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2020

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Articles 61 - 90 of 459

Full-Text Articles in Microbiology

Dengue Vector Distribution And Their Infection Status In Selected Regions In Tanzania, Anitha Philbert, Amina Msonga Oct 2020

Dengue Vector Distribution And Their Infection Status In Selected Regions In Tanzania, Anitha Philbert, Amina Msonga

Tanzania Journal of Science

Dengue fever is an important arboviral infection globally. Tanzania has experienced multiple dengue outbreaks since 2010 leading to mortalities and public distress. Dengue is caused by viruses which are transmitted to humans by vector mosquitoes. Nevertheless, the abundance, distribution and extent of viral infections of these vectors are poorly understood. The aim of this study was to characterize dengue vectors and determine their virus infection rates. Adult mosquitoes were collected from selected regions in Tanzania including Dar es Salaam, Tanga, Coast, and Arusha regions using CO2 baited mosquito magnet traps between December 2018 to February 2019, additional samples were collected …


Microbiological, Physicochemical And Heavy Metals Assessments Of Soils And Selected Vegetables Grown On Rumde-Doubeli Irrigated Farmland In Yola Nigeria, Mohammed Inuwa Ja’Afaru, Joel Uyi Ewansiha, Abdulwahab Dahiru, Konjerimam Ishaku Chimbekujwo Oct 2020

Microbiological, Physicochemical And Heavy Metals Assessments Of Soils And Selected Vegetables Grown On Rumde-Doubeli Irrigated Farmland In Yola Nigeria, Mohammed Inuwa Ja’Afaru, Joel Uyi Ewansiha, Abdulwahab Dahiru, Konjerimam Ishaku Chimbekujwo

Tanzania Journal of Science

Leaf parts of vegetable plants grown on irrigated farmlands and are easily accessed by contaminants; pose greater risks of being contaminated with heavy metals. Soil, irrigation water and edible vegetable plants were collected and evaluated for concentrations of heavy metals using Atomic Absorption Spectrophotometry (AAS) and standard laboratory methods. Physicochemical parameters of irrigation water, compared with WHO limits for chloride (326.14 + 7.03 mg/L, 250 mg/L), total hardness (196.0 + 8.72 mg/L, 150 mg/L), chemical oxygen demand (286.4 ±1.35 mg/L; 150 mg/L) and alkalinity (171.0 + 4.36 mg/L, 120 mg/L) were significantly (p ˂ 0.05) higher than the control sites …


Antibacterial Activities Of The Extracts Of Allium Sativum (Garlic) And Allium Cepa (Onion) Against Selected Pathogenic Bacteria, Sherifat O. Enejiyon, Al-Hassan A. Abdulrahman, Abdulameen S. Adedeji, Ramatu Abdulsalam, Mary U. Oyedum Oct 2020

Antibacterial Activities Of The Extracts Of Allium Sativum (Garlic) And Allium Cepa (Onion) Against Selected Pathogenic Bacteria, Sherifat O. Enejiyon, Al-Hassan A. Abdulrahman, Abdulameen S. Adedeji, Ramatu Abdulsalam, Mary U. Oyedum

Tanzania Journal of Science

Although many antibiotics have been developed against bacterial diseases, the problems of antibiotic resistance and toxicity have made the continuous search for newer drugs an existential necessity. This study determined the phytochemical components and antibacterial activities of Allium sativum and Allium cepa against Salmonella typhi, Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae and Escherichia coli. The phytochemical analysis was carried out using standard methods. The antibacterial activities of the aqueous, ethanol and acetone extracts of both plants at different concentrations were determined against all the test organisms using agar well diffusion method. All the extracts were found to contain important phytochemicals …


Antibacterial Action Of Graphene Oxide Towards Bacteria And Its Toxicological Effects On Human Epidermal Keratinocytes, Thiruchelvi Pulingam Oct 2020

Antibacterial Action Of Graphene Oxide Towards Bacteria And Its Toxicological Effects On Human Epidermal Keratinocytes, Thiruchelvi Pulingam

Student Works (2020-2029)

The antibacterial nature of graphene oxide (GO) has stimulated wide interest in the medical field. Although the antibacterial activity of GO towards bacteria has been well studied, a deeper understanding of the mechanism of action of GO is still lacking. The objectives of the study were to characterize the physicochemical properties of GO, to determine the antibacterial and antibiofilm activity and the mechanistic action of GO against Gram-positive Staphylococcus aureus and Enterococcus faecalis and Gram-negative Escherichia coli and Pseudomonas aeruginosa, to determine the synergistic behaviour of GO with selected antibiotics against bacterial cells in suspension and biofilm and to determine …


Expanding Magnetic Organelle Biogenesis In The Domain Bacteria, Wei Lin, Wensi Zhang, Greig A. Paterson, Qiyun Zhu, Xiang Zhao, Rob Knight, Dennis A. Bazylinski, Andrew P. Roberts, Yongxin Pan Oct 2020

Expanding Magnetic Organelle Biogenesis In The Domain Bacteria, Wei Lin, Wensi Zhang, Greig A. Paterson, Qiyun Zhu, Xiang Zhao, Rob Knight, Dennis A. Bazylinski, Andrew P. Roberts, Yongxin Pan

