Floxed-Cassette Allelic Exchange Mutagenesis Enables Markerless Gene Deletion In Chlamydia Trachomatis And Can Reverse Cassette-Induced Polar Effects,
2018
University of Kentucky
Floxed-Cassette Allelic Exchange Mutagenesis Enables Markerless Gene Deletion In Chlamydia Trachomatis And Can Reverse Cassette-Induced Polar Effects, Gabrielle Keb, Robert Hayman, Kenneth A. Fields
Microbiology, Immunology, and Molecular Genetics Faculty Publications
As obligate intracellular bacteria, Chlamydia spp. have evolved numerous, likely intricate, mechanisms to create and maintain a privileged intracellular niche. Recent progress in elucidating and characterizing these processes has been bolstered by the development of techniques enabling basic genetic tractability. Florescence-reported allelic exchange mutagenesis (FRAEM) couples chromosomal gene deletion with the insertion of a selection cassette encoding antibiotic resistance and green fluorescent protein (GFP). Similar to other bacteria, many chlamydial genes exist within polycistronic operons, raising the possibility of polar effects mediated by insertion cassettes. Indeed, FRAEM-mediated deletion of Chlamydia trachomatis tmeA negatively impacts the expression of tmeB. We …
Assembly And Display Of Surface Proteins In Actinomyces Oris,
2018
The University of Texas M D Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences
Assembly And Display Of Surface Proteins In Actinomyces Oris, Sara Siegel
Dissertations and Theses (Open Access)
Bacteria are an integral part of human health and disease. In the human host, dental plaques form as a result of up to 700 individual bacterial species colonizing oral surfaces and forming a multispecies biofilm. These biofilms are the cause of prevalent human diseases such as dental caries, gingivitis, and periodontitis. The microbes present in the oral biofilm are highly spatially and temporally structured and require a primary colonizing species to adhere to host tissue. As an important primary colonizer of the oral biofilm, the actinobacterium Actinomyces oris utilizes cell wall anchored proteins and glycoconjugates to initiate adherence to host …
Biofilm Producing Clinical Staphylococcus Aureus Isolates Augmented Prevalence Of Antibiotic Resistant Cases In Tertiary Care Hospitals Of Nepal,
2018
Tribhuvan University
Biofilm Producing Clinical Staphylococcus Aureus Isolates Augmented Prevalence Of Antibiotic Resistant Cases In Tertiary Care Hospitals Of Nepal, Sarita Manandhar, Anjana Singh, Ajit Varma, Shanti Pandey, Neeraj Shrivastava
Student Publications
Staphylococcus aureus, a notorious human pathogen, is a major cause of the community as well as healthcare associated infections. It can cause a diversity of recalcitrant infections mainly due to the acquisition of resistance to multiple drugs, its diverse range of virulence factors, and the ability to produce biofilm in indwelling medical devices. Such biofilm associated chronic infections often lead to increase in morbidity and mortality posing a high socio-economic burden, especially in developing countries. Since biofilm formation and antibiotic resistance function dependent on each other, detection of biofilm expression in clinical isolates would be advantageous in treatment decision. …
Triatomines: Trypanosomatids, Bacteria, And Viruses Potential Vectors?,
2018
Universidade de Brasília
Triatomines: Trypanosomatids, Bacteria, And Viruses Potential Vectors?, Caroline Barreto Viera, Yanna Reis Praça, Kaio Luis Da Silva Bentes, Paula Beatriz Santiago, Sofia Marcelino Martins Silva, Gabriel Dos Santos Silva, Flávia Nader Motta, Izabela Marques Dourado Bastos, Jaime Martins De Santana, Carla Nunes De Araújo
