Microbiology Commons^™

Biosolar Conversion Of N2 And H2o To Ammonia By Engineered N2-Fixing Cyanobacteria, Seth T. Harris

The Journal of Undergraduate Research

The cyanobacterium Anabaena sp. PCC 7120 is capable of using solar energy to produce ammonia through conversion of atmospheric dinitrogen in differentiated cells called heterocysts. Harnessing this system could enable cyanobacteria to be used in ammoniafertilizer production, creating a renewable alternative to the current Haber-Bosch process. The genes patA and alr3304 in the Anabaena 7120 genome are important in heterocyst formation; an increase in heterocyst formation is seen with over-expression of patA or inactivation of alr3304. This research aims to create a novel mutant that forms more heterocysts by simultaneously over-expressing patA and inactivating alr3304, producing higher amounts of ammonia. …

Laser-Induced Breakdown Spectroscopy (Libs): An Innovative Tool For Studying Bacteria, Qassem I. Mohaidat

Wayne State University Dissertations

Laser-induced breakdown spectroscopy (LIBS) has gained a reputation as a flexible and convenient technique for rapidly determining the elemental composition of samples with minimal or no sample preparation. In this dissertation, I will describe the benefits of using LIBS for the rapid discrimination and identification of bacteria (both pathogenic and non-pathogenic) based on the relative concentration of trace inorganic elements such as Mg, P, Ca, and Na. The speed, portability, and robustness of the technique suggest that LIBS may be applicable as a rapid point-of-care medical diagnostic technology.

LIBS spectra of multiple genera of bacteria such as Escherichia, Streptococcus, Mycobacterium, …

Evaluation Of A Biopesticide Against Invasive Species For Native Species Restoration, Denise Ann Mayer

Legacy Theses & Dissertations (2009 - 2024)

Since their introduction in the 1980s, dreissenid mussels (Dreissena polymorpha and D. rostriformis bugensis) rapidly spread throughout North America and have had severe impacts on the ecology of freshwater ecosystems. A project was initiated in the early 1990s at the New York State Museum's Field Research Laboratory to discover and develop natural products to control industrial biofouling by dreissenid mussels. A strain of Pseudomonas fluorescens (Pf-CL145A), isolated from the sediment of a North American river, was found to be effective at killing dreissenids. The strain was patented for this use.

Herpes Simplex Virus Type 1 : Interactions With The Cellular Proteasome And Microrna Pathways, Daniel Joseph Munson

Legacy Theses & Dissertations (2009 - 2024)

Herpes Simplex Virus Type 1 (HSV-1) is a human pathogen that is estimated to have infected 60-80% of the population worldwide, causing oral lesions, encephalitis, and blindness. Infection results in life-long latency of the virus, with periods of reactivation and symptomatic disease. Early in infection, HSV-1 induces the formation of replication compartments and VICE (virus induced chaperone enriched) domains within the nucleus. Adjacent to VICE domains, we observed foci which contained Mss1, a cellular protein normally associated with the proteasome. Mss1 belongs to the AAA-ATPase family of proteins, which have been shown to function in DNA repair, transcription, translation, and …

Banf1 Is Required To Maintain The Self-Renewal Of Both Mouse And Human Embryonic Stem Cells, Jesse L. Cox, Sunil K. Mallanna, Briana D. Ormsbee, Michelle Desler, Matthew S. Wiebe, Angie Rizzino

Nebraska Center for Virology: Faculty Publications

Self-renewal is a complex biological process necessary for maintaining the pluripotency of embryonic stem cells (ESCs). Recent studies have used global proteomic techniques to identify proteins that associate with the master regulators Oct4, Nanog, and Sox2 in ESCs or in ESCs during the early stages of differentiation. Through an unbiased proteomic screen, Banf1 was identified as a Sox2- associated protein. Banf1 has been shown to be essential for worm and fly development but, until now, its role in mammalian development and ESCs has not been explored. In this study, we examined the effect of knocking down Banf1 on ESCs. We …

