Microbiology Commons^™

Bryostatins: Biological Context And Biotechnological Prospects, Amaro E. Trindade-Silva, Grace E. Lim-Fong, Koty H. Sharp

Arts & Sciences Faculty Publications

Coral animals harbor diverse microorganisms in their tissues, including archaea, bacteria, viruses, and Bryostatins are a family of protein kinase C modulators that have potential applications in biomedicine. Found in miniscule quantities in a small marine invertebrate, lack of supply has hampered their development. In recent years, bryostatins have been shown to have potent bioactivity in the central nervous system, an uncultivated marine bacterial symbiont has been shown to be the likely natural source of the bryostatins, the bryostatin biosynthetic genes have been identified and characterized, and bryostatin analogues with promising biological activity have been developed and tested. Challenges in …

Genetic Diversity Among Plasmodium Falciparum Field Isolates In Pakistan Measured With Pcr Genotyping Of The Merozoite Surface Protein 1 And 2, Najia Ghanchi, Andreas Martensson, Johan Ursing, Sana Jafri, Sandor Bereczky, Rabia Hussain, Mohammad Asim Beg

Department of Pathology and Laboratory Medicine

Background:The genetic diversity of Plasmodium falciparum has been extensively studied in various parts of the world. However, limited data are available from Pakistan. This study aimed to establish molecular characterization of P. falciparum field isolates in Pakistan measured with two highly polymorphic genetic markers, i.e. the merozoite surface protein 1 (msp-1) and 2 (msp-2).
Methods:Between October 2005 and October 2007, 244 blood samples from Patients with symptomatic blood-slide confirmed P. falciparum mono-infections attending the Aga Khan University Hospital, Karachi, or its collection units located in Sindh and Baluchistan provinces, Pakistan were collected. The genetic diversity of P. falciparum …

Oceanic Heterotrophic Bacterial Nutrition By Semilabile Dom As Revealed By Data Assimilative Modeling, Yw Luo, M. A.M. Friedrichs, Sc Doney, Mj Church, Hw Ducklow

VIMS Articles

Previous studies have focused on the role of labile dissolved organic matter (DOM) (defined as turnover time of similar to 1 d) in supporting heterotrophic bacterial production, but have mostly neglected semilabile DOM (defined as turnover time of similar to 100 to 1000 d) as a potential substrate for heterotrophic bacterial growth. To test the hypothesis that semilabile DOM supports substantial amounts of heterotrophic bacterial production in the open ocean, we constructed a 1-dimensional epipelagic ecosystem model and applied it to 3 open ocean sites: the Arabian Sea, Equatorial Pacific and Station ALOHA in the North Pacific Subtropical Gyre. The …

Analysing The Effects Of Loss Of Sin3 In Drosophila Melanogaster, Aishwarya Swaminathan

Wayne State University Dissertations

Sin3A has been previously shown to be an essential gene for Drosophila viability and is implicated in the regulation of cell cycle. In this study, we show that SIN3 is not only required for embryonic viability but also for post-embryonic development. Genetic analysis suggests that the different isoforms of SIN3 may regulate unique sets of genes during development. The developmental lethality occurring due to ubiquitous knock down of SIN3 is hypothesized to be to the result of defects in cell proliferation. Conditional knock down of SIN3 in the wing discs results in a curly wing phenotype in the adult fly. …

Characterization Of Biofilms Formed By Mycobacterium Aviumn Subspecies Paratuberculosis In Psychologically Relevant Conditions, Richard Brunner

All Graduate Theses, Dissertations, and Other Capstone Projects

Mycobacterium avium subspecies paratuberculosis (Mpt) is the cause of Johne's disease, a gastrointestinal disease that mainly affects ruminants. Despite being an obligate intracellular pathogen, Mpt can survive in the environment for months. How Mpt survives in the environment has yet to be determined, but one tactic Mpt may use is the formation of biofilms. Biofilms may provide sufficient protection and allow Mpt endure in the environment until a new host is encountered. The conditions affecting Mpt biofilm formation have not been investigated. Both in the host and in the environment, Mpt experiences physiological stresses that may induce biofilm formation including …

The Construction And Analysis Of Marker Gene Libraries, S.M. Short, F. Chen, Steven Wilhelm

Microbiology Publications and Other Works

Marker genes for viruses are typically amplified from aquatic samples to determine whether specific viruses are present in the sample, or to examine the diversity of a group of related viruses. In this chapter, we will provide an overview of common methods used to amplify, clone, sequence, and analyze virus marker genes, and will focus our discussion on viruses infecting algae, bacteria, and heterotrophic flagellates. Within this chapter, we endeavor to highlight critical aspects and components of these methods. To this end, instead of providing a detailed experimental protocol for each of the steps involved in examining virus marker gene …

Determining Rates Of Virus Production In Aquatic Systems By The Virus Reduction Approach,, M.G. Weinbauer, J.M. Rowe, Steven Wilhelm

Microbiology Publications and Other Works

The reduction approach to assess virus production and the prokaryotic mortality by viral lysis stops new infection by reducing total virus abundance (and thus virus–host contacts). This allows for easy enumeration of viruses that originate from lysis of already infected cells due to the decreased abundance of free virus particles. This reoccurrence can be quantified and used to assess production and cell lysis rates. Several modifications of the method are presented and compared. The approaches have great potential for elucidating trends in virus production rates as well as for making generalized estimates of the quantitative effects of viruses on marine …

Animal Models Of Alzheimer's Disease, Gemma Casadesus, Gary Arendash, Frank Laferla, Mike Mcdonald

Molecular Biosciences Faculty Publications

No abstract provided.