Harold W. Manter Laboratory of Parasitology: Library Materials
Triatominae bugs are the vectors of Chagas disease, a major concern to public health especially in Latin America, where vector-borne Chagas disease has undergone resurgence due mainly to diminished triatomine control in many endemic municipalities. Although the majority of Triatominae species occurs in the Americas, species belonging to the genus Linshcosteus occur in India, and species belonging to the Triatoma rubrofasciata complex have been also identified in Africa, the Middle East, South-East Asia, and in the Western Pacific. Not all of Triatominae species have been found to be infected with Trypanosoma cruzi, but the possibility of establishing vector transmission …
Triatomines: Trypanosomatids, Bacteria, And Viruses Potential Vectors? [Review],
2018
Universidade de Brasília
Triatomines: Trypanosomatids, Bacteria, And Viruses Potential Vectors? [Review], Caroline Barreto Vieira, Yanna Reis Praça, Kaio Luís Da Silva Bentes, Paula Beatriz Santiago, Sofia Marcelino Martins Silva, Gabriel Dos Santos Silva, Flávia Nader Motta, Izabela Marques Dorado Bastos, Jaime Martins De Santana, Carla Nunes De Araújo
Harold W. Manter Laboratory of Parasitology: Library Materials
Triatominae bugs are the vectors of Chagas disease, a major concern to public health especially in Latin America, where vector-borne Chagas disease has undergone resurgence due mainly to diminished triatomine control in many endemic municipalities. Although the majority of Triatominae species occurs in the Americas, species belonging to the genus Linshcosteus occur in India, and species belonging to the Triatoma rubrofasciata complex have been also identified in Africa, the Middle East, South-East Asia, and in the Western Pacific. Not all of Triatominae species have been found to be infected with Trypanosoma cruzi, but the possibility of establishing vector transmission …
Identification And Heterologous Reconstitution Of A 5-Alk(En)Ylresorcinol Synthase From Endophytic Fungus Shiraia Sp. Slf14,
2018
Utah State University
Identification And Heterologous Reconstitution Of A 5-Alk(En)Ylresorcinol Synthase From Endophytic Fungus Shiraia Sp. Slf14, Huiwen Yan, Lei Sun, Jinge Huang, Yixing Qiu, Fuchao Xu, Riming Yan, Du Zhu, Wei Wang, Jixun Zhan
Biological Engineering Faculty Publications
A new type III polyketide synthase gene (Ssars) was discovered from the genome of Shiraia sp. Slf14, an endophytic fungal strain from Huperzia serrata. The intron-free gene was cloned from the cDNA and ligated to two expression vectors pET28a and YEpADH2p-URA3 for expression in Escherichia coli BL21(DE3) and Saccharomyces cerevisiae BJ5464, respectively. SsARS was efficiently expressed in E. coli BL21(DE3), leading to the synthesis of a series of polyketide products. Six major products were isolated from the engineered E. coli and characterized as 1,3-dihydroxyphenyl-5-undecane, 1,3-dihydroxyphenyl-5-cis-6'-tridecene,1,3-dihydroxyphenyl-5-tridecane, 1,3-dihydroxyphenyl-5-cis-8'-pentadecene, 1,3-dihydroxyphenyl-5-pentadecane and 1,3-dihydroxyphenyl-5-cis-10'-heptadecene, respectively, …
Simulating Antibiotic Resistance In The Computer Lab And Biology Lab: Ideas For Undergraduate Projects,
2018
The New School
Simulating Antibiotic Resistance In The Computer Lab And Biology Lab: Ideas For Undergraduate Projects, Anne E. Yust
Annual Symposium on Biomathematics and Ecology Education and Research
No abstract provided.