Analysis Of The Streptococcal Cpsa Protein In Dna-Binding And Regulation Of Capsule And Cell Wall Maintenance, Brett R. Hanson

Wayne State University Dissertations

The systemic pathogens Streptococcus agalactiae (GBS) and Streptococcus pneumoniae remain a significant threat to human health worldwide. The ability of these organisms to cause systemic disease is compounded by the production of a polysaccharide capsule that provides immune evasion function. The production of the polysaccharide capsule in systemic streptococcal pathogens is controlled in part by the membrane bound protein CpsA. These studies analyze the contribution of CpsA to regulation of capsule level in the model aquatic pathogen Streptococcus iniae and human specific pathogen GBS, and how this regulation affects virulence in in-vitro, ex-vivo, and in-vivo models of pathogenesis. We have …

Characterisation Of Bacterial Extracellular Polysaccharides (Eps) And Other Complex Carbohydrates With Prebiotic Potential, Padraigin Murphy

Theses

Prebiotics are selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microbiota that confers benefits upon host well-being and health’ It is not the prebiotic by itself but rather the changes induced in microflora composition that is responsible for its effects. Several sources of prebiotic were used in this study, namely extracellular polysaccharides (EPS) originating from Lactic Acid Bacteria (LAB), barley, oat. Laminaria digitata. Laminaria hyperborea and Saccharomyces cerevisiae. EPS-producing LAB were isolated from a wide variety of environmental and gastrointestinal niches. The strains were typed and classified according to their EPS-producing ability …

Surface Entropy Reduction To Increase The Crystallizability Of The Fab-Rna Complex, Priyadarshini Palaniandy Ravindran

Electronic Theses and Dissertations

Crystallizing RNA has been an imperative facet and a challenging task in the world of RNA research. Assistive methods such as Chaperone Assisted RNA Crystallography (CARC), employing monoclonal antibody fragments (Fabs) as crystallization chaperones have enabled us to obtain RNA crystal structures by increasing the crystal contacts and providing initial phasing information. Using this technology the crystal structure of [delta]C209 P4-P6 RNA (an independent folding domain of the self-splicing Tetrahymena group I intron) complexed to Fab2 (high affinity binding Fab) has been resolved to 1.95 Å (1). Although the complexed class I ligase ribozyme has also been crystallized using CARC …

Enhanced Surveillance And Characterisation Of Three Significant Gram-Positive Pathogens, Annmarie Mollaghan

Theses

Clinical microbiology has been revolutionised in recent years by the introduction of molecular biology. Traditionally, the gold standard for diagnosis in the clinical microbiology laboratory has been culture, which in some cases, is gradually being replaced by molecular detection methods, particularly where the pathogen is difficult to grow or to identify, or when the significance of an organism is dependent on the detection of specific markers of pathogenicity, such as toxins. Many fastidious bacteria which are difficult to culture and present public health implications, i.e. Mycobacterium tuberculosis. Chlamydia trachomatis and Neisseria gonorrhoea, can now be detected using commercial molecular assays …

The Evolution Of Bacteriophages E11/2 And E4/Lc For Control Of Verocytotxigenic E.Coli At Key Stages In The Beef Chain, Bríd Coffey

Theses

The objective of this thesis was lo evaluate the potential of bactcriophages e4/1 c and cl 1/2 ns biocontrol agents for E. coli O157:H7. Initially, e4/lc and el 1/2 were subjected to high-throughput 454 sequencing. The data generated revealed that e4/I c (47,112 bp) is very similar to the lytic E. coli phages RTP and JK06. Interestingly, differences within the tail module led to the identification of a putative site of attachment to E. coli O157:H?. Comparative genomic analysis indicated that el 1/2 (168,470 bp) is a novel member of the T-even group, with high degrees of similarity to T4 …

A Messenger Molecule Governs Interdependency In An Evolved Pseudomonas Aeruginosa Biofilm Community, Thomas Macelliott Johnson

