa, Helen J. Wing

Undergraduate Research Opportunities Program (UROP)

Iron is an essential element in the metabolism of many organisms, including bacteria. In many pathogenic bacteria, the levels of iron present trigger the expression of many virulence genes. In Shigella, a gram-negative bacterium that causes dysentery in humans, the expression of a small regulatory RNA, ryhB, is blocked in the presence of iron. Studies have revealed that ryhB represses virB, a global regulator of virulence genes in Shigella.

The icsP gene is under the direct control of VirB. icsP encodes an outer membrane protease that cleaves a protein necessary for the actin tail assembly of Shigella in vitro. In …

Cloning And Expression Of A Putative Exported Protein Coding Gene Sas1089 From An Invasive Community Associated Staphylococcus Aureus Strain Mssa476, Nailah Alzaki

All-Inclusive List of Electronic Theses and Dissertations

Originally, methicillin resistant Staphylococcus aureus (MRSA) occurred primarily in the hospital setting and was designated hospital- associated MRSA (HA-MRSA). In recent years, isolates of Staphylococcus aureus from the community (CA-MRSA), found to be methicillin resistant, are not as resistant tooth~ antibiotics as HA-MRSA. However, community strains are noted for their invasiveness causing soft tissue infections with propensity for invasion to deeper sites.

Escherichia Coli O157:H7 And Other E. Coli Strains Share Physiological Properties Associated With Intestinal Colonization, Lisa Jacobsen, Lisa Durso, Tyrell Conway, Kenneth W. Nickerson

Kenneth Nickerson Papers

Escherichia coli isolates (72 commensal and 10 O157:H7 isolates) were compared with regard to physiological and growth parameters related to their ability to survive and persist in the gastrointestinal tract and found to be similar. We propose that nonhuman hosts in E. coli O157:H7 strains function similarly to other E. coli strains in regard to attributes relevant to gastrointestinal colonization.

Native Cellular Architecture Of Treponema Denticola Revealed By Cryo-Electron Tomography, Jacques Izard, Chyong-Ere Hsieh, Ronald J. Limberger, Carmen A. Mannella, Michael Marko

Department of Food Science and Technology: Faculty Publications

Using cryo-electron tomography, we are developing a refined description of native cellular structures in the pathogenic spirochete Treponema denticola. Tightly organized bundles of periplasmic flagella were readily observed in intact plunge-frozen cells. The periplasmic space was measured in both wild-type and aflagellate strains, and found to widen by less than the diameter of flagella when the latter are present. This suggests that a structural change occurs in the peptidoglycan layer to accommodate the presence of the flagella. In dividing cells, the flagellar filaments were found to bridge the cytoplasmic cylinder constriction site. Cytoplasmic filaments, adjacent to the inner membrane, …

An Evaluation Of Methicillin Resistant Staphylococcus Aureus Survival On Five Environmental Surfaces Under Two Different Humidities, With And Without The Addition Of Bovine Serum Albumin, Courtney Ann Coughenour

UNLV Theses, Dissertations, Professional Papers, and Capstones

The spread of antibiotic resistant bacteria is a major public health concern, as they result in greater healthcare costs and increased morbidity and mortality rates. Methicillin resistant Staphylococcus aureus (MRSA) is one organism of particular concern, with the number of infections increasing in epidemic proportion. Bacterial surface contamination with MRSA is significant, as it may serve as a reservoir for transmission and have negative health implications. The purpose of this study was to evaluate survival of MRSA on five environmental surface materials; glass, wood, vinyl, plastic, and cloth. The effect of relative humidity (RH) and bovine serum albumin (BSA) were …

Effects Of The Pathogenic Water Mold Saprolegnia Ferax On Survival Of Amphibian Larvae, John M. Romansic, Kristin A. Diez, Elise M. Higashi, James E. Johnson, Andrew R. Blaustein

All Faculty Scholarship for the College of the Sciences

Infectious diseases are a significant threat to worldwide biodiversity. Amphibian declines, a significant part of current biodiversity losses, are in many cases associated with infectious disease. Water molds are one group of pathogens affecting amphibians on a worldwide basis. Although water molds have been studied extensively for their effects on host embryos, little information is available about how they affect post-embryonic amphibians. We tested the effects of one species of water mold, Saprolegnia ferax, in a comparative study of larvae of 4 amphibian species: Pseudacris regilla (Pacific treefrog), Rana cascadae (Cascades frog), Ambystoma macrodactylum (long-toed salamander), and R. aurora (red-legged …

An Essay On Evolution: Evolution And The Origin Of Life Are Separate And Distinct Concepts, Kenneth Nickerson

Kenneth Nickerson Papers

Two years ago on a Saturday morning, I was asked quite pointedly by two friends how I could be both spiritual and a scientist. My questioning friends felt that these qualities were incompatible. It turned out their church taught that scientists were ‘the enemy’ because scientists believe in evolution. Since that time, Letters to the Editor regarding evolution have attracted my attention. Many of the published letters stated that the author did not believe in evolution, and argued in support of his/her position that God had created life. The authors thoroughly confuse two concepts which are separate and distinct: Evolution …