Synergism Of Mild Heat And High-Pressure Pasteurization Against Listeria Monocytogenes And Natural Microflora In Phosphate-Buffered Saline And Raw Milk,
2018
Tennessee State University
Synergism Of Mild Heat And High-Pressure Pasteurization Against Listeria Monocytogenes And Natural Microflora In Phosphate-Buffered Saline And Raw Milk, Abimbola Allison, Shahid Chowdhury, Aliyar Fouladkhah
Agricultural and Environmental Sciences Faculty Research
As many as 99% of illnesses caused by Listeria monocytogenes are foodborne in nature, leading to 94% hospitalizations, and are responsible for the collective annual deaths of 266 American adults. The current study is a summary of microbiological hurdle validation studies to investigate synergism of mild heat (up to 55 °C) and elevated hydrostatic pressure (up to 380 MPa) for decontamination of Listeria monocytogenes and natural background microflora in raw milk and phosphate-buffered saline. At 380 MPa, for treatments of 0 to 12 min, d-values of 3.47, 3.15, and 2.94 were observed for inactivation of the pathogen at 4, 25, …
Oxygen Deprivation Influences The Survival Of Listeria Monocytogenes In Gerbils,
2018
Missisippi State University
Oxygen Deprivation Influences The Survival Of Listeria Monocytogenes In Gerbils, Jillian Harris, Oindrila Paul, Si Hong Park, Sally White, Khemraj Budachetri, Daniel M. Mcclung, Jessica G. Wilson, Alicia K. Olivier, Justin A. Thornton, Paul R. Broadway, Steven C. Ricke, Janet R. Donaldson
Faculty Publications
Listeria monocytogenes is a facultative anaerobic foodborne pathogen capable of surviving harsh environments. Recent work has indicated that anaerobic conditions increase the resistance capability of certain strains to environmental stressors. The goal of the study was to conduct a preliminary study to determine whether exposure to anaerobic conditions prior to infection increases the ability to survive in vivo. Gerbils were inoculated with one of five doses of the L. monocytogenes strain F2365 by oral gavage: phosphate-buffered saline (control), 5 × 106 colony forming units aerobic culture (low aerobic), 5 × 108 aerobic culture (high aerobic), 5 × 10 …
Identification Of Microbiota Associated With The Ectosymbiotic Community Structure Of The Appalachian Brook Crayfish (Cambarus Bartonii),
2018
Liberty University
Identification Of Microbiota Associated With The Ectosymbiotic Community Structure Of The Appalachian Brook Crayfish (Cambarus Bartonii), Matthew M. Cooke 6268927, Luke T. Fischer, Taylor Griffin, Sherrie Jeffers
Montview Journal of Research & Scholarship
Microbes play a significant role in ecosystems, effecting the vital functions of other organisms, interspecies relationships, and population sizes. Based upon previous research (Skelton et al., 2016), it has been hypothesized that crayfish symbionts (branchiobdellidans) play a significant role in regulating the amount of microbiota associated with the host. A growing body of knowledge is known regarding both the condition of gill fouling and the annelid worm’s symbiotic relationship with the crayfish (Skelton et al., 2016; Skelton et al., 2016). However, there is little to no evidence available concerning the bacteria’s role in the process (Skelton et al., 2016). Microbial …
Characterization Of The Protective Role Of Th17 Cells In An Fc Receptor-Targeted Vaccine Strategy Against Fracisella Tularensis Infection,
2018
Seton Hall University
Characterization Of The Protective Role Of Th17 Cells In An Fc Receptor-Targeted Vaccine Strategy Against Fracisella Tularensis Infection, Kyle Devenney
Seton Hall University Dissertations and Theses (ETDs)
Using a murine model, we have previously showed that targeting an inactivated form of F.tularensis (iFt) bacteria to Fcg receptors by utilizing an IgG2a, anti-LPS monoclonal antibody (mAb) provides 100% protection against a lethal dose with the live vaccine strain (LVS). The binding of anti-LPS monoclonal antibodies and iFt create an immune complex (mAb-iFt) allowing the Fc-region of the antibody to target Fc receptors expressed on antigen presenting cells, leading to a more robust and effective processing and presentation of the bacterial antigens. Although the resulting protective response generated relies on both humoral and cell-mediated immunity, in our study we …
Transcriptional Regulation Of Icaadbc By Icar And Tcar In Staphylococcus Epidermidis,
2018
University of Nebraska Medical Center