Honors Theses and Capstones

Biofilm populations are known to harbor great diversity, but the importance of this diversity is not fully understood. A likely contributor to this variation is the second messenger molecule cyclic-di-GMP: low levels associate with a planktonic lifestyle while high levels favor biofilm formation. In ongoing studies of an evolving biofilm population of Pseudomonas aeruginosa (PA), we observed extensive ecological diversification that may relate to this lifestyle switch. In PA, the gene bifA encodes a phosphodiesterase that is known to degrade cyclic-di-GMP and reduce biofilm. This gene was cloned onto a plasmid under control of an inducible promoter and the plasmid …

An Investigation Of The Subtype Diversity Of Clinical Isolates Of Irish Clostridium Difficile Ribotypes 027 And 078 By Repetitive-Extragenic Palindromic Pcr, Denise Drudy, K. Solomon, S. Murray, L. Scott, S. Mcdermott,, A. Martin, C. O’Donoghue, M. Skally, K. Burns, L. Fenelon, F. Fitzpatrick,, L. Kyne, S. Fanning

Articles

A repetitive-extragenic palindromic PCR (rep-PCR) subtyping method (DiversiLab) in conjunction with ribotyping, toxinotyping and antimicrobial-susceptibility testing was used to detect subtypes within Clostridium difficile ribotypes 027 and 078. Clinical isolates of ribotypes 027 (toxinotype III) (n530) and 078 (toxinotype V) (n523) were provided by health-care facilities across the Republic of Ireland over 2 months in 2006 and 1 month in 2009. Ribotype 027 isolates were significantly more related to each other (9 different subtype profiles) when compared to ribotype 078 isolates (14 different profiles) (P50.001; cut-off .90 % similarity). Almost half of ribotype 078 isolates (45.5 %) showed no relationship …

Humboldt Journal Of Microbiology: Volume 13, Number 1- May 2011, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.

Abundance Of Eukaryotic Microbes In The Deep Subtropical North Atlantic, Danielle Morgan-Smith, Gerhard J. Herndl, Hendrik M. Van Aken, Alexander B. Bochdansky

OES Faculty Publications

The meso- and bathypelagic ocean comprises the largest habitat on earth, yet we know very little about the distribution and activity of protists in this environment. These small eukaryotes are responsible for controlling bacterial abundance in the surface ocean and are major players in the material and energy transfer of pelagic food webs. In this paper, we quantify microbial eukaryotes in the deep North Atlantic, as well as provide a basic characterization of eukaryote community changes through the water column. To this end, we counted organisms using 2 different approaches: (1) catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH, also …

Human Endogenous Retrovirus Transcription Profiles Of The Kidney And Kidney-Derived Cell Lines, Sonja Haupt, Michele Tisdale, Michelle Vincendeau, Mary Anne Clements, David T. Gauthier, Raymond Lance, O. John Demmes, Adriana Tuqueti-Neves, Elfriede Noessner, Christine Leib-Mösch, Alex D. Greenwood

Biological Sciences Faculty Publications

The human genome comprises approximately 8-9% of human endogenous retroviruses (HERVs) that are transcribed with tissue specificity. However, relatively few organs have been examined in detail for individual differences in HERV transcription pattern, nor have tissue-to-cell culture comparisons been frequently performed. Using an HERV-specific DNA microarray, a core HERV transcription profile was established for the human kidney comparing 10 tissue samples. This core represents HERV groups expressed uniformly or nearly so in non-tumour kidney tissue. The profiles obtained from non-tumour tissues were compared to 10 renal tumour tissues (renal cell carcinoma, RCC) derived from the same individuals and additionally, to …

Purification, Characterisation And Applications Of A Cloned Staphylococcal Bacteriophage Lysin For The Control Of Multi-Drug Resistant Staphylococcus Aureus Including Mrsa, Mark Fenton

Theses

The work presented in this thesis focuses on the purification, characterisation and practical applications of an anti-staphylococcal lysin (LysK) and its single-domain truncated derivative (CHAP_k) against pathogenic staphylococci including meticillin resistant Staphylococcus aureus (MRSA). Both proteins were purified to greater than 90% homogeneity. Affinity chromatography was applied as the optimum method for LysK purification and ion-exchange chromatography was successfully applied to CHAP_k. The lytic spectrum of LysK was investigated by zymogram analysis where the enzyme exhibited strong activity against a range of staphylococci regardless of their origin, sequence type (ST) or antibiotic resistant profile. This analysis …