Host And Seasonal Effects On The Infection Dynamics Of Skrjabinoptera Phrynosoma (Ortlepp) Schulz, 1927, A Parasitic Nematode Of Horned Lizards, Kathryn Claire Hilsinger

College of Graduate Studies: Theses & Dissertations

Author's Abstract: Skrjabinoptera phrynosoma (Ortlepp) Schulz, 1927 is a common parasitic nematode of horned lizards. The life cycle of S. phrynosoma was described by Lee in 1957, but has received little attention since. The present study addressed effect of season as well as host characteristics on the infection dynamics in lizard hosts. In the Alvord Basin in southeastern Oregon, S. phrynosoma were collected from Phrynosoma platyrhinos Gerard 1852 horned lizards via stomach flushes, cloaca flushes and fecal pellet collections. Parasite load variables (number of nematodes per host, length of those nematodes, and total worm burden (ΣL)) were analyzed within three …

Letter From The Dean, Lalit Verma

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Development Of Pcr Assays To Detect And Characterise Salmonella Isolates From Cheese And Meat Products By Utilizing An Integrated Genomics Approach, Noelle Geraldine Mccarthy

Theses

Salmonella is an extremely important foodborne pathogen which is responsible for millions of cases of gastroenteritis annually. Salmonella outbreaks have been associated with numerous common food stuffs such as meat, dairy and seafood. Traditional culture based methods for the detection Salmonella are labourious and costly. Rapid detection and serovar identification would dramatically decrease the time required to identify Salmonella outbreaks and potential health risks.

In the US 99% of all Salmonella infections are caused by members of Salmonella enterica subspecies 1. Serovars within subspecies 1 can vary due to host specificity and pathogenicity. DNA sequencing projects have provided valuable genomic …

Pyramidobacter Piscolens Gen. Nov., Sp. Nov., A Member Of The Phylum ‘Synergistetes’ Isolated From The Human Oral Cavity, Julia Downes, Sonia R. Vartoukian, Floyd E. Dewhirst, Jacques Izard, Tsute Chen, Wen-Han Yu, Iain C. Sutcliffe, William G. Wade

Department of Food Science and Technology: Faculty Publications

Four strains of anaerobic, gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group distinct from any species with validly published names. 16S rRNA and 23S rRNA gene sequence analyses and DNA–DNA reassociation data revealed that the strains constituted a novel group within the phylum ‘Synergistetes’ and were most closely related to Jonquetella anthropi. Two libraries of randomly cloned DNA were prepared from strain W5455T and were sequenced to provide a genome survey as a resource for metagenomic studies. A new genus …

Cryo-Electron Tomography Elucidates The Molecular Architecture Of Treponema Pallidum, The Syphilis Spirochete, Jacques Izard, Christian Renken, Chyong-Ere Hsieh, Daniel C. Desrosiers, Star Dunham-Ems, Carson La Vake, Linda L. Gebhardt, Ronald J. Limberger, David L. Cox, Michael Marko, Justin D. Radolf

Department of Food Science and Technology: Faculty Publications

Cryo-electron tomography (CET) was used to examine the native cellular organization of Treponema pallidum, the syphilis spirochete. T. pallidum cells appeared to form flat waves, did not contain an outer coat and, except for bulges over the basal bodies and widening in the vicinity of flagellar filaments, displayed a uniform periplasmic space. Although the outer membrane (OM) generally was smooth in contour, OM extrusions and blebs frequently were observed, highlighting the structure’s fluidity and lack of attachment to underlying periplasmic constituents. Cytoplasmic filaments converged from their attachment points opposite the basal bodies to form arrays that ran roughly …

Microbiology Of Oil Fly Larvae, Kenneth Nickerson, Bradley A. Plantz

Kenneth Nickerson Papers

One animal beautifully adapted to the viscous asphalt of the La Brea tar pits is the oil fly Helaeomyia petrolei (Syn. Psilopa). As a normal part of its carnivorous existence the oil fly larval guts are filled with tar, with no adverse effects. Surface sterilized larvae 5 contained ca. 2 x 10 heterotrophic bacteria per larva. These bacteria have been identified as a mixture of enteric bacteria, most commonly Providencia rettgeri, and Acinetobacter spp. These bacteria were clearly growing because their numbers in the larval guts were 100 to 1,000 times greater than in free oil/asphalt. There is …

Herpes Simplex Virus Glycoprotein D/Host Cell Surface Interaction Stimulates Chlamydia Trachomatis Persistence Via A Novel Pathway., Jennifer Vanover