Transcriptional Regulation Of Icaadbc By Icar And Tcar In Staphylococcus Epidermidis, Tramy Hoang
Theses & Dissertations
Biofilm formation is the primary virulence factor in Staphylococcus epidermidis. Polysaccharide intercellular adhesin (PIA) is an adhesive molecule and a significant component of the biofilm matrix. It is synthesized by the products of the icaADBC operon whose regulation has been shown to involve environmental factors as well as many transcriptional regulators. Of these regulators, we explored the function of the repressors IcaR and TcaR and their roles in directly influencing icaADBC transcription and PIA synthesis. Based on previous observations that icaADBC positive clinical isolates of S. epidermidis are highly variable in PIA synthesis and biofilm formation, our goal was to …
Green Tea Polyphenol Epigallocatechin-3-Gallate-Stearate Inhibits The Growth Of Streptococcus Mutans: A Promising New Approach In Caries Prevention,
2018
Montclair State University
Green Tea Polyphenol Epigallocatechin-3-Gallate-Stearate Inhibits The Growth Of Streptococcus Mutans: A Promising New Approach In Caries Prevention, Amy Lynn Melok, Lee Lee, Siti Ayuni Mohamed Yussof, Tinchun Chu
Department of Biology Faculty Scholarship and Creative Works
Streptococcus mutans (S. mutans) is the main etiological bacteria present in the oral cavity that leads to dental caries. All of the S. mutans in the oral cavity form biofilms that adhere to the surfaces of teeth. Dental caries are infections facilitated by the development of biofilm. An esterified derivative of epigallocatechin-3-gallate (EGCG), epigallocatechin-3-gallate-stearate (EGCG-S), was used in this study to assess its ability to inhibit the growth and biofilm formation of S. mutans. The effect of EGCG-S on bacterial growth was evaluated with colony forming units (CFU) and log reduction; biofilm formation was qualitatively determined by Congo red assay, …
High-Throughput Nanoliter Dispensing Device For Biological Applications,
2018
Purdue University
High-Throughput Nanoliter Dispensing Device For Biological Applications, Cole Reynolds, Euiwon Bae Dr., J Paul Robinson Dr.
The Summer Undergraduate Research Fellowship (SURF) Symposium
Pathogen identification is a field that can contribute largely to the prevention of the spreading of illness and disease. In the past, pathogen identification has been a long and arduous process due to the time-consuming processes and steps that requires technician’s time and effort. With new technologies emerging however, screening of bacteria colonies can be done in a quick and high-throughput way. The problem is that using the current methods, bacteria cannot be transferred to petri dishes fast enough to keep up with the new screening methods. The current study focuses on exploring different methods to create an ergonomic device …
Genomic Analysis Of 48 Paenibacillus Larvae Bacteriophages,
2018
University of Nevada, Las Vegas
Genomic Analysis Of 48 Paenibacillus Larvae Bacteriophages, Casey Stamereilers, Christopher P. Fajardo, Jamison K. Walker, Katterinne N. Mendez, Eduardo Castro-Nallar, Julianne H. Grose, Sandra Hope, Philippos K. Tsourkas
Life Sciences Faculty Research
The antibiotic-resistant bacterium Paenibacillus larvae is the causative agent of American foulbrood (AFB), currently the most destructive bacterial disease in honeybees. Phages that infect P. larvae were isolated as early as the 1950s, but it is only in recent years that P. larvae phage genomes have been sequenced and annotated. In this study we analyze the genomes of all 48 currently sequenced P. larvae phage genomes and classify them into four clusters and a singleton. The majority of P. larvaephage genomes are in the 38–45 kbp range and use the cohesive ends (cos) DNA-packaging strategy, while a minority have genomes …
Arthropod Transcriptional Activator Protein-1 (Ap-1) Aids Tick-Rickettsial Pathogen Survival In The Cold,
2018
Old Dominion University
Arthropod Transcriptional Activator Protein-1 (Ap-1) Aids Tick-Rickettsial Pathogen Survival In The Cold, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta
Biological Sciences Faculty Publications