Efficacy Of The Pentavalent Rotavirus Vaccine, Rotateq (Rv5), Between Doses Of A 3-Dose Series And With Less Than 3 Doses (Incomplete Regimen), Penelope D. Dennehy, Timo Vesikari, David O. Matson, Robbin F. Itzler, Michael J. Dallas, Michelle G. Goveia, Mark J. Dinubile, Penny M. Heaton, Max Ciarlet

Community & Environmental Health Faculty Publications

Post-hoc analyses of the Rotavirus Efficacy and Safety Trial (RES T) were conducted to determine whether the pentavalent rotavirus vaccine (RV5) confers early protection against rotavirus gastroenteritis (RVGE) before completion of the 3-dose regimen. To evaluate the efficacy of RV5 between doses in reducing the rates of RVGE-related hospitalizations and emergency department (ED) visits in infants who ultimately received all 3 doses of RV5/placebo, events occurring from 2 weeks after the first and second doses to receipt of the subsequent dose (Analysis A) and events occurring from 2 weeks after the first and second doses to 2 weeks after the …

Characterization Of Photochromogenic Mycobacterium Spp. From Chesapeake Bay Striped Bass Morone Saxatilis, D. T. Gauthier, A. M. Helenthal, M. W. Rhodes, W. K. Vogelbein, H. I. Kator

Biological Sciences Faculty Publications

A large diversity of Mycobacterium spp. has been isolated from striped bass Morone saxatilis in Chesapeake Bay, USA. The new species M. shottsii and M. pseudoshottsii are the dominant isolates, while the classical fish pathogen M. marinum is found much less frequently. M. fortuitum and M. chelonae, other Mycobacterium spp. known to commonly infect fishes, have not yet been aseptically isolated from striped bass within Chesapeake Bay. While M. pseudoshottsii and M. shottsii have been phenotypically and genotypically characterized, other less common mycobacterial isolates have not. In the present study, we describe 17 photochromogenic isolates from Chesapeake …

Molecular Mechanisms Of Poly [Adp-Ribose] Polymerase-1 In Hiv-1 Infection, Daniel Reyes

Open Access Theses & Dissertations

Poly (ADP-ribose) polymerase-1 (PARP-1) is a cellular enzyme involved in genome stability and transcriptional regulation. The role of this protein in HIV-1 infection is largely controversial. Some reports indicated a fundamental role of PARP-1 in HIV-1 DNA integration and results from other laboratories do not support these conclusions. An important characteristic in all these experiments is that the HIV-1 target cells that were used express, in addition to PARP-1, the functional homologue PARP-2. We evaluated the role of PARP-1 in the chicken B lymphoblastoid cell line DT40. These cells naturally lack PARP-2 and support the early steps of HIV infection. …

Pleiotropic Regulatory Function Of The Lysr Family Transcriptional Regulator Cpsy During Streptococcus Iniae Systemic Infection, Jonathan Paul Allen

Wayne State University Dissertations

The ability of a pathogen to metabolically adapt to the local environment for optimal expression of virulence determinants is a continued area of research. Orthologs of the Streptococcus iniae LysR family regulator CpsY have been shown to regulate methionine biosynthesis and uptake pathways, but appear to influence expression of several virulence genes as well. A S. iniae mutant with an in-frame deletion of cpsY is highly attenuated in a zebrafish infection model. The cpsY deletion mutant displays a methionine-independent growth defect in serum, which differs from the methionine-dependent defect observed for orthologous mutants of S. mutans and S. agalactiae. …

Hsv-1 Infection In Keratinocyte Cell Lines Treated With Mitotic Inhibitors, Asma A. Abbas