Electronic Theses and Dissertations

When presented with certain unfavorable environmental conditions, C. trachomatis reticulate bodies (RBs) enter into a viable, yet noncultivable state called persistence. Two hallmarks of persistent chlamydiae are swollen, aberrantly shaped RBs, as viewed by transmission electron microscopy and a decrease in infectious progeny. Several models of chlamydial persistence have been described, including interferon-γ (IFN-γ), IFN-α, IFN-β, and tumor necrosis factor-α-exposure and nutrient deprivation. Previously, we established an in vitro co-infection model of two of the most common sexually transmitted pathogens in the United States, C. trachomatis and Herpes Simplex Virus-2 (HSV). Data from this tissue culture model indicate that: i) …

Modulation Of The Nf-Κb Pathway By Bordetella Pertussis Filamentous Hemagglutinin, Tzvia Abramson, Hassya Kedem, David A. Relman

Faculty Publications, Biological Sciences

Background
Filamentous hemagglutinin (FHA) is a cell-associated and secreted adhesin produced by Bordetella pertussis with pro-apoptotic and pro-inflammatory activity in host cells. Given the importance of the NF-κB transcription factor family in these host cell responses, we examined the effect of FHA on NF-κB activation in macrophages and bronchial epithelial cells, both of which are relevant cell types during natural infection.

Methodology/Principal Findings
Exposure to FHA of primary human monocytes and transformed U-937 macrophages, but not BEAS-2B epithelial cells, resulted in early activation of the NF-κB pathway, as manifested by the degradation of cytosolic IκBα, by NF-κB DNA binding, and …

A New Species Of Genus Laboulbenia (Laboulbeniales) On Craspedophorus Formosanus (Coleoptera, Carabidae) From Taiwan, With A Note On Laboulbenia Asiatica, Katsuyuki Terada, Meng-Hao Hsu, Wen-Jer Wu

Aliso: A Journal of Systematic and Floristic Botany

Laboulbenia taiwaniana sp. nov. on Craspedophorus formosanus is described from Taiwan and illustrated with photographs. It is characterized by a long, asymmetrical perithecium with an oblique apex and a pale-colored lower wall, a slender, evenly tapered receptacle with cylindrical cell I and II and trapezoidal cell IV, well developed appendages with black septa concentrated in the basal portion of the appendage system, and especially by black septa on the distal end of cell g. Laboulbenia asiatica, which was described from an Asian carabid---"Casnonia sp."---in 1899 and was illustrated in 1908 by Thaxter, is reviewed and compared …

Laboulbeniales On Semiaquatic Heteroptera. A New Species Of Triceromyces (Ascomycota, Laboulbeniales) On Microvelia (Heteroptera, Veliidae) From Spain, Sergio Santamaria

Aliso: A Journal of Systematic and Floristic Botany

A new species of fungal genus Triceromyces (Laboulbeniales) is described: Triceromyces benjaminii. The description is based on several thalli found on the insect host Microvelia pygmaea (Heteroptera, Veliidae), collected in two localities from SE Spain. Characteristics of male and female thalli of this dioecious species are discussed and compared with other dioecious taxa. The characteristics of male thalli require some adjustment in generic limits. This is the first species of Triceromyces known to parasitize a species of Microvelia, a semiaquatic heteropteran genus. The new species is described and illustrated with line drawings and photographs. A table collates information …

The Genus Prolixandromyces (Laboulbeniales) In The Old World Prolixandromyces (Laboulbeniales), Alex Weir

Aliso: A Journal of Systematic and Floristic Botany

Two new species of Prolixandromyces (Laboulbeniales) parasitic on Rhagovelia (Heteroptera: Veliidae) are described and illustrated: Prolixandromyces benjaminii from the Philippine Islands and P. lanceolatus from Africa (Madagascar, Malawi, Nigeria, Sierra Leone, and South Africa) and Asia (Indonesia: Sulawesi, Sumba, Timor; Malaysia: Selangor; and Sri Lanka). In order to accommodate these species the circumscription of Prolixandromyces is emended. The new taxa are compared with the one known species from the Old World, P. triandrus from Spain, and with the five known New World taxa.

New Species Of Cucujomyces (Laboulbeniales) On Chilean Leiodidae, Walter Rossi, Alex Weir

Aliso: A Journal of Systematic and Floristic Botany

Four new species of Cucujomyces (Laboulbeniales) parasitic on Leiodidae (Coleoptera) from Chile are described and illustrated: Cucujomyces dasypelatis on Dasypelates nebulosus, C. gratiellae on Hydnodietus brunneus, C. neohydnobii on Neohydnobius argentinicus, and C. newtonii on Metahydnobius spp. The new taxa are compared with other known species of Cucujomyces. Morphological variation encountered in one of the new species, C. gratiellae, encompasses attributes of both Cucujomyces and Balazucia, necessitating Balazucia to be placed in synonymy under Cucujomyces. On the basis of this, two new combinations, Cucujomyces bilateralis and C. japonicus, are proposed.