Open Access. Powered by Scholars. Published by Universities.®

Pathogenic Microbiology Commons

Open Access. Powered by Scholars. Published by Universities.®

447 Full-Text Articles 1,058 Authors 83,630 Downloads 85 Institutions

All Articles in Pathogenic Microbiology

Faceted Search

447 full-text articles. Page 3 of 18.

Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs 2017 Technische Universität München, Germany

Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The human pathogen L. monocytogenes and the animal pathogen L. ivanovii, together with four other species isolated from symptom-free animals, form the "Listeria sensu stricto" clade. The members of the second clade, "Listeria sensu lato", are believed to be solely environmental bacteria without the ability to colonize mammalian hosts. To identify novel determinants that contribute to infection by L. monocytogenes, the causative agent of the foodborne disease listeriosis, we performed a genome comparison of the two clades and found 151 candidate genes that are conserved in the Listeria sensu stricto species. Two factors were investigated further in vitro and in ...


Fluorescence-Reported Allelic Exchange Mutagenesis Reveals A Role For Chlamydia Trachomatis Tmea In Invasion That Is Independent Of Host Ahnak, M. J. McKuen, Konrad E. Mueller, Y. S. Bae, Kenneth A. Fields 2017 University of Miami

Fluorescence-Reported Allelic Exchange Mutagenesis Reveals A Role For Chlamydia Trachomatis Tmea In Invasion That Is Independent Of Host Ahnak, M. J. Mckuen, Konrad E. Mueller, Y. S. Bae, Kenneth A. Fields

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Development of approaches to genetically manipulate Chlamydia is fostering important advances in understanding pathogenesis. Fluorescence-reported allelic exchange mutagenesis (FRAEM) now enables the complete deletion of specific genes in C. trachomatis L2. We have leveraged this technology to delete the coding sequences for a known type III effector. The evidence provided here indicates that CT694/CTL0063 is a virulence protein involved in chlamydial invasion. Based on our findings, we designate the gene product corresponding to ct694-ctl0063 translocated membrane-associated effector A (TmeA). Deletion of tmeA did not impact development of intracellular chlamydiae. However, the absence of TmeA manifested as a decrease in ...


Mechanism Of Candida Albicans Biofilm And Virulence Inhibition By A Bacterial Secreted Factor, Carrie Graham 2017 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Mechanism Of Candida Albicans Biofilm And Virulence Inhibition By A Bacterial Secreted Factor, Carrie Graham

UT GSBS Dissertations and Theses (Open Access)

The human microbiome is a diverse polymicrobial population comprised of both fungi and bacteria. Perturbations of the normal microbiome can have a profound impact on health, including the development of infections. Exploitation of these polymicrobial interactions has the potential to provide novel treatment and prevention strategies for infectious diseases. Enterococcus faecalis, a Gram-positive bacterium, and Candida albicans, a polymorphic fungus, occupy overlapping niches as ubiquitous constituents of the gastrointestinal and oral microbiome. Both species are also amongst the most important and problematic, opportunistic nosocomial pathogens and are often co-isolated during infection. Surprisingly, these two species antagonize each other’s virulence ...


Experimental Approaches To Understand And Control Salmonella Infection In Poultry, Yichao Yang 2017 University of Arkansas, Fayetteville

Experimental Approaches To Understand And Control Salmonella Infection In Poultry, Yichao Yang

Theses and Dissertations

Salmonella is a major foodborne pathogen around the world and chickens are the major reservoir to transmit Salmonella into the human food chain. For decreasing the infection of Salmonella, we developed six attenuated live vaccines based on Salmonella Enteritidis (SE) and Typhimurium (ST) for testing the cross-serovar and cross-serogroup protection from the challenge of Salmonella Heidelberg and Campylobacter jejuni. One of the constructed vaccine strain showed ability to protect against challenge from Salmonella Heidelberg. Even though some preventive approaches are able to decrease Salmonella colonization in the gastrointestinal tract of chickens or other farm animals, Salmonella transmission mechanisms remain unclear ...


Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone 2017 University of Arkansas, Fayetteville

Role Of Incompatibility Group 1 (Inci1) Plasmid-Encoded Factors On Salmonella Enterica Antimicrobial Resistance And Virulence, Pravin Raghunath Kaldhone

Theses and Dissertations

Foodborne illnesses are a leading cause of infectious diseases in the world. Among enteric organisms Salmonella is a key pathogen. It’s high prevalence in poultry and other food-animal sources make it imperative to study. Salmonella has the ability to modify its genetic content with help of mobile genetic elements such as plasmids. Incompatibiltiy group 1 (IncI1) plasmids are commonly reported in Salmonella. This study evaluates role on IncI1 plasmids in antimicrobial resistance and virulence in Salmonella. Genetic determinants of resistance and virulence are noted among our IncI1-containing Salmonella isolates. These genetic elements are also transferable and reported to carry ...


Changing Antimalarial Drug Sensitivities In Uganda, Stephanie Alexis Rasmussen 2017 Dominican University of California

Changing Antimalarial Drug Sensitivities In Uganda, Stephanie Alexis Rasmussen

Graduate Master's Theses, Capstones, and Culminating Projects

Dihydroartemisinin-piperaquine (DP) has demonstrated excellent efficacy for the treatment and prevention of malaria in Uganda. However, resistance to both components of this regimen has emerged in Southeast Asia. The efficacy of artemether-lumefantrine, the first-line regimen to treat malaria in Uganda, has also been excellent, but continued pressure may select for parasites with decreased sensitivity to lumefantrine. To gain insight into current drug sensitivity patterns, ex vivo sensitivities were assessed and genotypes previously associated with altered drug sensitivity were characterized for 58 isolates collected in Tororo, Uganda from subjects presenting in 2016 with malaria from the community or as part of ...


The Molecular Mechanism Of N-Acetylglucosamine Side-Chain Attachment To The Lancefield Group A Carbohydrate In Streptococcus Pyogenes, Jeffrey Rush, Rebecca J. Edgar, Pan Deng, Jing Chen, Haining Zhu, Nina M. van Sorge, Andrew J. Morris, Konstantin V. Korotkov, Natalia Korotkova 2017 University of Kentucky

The Molecular Mechanism Of N-Acetylglucosamine Side-Chain Attachment To The Lancefield Group A Carbohydrate In Streptococcus Pyogenes, Jeffrey Rush, Rebecca J. Edgar, Pan Deng, Jing Chen, Haining Zhu, Nina M. Van Sorge, Andrew J. Morris, Konstantin V. Korotkov, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

In many Lactobacillales species (i.e. lactic acid bacteria), peptidoglycan is decorated by polyrhamnose polysaccharides that are critical for cell envelope integrity and cell shape and also represent key antigenic determinants. Despite the biological importance of these polysaccharides, their biosynthetic pathways have received limited attention. The important human pathogen, Streptococcus pyogenes, synthesizes a key antigenic surface polymer, the Lancefield group A carbohydrate (GAC). GAC is covalently attached to peptidoglycan and consists of a polyrhamnose polymer, with N-acetylglucosamine (GlcNAc) side chains, which is an essential virulence determinant. The molecular details of the mechanism of polyrhamnose modification with GlcNAc are currently ...


Human Rickettsial Pathogen Modulates Arthropod Organic Anion Transporting Polypeptide And Tryptophan Pathway For Its Survival In Ticks, Vikas Taank, Shovan Dutta, Amrita Dasgupta, Durland Fish, John F. Anderson, Hameeda Sultana, Girish Neelakanta 2017 Old Dominion University

Human Rickettsial Pathogen Modulates Arthropod Organic Anion Transporting Polypeptide And Tryptophan Pathway For Its Survival In Ticks, Vikas Taank, Shovan Dutta, Amrita Dasgupta, Durland Fish, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

The black-legged tick Ixodes scapularis transmits the human anaplasmosis agent, Anaplasma phagocytophilum. In this study, we show that A. phagocytophilum specifically up-regulates I. scapularis organic anion transporting polypeptide, isoatp4056 and kynurenine amino transferase (kat), a gene involved in the production of tryptophan metabolite xanthurenic acid (XA), for its survival in ticks. RNAi analysis revealed that knockdown of isoatp4056 expression had no effect on A. phagocytophilum acquisition from the murine host but affected the bacterial survival in tick cells. Knockdown of the expression of kat mRNA alone or in combination with isoatp4056 mRNA significantly affected A. phagocytophilum survival and isoatp4056 expression ...