Browse all Theses and Dissertations

The hypothesis for this research was: Herpes simplex virus type 1 (HSV-1) infection of murine keratinocyte cell lines (HEL-30 and PAM-212) treated with mitotic inhibitors leads to silencing of virus replication. At 0.1 (Multiplicity of infection) MOI, PAM-212 keratinocytes showed some cell lysis and viral plaques were seen in HEL-30 keratinocyte cultures. PAM-212 keratinocytes, infected at 0.01 MOI, were more susceptible to the lytic effect of HSV-1 than were HEL-30 cells. In this study, 5-fluoro-2'-deoxyuridine (FUDR) treatment of both keratinocyte cell lines permitted an increase survival of HSV-1- infected keratinocytes especially for PAM-212 cell line which was further examined for …

Distribution Of Cellular Interferon Beta (Ifn-Β) In Murine Fibroblast Cell Lines Upon Infection Of Hsv-1, Rachael E. Curtis

Browse all Theses and Dissertations

The hypothesis for this study was: IFN-β expression differs between murine fibroblasts (A2R1 and L929) of different mouse strains upon infection of HSV-1. Fluorescent microscopy was used to examine localization of IFN-β in the different murine fibroblast and keratinocyte cell lines after 6 hours of infection with herpes simplex virus type-1 (HSV-1). Because keratinocytes cell lines HEL-30 and PAM-212 grew in clusters, staining patterns in individual cells could not be determined. A notable difference in localization of IFN-β immune staining was seen between the two cell lines when infected with HSV-1. The A2R1 cell line showed perinuclear (PN) localization, while …

Targeted Knockdown Of Amp-Activated Protein Kinase Alpha 1 And Alpha 2 Catalytic Subunits, Larissa J. Tangeman

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AMP-activated protein kinase (AMPK) regulates cellular metabolism and promotes ATP production when energy is depleted. Evidence suggests that AMPK may be involved in oxygen sensing by carotid body cells, which are responsible for regulating the breathing rate to maintain proper blood oxygen levels. There are two isoforms of the catalytic alpha subunit, AMPKalpha1 and AMPKalpha2, which could be involved in oxygen sensing. Here, the production of a short hairpin RNA (shRNA) targeting both catalytic isoforms of AMPK in human, mouse, and rat is described. The shRNA causes significant knockdown of both isoforms of AMPK alpha in mouse and human cells …

Strategies For Long-Term Renal Allograft Survival In Iga Nephropathy Patients, Erin E. Lintz

Browse all Theses and Dissertations

IgA nephropathy is one of the most common kidney diseases worldwide. Most IgA nephropathy patients will undergo a kidney transplant as a treatment. Treatment currently includes the use of immunosuppressants which are necessary to prevent graft rejection but present harmful side-effects when taken long-term. This review focuses on strategies which have the ability to promote tolerance of both donor and recipient cells within a transplant recipient. Such strategies allow development of mixed chimerism and thereby alleviate the need for long-term immunosuppressant usage in allograft recipients. These strategies could be applied to IgA nephropathy patients to allow kidney allograft acceptance without …

Amino Acid Substitutions Created In Reverse Transcriptase And Their Influence On Hiv-1 Mutation Frequencies, Amani Saud Alhejely

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As research has shown, a high mutation rate occurs during the reverse transcription RT process because HIV reverse transcriptase fails to correct erroneously incorporated nucleotides during the reverse transcription process. Based on various research articles, a series of amino acid substitutions created in RT were collected to find out their influence on virus mutation frequencies. Two tables were used; one for amino acid substitutions created in RT that increased the HIV-1 mutation rate and another for amino acid substitutions created in RT that decreased the HIV-1 mutation rate. The tables show which amino acid substitutions created in RT decreased or …

Developing A Quantitative Pcr Assay For Detecting Viral Vector Shedding From Animals, Swathee Chinnasamy

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Replication deficient viruses have been used widely for replacing, repairing, and deleting target genes. These recombinant viruses are tested on research animals or patients in clinical trials. Although viral vectors distribute in the body, they are also disseminated into the environment through secretion and excretion processes. By studying the extent of shedding, a proper risk assessment can be performed and appropriate biocontainment can be achieved. Adenoviral and lentiviral vectors were produced from commercially available kits. The transgene present in both vector systems was the lacZ reporter gene encoding for β-galactosidase. Primers and probes were designed for the encapsidation region of …