Comparing Models Of Evolution For Ordered And Disordered Proteins, Celeste J. Brown, Audra K. Johnson, Gary W. Daughdrill

Molecular Biosciences Faculty Publications

Most models of protein evolution are based upon proteins that form relatively rigid 3D structures. A significant fraction of proteins, the so-called disordered proteins, do not form rigid 3D structures and sample a broad conformational ensemble. Disordered proteins do not typically maintain long-range interactions, so the constraints on their evolution should be different than ordered proteins. To test this hypothesis, we developed and compared models of evolution for disordered and ordered proteins. Substitution matrices were constructed using the sequences of putative homologs for sets of experimentally characterized disordered and ordered proteins. Separate matrices, at three levels of sequence similarity ( …

The Role Of Cuticle, Fatty Acids, And Lipid Signaling In Plant Defense, Ye Xia

Theses and Dissertations--Plant Pathology

Systemic acquired resistance (SAR) is initiated upon recognition of specific microbial effectors by cognate plant resistance proteins and immunizes distal tissues of plants against secondary infections. SAR involves the generation of a mobile signal at the site of primary infection, which then translocates to and activates defense responses in the distal tissues via some unknown mechanism(s). This study shows that an ACYL CARRIER PROTEIN 4 (ACP4), GLABRA1 (GL1) and ACYL CARRIER BINDING PROTEINS (ACBP) are required for the processing of the mobile SAR signal in distal tissues of Arabidopsis. Although acp4, gl1 and acbp plants generate the mobile signal, …

The Immune Response In The Central Nervous System During West Nile Virus Persistence, Barbara Sharon Stewart

Legacy Theses & Dissertations (2009 - 2024)

West Nile virus (WNV) persists in a wide array of hosts ranging from mice to humans. In convalescent humans, WNV RNA persists in urine for up to 6.7 years, and IgM antibody against WNV persists in serum for up to 12 months post-inoculation (p.i.). Previous work using the mouse model demonstrated that WNV persists in central nervous system (CNS) tissues as infectious virus and as RNA for up to 4 months and 6 months p.i., respectively. In this study, we sought to elucidate the mechanism for viral persistence in the CNS using the mouse model. Characterization of the leukocyte infiltrate …

Bioinformatic And Sequence Analysis Of Four Resuscitation Promoting Factor (Rpf) Gene Homologues In Mycobacterium Avium Subsp. Paratuberculosis (Mpt), And Expression Of The Putative Mpt Rpfb In Escherichia Coli., David Dale Hedlund

All Graduate Theses, Dissertations, and Other Capstone Projects

Mycobacterium avium subsp. paratuberculosis (Mpt), the causative agent of Johne's disease (JD), is a global problem in the agricultural industry. It is estimated that 25% of all U.S. dairy herds are JD positive. One obstacle in the management of JD is the lack a sensitive diagnostic test for use during the early stages of infection. Resuscitation promoting factors (Rpf) are proteins that promote the growth of many species of Actinobacteria. If Rpf proteins could enhance the growth of Mpt, the sensitivity of diagnostic fecal culture could be improved, and the impact of JD on the dairy industry would be significantly …

Copper Isotope Fractionation During Surface Adsorption And Intracellular Incorporation By Bacteria, Jesica Urbina Navarrete

Open Access Theses & Dissertations

Copper isotopes may prove to be a useful tool for investigating bacteria-metal interactions recorded in natural waters, soils, and rocks. However, experimental data that constrain Cu isotope fractionation in biologic systems are limited and unclear. In this study we utilized Cu isotopes (65Cu) as a tool to investigate Cu-bacteria interactions, including surface adsorption and intracellular incorporation. Experiments were conducted with individual Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacterial species as well as with bacterial consortia from several natural environments. Adsorption experiments were conducted with live or dead cells over the pH range 2.5 to 6. Surface adsorption of Cu …

Rev Interacts With Tubulin Heterodimers To Cause Cell Cycle Defects, Poornima Kotha Lakshmi Narayan

Browse all Theses and Dissertations

Rev is a regulatory protein that plays an important role in the replication of HIV virus by post-transcriptionally promoting expression of viral proteins late in infection. Rev expression also slows cell growth, leads to an accumulation of cells in G2/M specifically before the spindle checkpoint, and can produce changes in ploidy. Because Rev is capable of depolymerizing microtubules (MTs) in vitro, possibly by a mechanism shared with Kinesin-13 proteins, themselves potent cellular MT depolymerases, I tested the hypothesis that these cellular defects were due to an interaction between Rev and tubulin.