The Effect Of Diet On Midgut And Resulting Changes In Infectiousness Of Acmnpv Baculovirus In Trichoplusia Ni, Elizabeth Chen 2017 The University of Western Ontario

The Effect Of Diet On Midgut And Resulting Changes In Infectiousness Of Acmnpv Baculovirus In Trichoplusia Ni, Elizabeth Chen

Electronic Thesis and Dissertation Repository

The cabbage looper, Trichoplusia ni, a global generalist lepidopteran pest, has developed resistance to many synthetic and biological insecticides, requiring effective and environmentally acceptable alternatives. One possibility is the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). This baculovirus is highly infectious for T. ni, with potential as a biocontrol agent, however, its effectiveness is strongly influenced by dietary context. In this study, microscopy and transcriptomics were used to examine how the efficacy of this virus was affected when T. ni larvae were raised on different diets. Larvae raised on potato host plants had lower chitinase and chitin deacetylase transcript levels and thickened ...


T-Cell Responses Targeting Hiv Nef Uniquely Correlate With Infected Cell Frequencies After Long-Term Antiretroviral Therapy., Allison S Thomas, Kimberley L Jones, Rajesh T Gandhi, Deborah K McMahon, Joshua C Cyktor, Dora Chan, Szu-Han Huang, Ronald Truong, Alberto Bosque, Amanda B Macedo, Colin Kovacs, Erika Benko, Joseph J Eron, Ronald J Bosch, Christina M Lalama, Samuel Simmens, Bruce D Walker, John W Mellors, R Brad Jones 2017 George Washington University

T-Cell Responses Targeting Hiv Nef Uniquely Correlate With Infected Cell Frequencies After Long-Term Antiretroviral Therapy., Allison S Thomas, Kimberley L Jones, Rajesh T Gandhi, Deborah K Mcmahon, Joshua C Cyktor, Dora Chan, Szu-Han Huang, Ronald Truong, Alberto Bosque, Amanda B Macedo, Colin Kovacs, Erika Benko, Joseph J Eron, Ronald J Bosch, Christina M Lalama, Samuel Simmens, Bruce D Walker, John W Mellors, R Brad Jones

Microbiology, Immunology, and Tropical Medicine Faculty Publications

HIV-specific CD8+ T-cell responses limit viral replication in untreated infection. After the initiation of antiretroviral therapy (ART), these responses decay and the infected cell population that remains is commonly considered to be invisible to T-cells. We hypothesized that HIV antigen recognition may persist in ART-treated individuals due to low-level or episodic protein expression. We posited that if persistent recognition were occurring it would be preferentially directed against the early HIV gene products Nef, Tat, and Rev as compared to late gene products, such as Gag, Pol, and Env, which have higher barriers to expression. Using a primary cell model of ...


Heightened Circulating Levels Of Antimicrobial Peptides In Tuberculosis-Diabetes Co-Morbidity And Reversal Upon Treatment, Nathella Pavan Kumar, Kadar Moideen, Vijay Viswanathan, Shanmugam Sivakumar, Pradeep A. Menon, Hardy Kornfeld, Subash Babu 2017 National Institutes of Health-NIRT-International Center for Excellence in Research

Heightened Circulating Levels Of Antimicrobial Peptides In Tuberculosis-Diabetes Co-Morbidity And Reversal Upon Treatment, Nathella Pavan Kumar, Kadar Moideen, Vijay Viswanathan, Shanmugam Sivakumar, Pradeep A. Menon, Hardy Kornfeld, Subash Babu

Open Access Articles

BACKGROUND: The association of antimicrobial peptides (AMPs) with tuberculosis-diabetes comorbidity (PTB-DM) is not well understood.

METHODS: To study the association of AMPs with PTB-DM, we examined the systemic levels of cathelicidin (LL37), human beta defensin- 2 (HBD2), human neutrophil peptides 1-3, (HNP1-3) and granulysin in individuals with either PTB-DM, PTB, latent TB (LTB) or no TB infection (NTB).

RESULTS: Circulating levels of cathelicidin and HBD2 were significantly higher and granulysin levels were significantly lower in PTB-DM compared to PTB, LTB or NTB, while the levels of HNP1-3 were significantly higher in PTB-DM compared to LTB or NTB individuals. Moreover, the ...