Detection Of Autoreactive Cd4 T Cells Using Major Histocompatibility Complex Class Ii Dextramers, Chandirasegaran Massilamany, Bijaya Upadhyaya, Arunakumar Gangaplara, Charles Kuszynski, Jay Reddy

Nebraska Center for Virology: Faculty Publications

Background: Tetramers are useful tools to enumerate the frequencies of antigen-specific T cells. However, unlike CD8 T cells, CD4 T cells - especially self-reactive cells - are challenging to detect with major histocompatibility complex (MHC) class II tetramers because of low frequencies and low affinities of their T cell receptors to MHCpeptide complexes. Here, we report the use of fluorescent multimers, designated MHC dextramers that contain a large number of peptide-MHC complexes per reagent.

Results: The utility of MHC dextramers was evaluated in three autoimmune disease models: 1) proteolipid protein (PLP) 139-151-induced experimental autoimmune encephalomyelitis in SJL/J (H-2 …

Tetherin Inhibits Prototypic Foamy Virus Release, Fengwen Xu, Juan Tan, Ruikang Liu, Dan Xu, Yue Li, Yunqi Geng, Chen Liang, Wentao Qiao

Nebraska Center for Virology: Faculty Publications

Background: Tetherin (also known as BST-2, CD317, and HM1.24) is an interferon- induced protein that blocks the release of a variety of enveloped viruses, such as retroviruses, filoviruses and herpesviruses. However, the relationship between tetherin and foamy viruses has not been clearly demonstrated.

Results: In this study, we found that tetherin of human, simian, bovine or canine origin inhibits the production of infectious prototypic foamy virus (PFV). The inhibition of PFV by human tetherin is counteracted by human immunodeficiency virus type 1 (HIV-1) Vpu. Furthermore, we generated human tetherin transmembrane domain deletion mutant (delTM), glycosyl phosphatidylinositol (GPI) anchor …

Robust Rnai-Based Resistance To Mixed Infection Of Three Viruses In Soybean Plants Expressing Separate Short Hairpins From A Single Transgene, Xiuchun Zhang, Shirley Sato, Xiaohong Ye, Anne E. Dorrance, Thomas Jack Morris, Thomas E. Clemente, Feng Qu

Nebraska Center for Virology: Faculty Publications

Transgenic plants expressing double-stranded RNA (dsRNA) of virus

origin have been previously shown to confer resistance to virus infections

through the highly conserved RNA-targeting process termed RNA silencing

or RNA interference (RNAi). In this study we applied this strategy to

soybean plants and achieved robust resistance to multiple viruses with a

single dsRNA-expressing transgene. Unlike previous reports that relied

on the expression of one long inverted repeat (IR) combining sequences

of several viruses, our improved strategy utilized a transgene designed to

express several shorter IRs. Each of these short IRs contains highly conserved

sequences of one virus, forming dsRNA of …

Kaposi Sarcoma-Associated Herpesvirus Degrades Cellular Toll-Interleukin-1 Receptor Domain-Containing Adaptor-Inducing Β-Interferon (Trif), Humera Ahmad, Rachel Gubbels, Florencia Meyer, Thomas Waterbury, Rongtuan Lin, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Kaposi sarcoma-associated herpesvirus (KSHV) is a human ƴ - herpesvirus associated with several human malignancies. The replication and transcription activator (RTA) is necessary and sufficient for the switch from KSHV latency to lytic replication. Toll-interleukin-1 receptor (TIR) domain-containing adaptorinducing β-interferon (TRIF, also called TIR-domain-containing adaptor molecule-1 (TICAM-1)) is a signaling adaptor molecule that is critically involved in the Toll-like receptor 3 (TLR-3) and TLR-4 signaling pathways for type I interferon (IFN) production, a key component of innate immunity against microbial infection. In this report, we find a new mechanism by which RTA blocks innate immunity by targeting cellular TRIF. RTA …