To this end, Rev and select Rev mutants defective …

The Im-9 Cell Line: A Model For Evaluating Tcdd-Induced Modulation Of The Polymorphic Human Hs1,2 Enhancer Within The 3' Immunoglobulin Heavy Chain Regulatory Region, Ruth C. Chambers-Turner

Browse all Theses and Dissertations

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a disrupter, of B-cell differentiation, induces binding of the aryl hydrocarbon receptor (AhR) nuclear complex to dioxin responsive elements (DRE) within the mouse immunoglobulin heavy chain regulatory region (3'IgHRR), and produces a marked inhibition of 3'IgHRR activation, IgH expression, and antibody secretion in a well-characterized mouse B-cell line (CH12.LX). The mouse 3'IgHRR consists of at least four enhancers (hs3a; hs1,2; hs3b; hs4), and is highly homologous with the three enhancers (hs3; hs1,2; hs4) of the human 3'IgHRR. A polymorphism of the human hs1,2 enhancer (resulting in varying numbers of tandem repeats containing a DRE and κB site) has …

Thermocrinis Minervae Sp. Nov., A Hydrogen And Sulfur-Oxidizing, Thermophilic Member Of The Aquificales From A Costa Rican Terrestrial Hot Spring, Sara L. Caldwell, Yitai Liu, Isabel Ferrera, Terry Beveridge, Anna-Louise Reysenbach

Biology Faculty Publications and Presentations

A thermophilic bacterium, designated strain CR11T , was isolated from a filamentous sample collected from a terrestrial hot spring on the south-western foothills of the Rincón volcano in Costa Rica. The Gram-negative cells are approximately 2.4–3.9 mm long and 0.5–0.6 mm wide and are motile rods with polar flagella. Strain CR11T grows between 65 and 85 6C (optimum 75 6C, doubling time 4.5 h) and between pH 4.8 and 7.8 (optimum pH 5.9–6.5). The isolate grows chemolithotrophically with S0 , S2O2{ 3 or H2 as the electron donor and with O2 (up to 16 %, v/v) as the sole electron …

Plasmid Injection And Application Of Electric Pulses Alter Endogenous Mrna And Protein Expression In B16.F10 Mouse Melanomas, L. C. Heller, Y. L. Cruz, B. Ferraro, H. Yang, R. Heller

Bioelectrics Publications

The application of electric pulses to tissues causes cell membrane destabilization, allowing exogenous molecules to enter the cells. This delivery technique can be used for plasmid gene therapy. Reporter gene expression after plasmid delivery with eight representative published protocols was compared in B16.F10 mouse melanoma tumors. This expression varied significantly based on the pulse parameters utilized for delivery. To observe the possible influence of plasmid injection and/or pulse application on endogenous gene expression, levels of stress-related mRNAs 4 and 24 h after delivery were determined by PCR array. Increases in mRNA levels for several inflammatory chemokines and cytokines were observed …

Increased Perfusion And Angiogenesis In A Hindlimb Ischemia Model With Plasmid Fgf-2 Delivered By Noninvasive Electroporation, B. Ferraro, Y. L. Cruz, M. Baldwin, D. Coppola, R. Heller

Bioelectrics Publications

Gene therapy approaches delivering fibroblast growth factor-2 (FGF-2) have shown promise as a potential treatment for increasing blood flow to ischemic limbs. Currently, effective noninvasive techniques to deliver plasmids encoding genes of therapeutic interest, such as FGF-2, are limited. We sought to determine if intradermal injection of plasmid DNA encoding FGF-2 (pFGF) followed by noninvasive cutaneous electroporation (pFGFE+) could increase blood flow and angiogenesis in a rat model of hindlimb ischemia. pFGFE+ or control treatments were administered on postoperative day 0. Compared to injection of pFGF alone (pFGFE-), delivery of pFGFE+ significantly increased FGF-2 expression for 10 days. Further, the …

The Microscope (2010-2011), Department Of Microbiology

The Microscope

No abstract provided.

Biosynthesis Of Exopolysaccharides From Lactic Acid Bacteria And Evaluation Of Their Prebiotic Potential, Colette Ann Forde

Theses

In this study, two strains of lactic acid bacteria (LAB) namely Weissella kimchii F28 and W. confusa MGl were used for the production of exopolysaccharides (EPS) from sucrose. Both strains produced glucan polysaccharides. In the case of W. kimchii F28, the EPS isolation procedure was performed six times, making modifications in order to optimize the yield of EPS. The maximum yield of EPS for this strain was 16 g per litre of culture. In the case of W. confusa MGl, the EPS isolation procedure was followed five times, resulting in a maximum yield of EPS for this strain of 34.4 …