Trypanosome Lytic Factor Mediated Immunity Against Leishmania Sp., Jyoti Pant 2017 The Graduate Center, City University of New York

Trypanosome Lytic Factor Mediated Immunity Against Leishmania Sp., Jyoti Pant

All Dissertations, Theses, and Capstone Projects

Trypanosome Lytic Factor (TLF) is an innate immunity complex that was originally discovered to protect against African Trypanosomes. The major components of TLF are Apolipoprotein A1 (APOA1), Apolipoprotein L1 (APOL1) and HPR (Haptoglobin Related Protein), where APOL1 is necessary and sufficient for trypanolysis. Recently we have shown that TLF ameliorates infections by cutaneous Leishmania species. Here we investigated the effect of different primate and human TLF against different Leishmania sp. Our result shows that TLF kills metacyclic promastigotes of cutaneous Leishmania sp. within immune cells such as neutrophils and macrophages by two different mechanism. Using transiently transfected and germline transgenic ...


The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry 2017 University of Kentucky

The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The FeoABC ferrous transporter is a wide-spread bacterial system. While the feoABC locus is regulated by a number of factors in the bacteria studied, we have previously found that regulation of feoABC in Yersinia pestis appears to be unique. None of the non-iron responsive transcriptional regulators that control expression of feoABC in other bacteria do so in Y. pestis. Another unique factor is the iron and Fur regulation of the Y. pestis feoABC locus occurs during microaerobic but not aerobic growth. Here we show that this unique iron-regulation is not due to a unique aspect of the Y. pestis Fur ...


Pseudogymnoascus Destructans Transcriptome Changes During White-Nose Syndrome Infections, Sophia M. Reeder, Jonathan M. Palmer, Jenni M. Prokkola, Thomas M. Lilley, DeeAnn M. Reeder, Ken Field 2017 Bucknell University

Pseudogymnoascus Destructans Transcriptome Changes During White-Nose Syndrome Infections, Sophia M. Reeder, Jonathan M. Palmer, Jenni M. Prokkola, Thomas M. Lilley, Deeann M. Reeder, Ken Field

Faculty Journal Articles

White nose syndrome (WNS) is caused by the psychrophilic fungus Pseudogymnoascus destructans that can grow in the environment saprotrophically or parasitically by infecting hibernating bats. Infections are pathological in many species of North American bats, disrupting hibernation and causing mortality. To determine what fungal pathways are involved in infection of living tissue, we examined fungal gene expression using RNA-Seq. We compared P. destructans gene expression when grown in culture to that during infection of a North American bat species, Myotis lucifugus, that shows high WNS mortality. Cultured P. destructans was grown at 10 to 14 C and P. destructans growing ...


Candida And Pseudomonas Interact To Enhance Mucosal Infection In Transparent Zebrafish, Audrey C. Bergeron 2017 The University of Maine

Candida And Pseudomonas Interact To Enhance Mucosal Infection In Transparent Zebrafish, Audrey C. Bergeron

Electronic Theses and Dissertations

Polymicrobial communities exist throughout the human body and include both fungi and bacteria. During disease, cross-kingdom interactions among bacteria, fungi, and/or the immune system can alter virulence and lead to complex polymicrobial infections. The fungus C. albicans is among the most commonly isolated fungi in the context of fungal-bacterial co-infections and is often accompanied by the bacterium P. aeruginosa at a variety of sites throughout the body including mucosal tissues such as the lung. In vitro, C. albicans and P. aeruginosa have a cyclic, bi-directional, and largely antagonistic relationship, but these interactions do not account for the role of ...


Quorum Sensing Signals Produced By Heterotrophic Bacteria In Black Band Disease (Bbd) Of Corals And Their Potential Role In Bbd Pathogenesis, Chinmayee D. Bhedi 2017 Florida International University

Quorum Sensing Signals Produced By Heterotrophic Bacteria In Black Band Disease (Bbd) Of Corals And Their Potential Role In Bbd Pathogenesis, Chinmayee D. Bhedi

FIU Electronic Theses and Dissertations

Black band disease (BBD) of corals is a temperature dependent, highly virulent, polymicrobial disease affecting reef-building corals globally. The microbial consortium of BBD is primarily comprised of functional physiological groups that include photosynthetic cyanobacteria, sulfate reducers, sulfide oxidizers and a vast repertoire of heterotrophic bacteria. Quorum sensing (QS), the cell-density dependent communication phenomenon in bacteria, is known to induce expression of genes for a variety of virulence factors in diseases worldwide. Microbes capable of QS release signals such as acyl homoserine lactones (AHLs) and autoinducer-2 (AI-2), which coordinate microbial interaction. The focus of the present study was to investigate the ...