Ixodes scapularis ticks transmit several pathogens to humans including rickettsial bacterium, Anaplasma phagocytophilum. Here, we report that A. phagocytophilum uses tick transcriptional activator protein-1 (AP-1) as a molecular switch in the regulation of arthropod antifreeze gene, iafgp. RNAi-mediated silencing of ap-1 expression significantly affected iafgp gene expression and A. phagocytophilum burden in ticks upon acquisition from the murine host. Gel shift assays provide evidence that both the bacterium and AP-1 influences iafgp promoter and expression. The luciferase assays revealed that a region of approximately 700 bp upstream of the antifreeze gene is sufficient for AP-1 binding to promote …
A Broad Spectrum Racemase In Pseudomonas Putida Kt2440 Plays A Key Role In Amino Acid Catabolism,
2018
University of California - San Francisco
A Broad Spectrum Racemase In Pseudomonas Putida Kt2440 Plays A Key Role In Amino Acid Catabolism, Atanas D. Radkov, Luke A. Moe
Plant and Soil Sciences Faculty Publications
The broad-spectrum amino acid racemase (Alr) of Pseudomonas putida KT2440 preferentially interconverts the L- and D-stereoisomers of Lys and Arg. Despite conservation of broad-spectrum racemases among bacteria, little is known regarding their physiological role. Here we explore potential functional roles for Alr in P. putida KT2440. We demonstrate through cellular fractionation that Alr enzymatic activity is found in the periplasm, consistent with its putative periplasm targeting sequence. Specific activity of Alr is highest during exponential growth, and this activity corresponds with an increased accumulation of D-Lys in the growth medium. An alr gene knockout strain (Δalr) was generated …
Pseudomonas Pb1-Like Phages: Whole Genomes From Metagenomes Offer Insight Into An Abundant Group Of Bacteriophages,
2018
Loyola University Chicago
Pseudomonas Pb1-Like Phages: Whole Genomes From Metagenomes Offer Insight Into An Abundant Group Of Bacteriophages, Siobhan C. Watkins, Emily Sible, Catherine Putonti
Biology: Faculty Publications and Other Works
Despite the abundance, ubiquity and impact of environmental viruses, their inherent genomic plasticity and extreme diversity pose significant challenges for the examination of bacteriophages on Earth. Viral metagenomic studies have offered insight into broader aspects of phage ecology and repeatedly uncover genes to which we are currently unable to assign function. A combined effort of phage isolation and metagenomic survey of Chicago’s nearshore waters of Lake Michigan revealed the presence of Pbunaviruses, relatives of the Pseudomonas phage PB1. This prompted our expansive investigation of PB1-like phages. Genomic signatures of PB1-like phages and Pbunaviruses were identified, permitting the unambiguous distinction between …
Inhibition Of Listeria Monocytogenes By Human Gut Bacteria,
2018
Department of Biological Sciences, Cork Institute of Technology
Inhibition Of Listeria Monocytogenes By Human Gut Bacteria, Patrycja Sylvia Olesky
Masters
Listeria monocytogenes is a foodborne pathogen, which continues to be problematic to the food industry due to its ability survive within food products and persist within food processing environments. The growing trend towards natural food preservatives and antimicrobial agents increases the need for the development of novel, natural anti-Listeria agents. Evidence presented in the literature suggests that the human gut microbiota is a reservoir of novel antimicrobial agents. It was therefore hypothesized that novel anti-Listeria agents are produced by human gut-derived bacteria. The objective of this study was to isolate and characterize gut bacteria with anti-Listeria monocytogenes activity. A total …
Ms Analysis Of A Dilution Series Of Bacteria: Phytoplankton To Improve Detection Of Low Abundance Bacterial Peptides,
2018
Old Dominion University
Ms Analysis Of A Dilution Series Of Bacteria: Phytoplankton To Improve Detection Of Low Abundance Bacterial Peptides, Emma Timmins-Schiffman, Molly P. Mikan, Ying Sonia Ting, H. Rodger Harvey, Brook L. Nunn
OES Faculty Publications
Assigning links between microbial activity and biogeochemical cycles in the ocean is a primary objective for ecologists and oceanographers. Bacteria represent a small ecosystem component by mass, but act as the nexus for both nutrient transformation and organic matter recycling. There are limited methods to explore the full suite of active bacterial proteins largely responsible for degradation. Mass spectrometry (MS)-based proteomics now has the potential to document bacterial physiology within these complex systems. Global proteome profiling using MS, known as data dependent acquisition (DDA), is limited by the stochastic nature of ion selection, decreasing the detection of low abundance peptides. …