Intestinal Organoids Model Human Responses To Infection By Commensal And Shiga Toxin Producing Escherichia Coli, Sayali S. Karve, Suman Pradhan, Doyle V. Ward, Alison A. Weiss 2017 University of Cincinnati

Intestinal Organoids Model Human Responses To Infection By Commensal And Shiga Toxin Producing Escherichia Coli, Sayali S. Karve, Suman Pradhan, Doyle V. Ward, Alison A. Weiss

Open Access Articles

Infection with Shiga toxin (Stx) producing Escherichia coli O157:H7 can cause the potentially fatal complication hemolytic uremic syndrome, and currently only supportive therapy is available. Lack of suitable animal models has hindered study of this disease. Induced human intestinal organoids (iHIOs), generated by in vitro differentiation of pluripotent stem cells, represent differentiated human intestinal tissue. We show that iHIOs with addition of human neutrophils can model E. coli intestinal infection and innate cellular responses. Commensal and O157:H7 introduced into the iHIO lumen replicated rapidly achieving high numbers. Commensal E. coli did not cause damage, and were completely contained ...


Phenomenological And Molecular Basis Of The Cnidarian Immune System, Tanya Brown 2017 Florida International University

Phenomenological And Molecular Basis Of The Cnidarian Immune System, Tanya Brown

FIU Electronic Theses and Dissertations

Coral reefs are one of the most diverse ecosystems on the planet due partially to the habitat structure provided by corals. Corals are long lived organisms that can live for hundreds of years and as a result growth of many species is very slow. As a result of this, recovery of corals from disease outbreaks is very slow and difficult and therefore the ecosystem is deteriorating rapidly. Due to this increase in disease and its detrimental effect on coral reefs, it has become imperative to study how corals respond to disease outbreaks. The response of the coral to pathogens is ...


Pas Signaling Mechanisms In Aer And Aer2, Darysbel Garcia 2017 Loma Linda University

Pas Signaling Mechanisms In Aer And Aer2, Darysbel Garcia

Loma Linda University Electronic Theses, Dissertations & Projects

PAS domains are widespread signal sensors that share a conserved three-dimensional αβ fold that consists of a central β-sheet flanked by several α- helices. The aerotaxis receptor Aer from Escherichia coli and the Aer2 chemoreceptor from Pseudomonas aeruginosa both contain PAS domains. Aer senses oxygen (O2) indirectly via an FAD cofactor bound to its PAS domain, while Aer2 directly binds O2 to its PAS b-type heme cofactor. The Aer and Aer2 PAS domains both interact with a signal transduction domain known as a HAMP domain. The PAS-HAMP arrangement differs between Aer and Aer2, with Aer- PAS residing adjacent to its ...


Therapeutic Antibody Against Neisseria Gonorrhoeae Lipooligosaccharide, A Phase-Variable Virulence Factor, Srinjoy Chakraborti 2017 University of Massachusetts Medical School

Therapeutic Antibody Against Neisseria Gonorrhoeae Lipooligosaccharide, A Phase-Variable Virulence Factor, Srinjoy Chakraborti

GSBS Dissertations and Theses

Neisseria gonorrhoeae (Ng) which causes gonorrhea has become multidrug-resistant, necessitating the development of novel therapeutics and vaccines. mAb 2C7 which targets an epitope within an important virulence factor, the lipooligosaccharide (LOS), is a candidate therapeutic mAb. Ninety-four percent of clinical isolates express the 2C7-epitope which is also a vaccine target.

Ng expresses multiple LOS(s) due to phase-variation (pv) of LOS glycosyltransferase (lgt) genes. mAb 2C7 reactivity requires a lactose extension from the LOS core Heptose (Hep) II (i.e. lgtG ‘ON’ [G+]). Pv results in HepI with: two (2-), three (3-), four (4-), or five (5-) hexoses (Hex). How ...


Digital Commons powered by bepress