Life Sciences Faculty Research

Background: The discovery of membrane-enclosed, metabolically functional organelles in Bacteria has transformed our understanding of the subcellular complexity of prokaryotic cells. Biomineralization of magnetic nanoparticles within magnetosomes by magnetotactic bacteria (MTB) is a fascinating example of prokaryotic organelles. Magnetosomes, as nano-sized magnetic sensors in MTB, facilitate cell navigation along the local geomagnetic field, a behaviour referred to as magnetotaxis or microbial magnetoreception. Recent discovery of novel MTB outside the traditionally recognized taxonomic lineages suggests that MTB diversity across the domain Bacteria are considerably underestimated, which limits understanding of the taxonomic distribution and evolutionary origin of magnetosome organelle biogenesis. Results: Here, …


Evaluation Of Semi-Quantitative Compared To Quantitative Cultures Of Tracheal Aspirates For The Yield Of Culturable Respiratory Pathogens - A Cross-Sectional Study, Salima Rattani, Joveria Farooqi, Ghazala Jabeen, Saeeda Chandio, Qaiser Kash, Aijaz Khan, Kauser Jabeen Oct 2020

Evaluation Of Semi-Quantitative Compared To Quantitative Cultures Of Tracheal Aspirates For The Yield Of Culturable Respiratory Pathogens - A Cross-Sectional Study, Salima Rattani, Joveria Farooqi, Ghazala Jabeen, Saeeda Chandio, Qaiser Kash, Aijaz Khan, Kauser Jabeen

Department of Pathology and Laboratory Medicine

Background: Diagnosis of lower respiratory tract infections (LRTI) depends on the presence of clinical, radiological and microbiological findings. Endotracheal suction aspirate (ETSA) is the commonest respiratory sample sent for culture from intubated patients. Very few studies have compared quantitative and semi-quantitative processing of ETSA cultures for LRTI diagnosis. We determined the diagnostic accuracy of quantitative and semi-quantitative ETSA culture for LRTI diagnosis, agreement between the quantitative and semi quantitative culture techniques and the yield of respiratory pathogens with both methods.
Methods: This was a cross-sectional study conducted at the Aga Khan University clinical laboratory, Karachi, Pakistan. One hundred and seventy-eight …


The Impact Of Sample Processing And Media Chemistry On The Culturable Diversity Of Bacteria Isolated From A Cave, Katey E. Bender, Katelyn Glover, Alexander Archey, Hazel A. Barton Oct 2020

The Impact Of Sample Processing And Media Chemistry On The Culturable Diversity Of Bacteria Isolated From A Cave, Katey E. Bender, Katelyn Glover, Alexander Archey, Hazel A. Barton

International Journal of Speleology

Although molecular approaches can identify members of microbial communities in the environment, genomic information does not necessarily correlate with environmental phenotype. Understanding functional roles can be done by cultivating representative species, yet the culturablility of bacteria from caves remains low, at 0.02%, limiting our understanding of microbial community interactions and processes. We have investigated several factors influencing culturability of bacteria from a single sample location in Maxwelton Sink Cave, WV, USA. Extended incubation of inoculated plates showed a significant increase in colony counts from two to four weeks, indicating that extended incubations increase culturability. There were no significant differences in …


A Mini-Tn5-Derived Transposon With Reportable And Selectable Markers Enables Rapid Generation And Screening Of Insertional Mutants In Gram-Negative Bacteria, Eric S. Nazareno, Bimala Acharya, C. Korsi Dumenyo Oct 2020

A Mini-Tn5-Derived Transposon With Reportable And Selectable Markers Enables Rapid Generation And Screening Of Insertional Mutants In Gram-Negative Bacteria, Eric S. Nazareno, Bimala Acharya, C. Korsi Dumenyo

Agricultural and Environmental Sciences Faculty Research

We re-engineered a classic tool for mutagenesis and gene expression studies in Gram-negative bacteria. Our modified Tn5-based transposon contains multiple features that allow rapid selection for mutants, direct quantification of gene expression and straightforward cloning of the inactivated gene. The promoter-less gfp-km cassette provides selection and reporter assay depending on the activity of the promoter upstream of the transposon insertion site. The cat gene facilitates positive antibiotic selection for mutants, while the narrow R6Kγ replication origin forces transposition in recipient strains lacking the pir gene and enables cloning of the transposon flanked with the disrupted gene from the chromosome. The …


Distinct Distribution Of Archaea From Soil To Freshwater To Estuary: Implications Of Archaeal Composition And Function In Different Environments, Hualong Wang, Raven Bier, Laura Zgleszewski, Marc Peipoch, Emmanuel Omondi, Atanu Mukherjee, Feng Chen, Chuanlun Zhang, Jinjun Kan Oct 2020

Distinct Distribution Of Archaea From Soil To Freshwater To Estuary: Implications Of Archaeal Composition And Function In Different Environments, Hualong Wang, Raven Bier, Laura Zgleszewski, Marc Peipoch, Emmanuel Omondi, Atanu Mukherjee, Feng Chen, Chuanlun Zhang, Jinjun Kan

Agricultural and Environmental Sciences Faculty Research

In addition to inhabiting extreme territories, Archaea are widely distributed in common environments spanning from terrestrial to aquatic environments. This study investigated and compared archaeal community structures from three different habitats (representing distinct environments): agriculture soils (from farming system trials FST, PA, United States), freshwater biofilms (from White Clay Creek, PA, United States), and estuary water (Chesapeake Bay, United States). High-throughput sequencing of 16S rRNA genes indicated that Thaumarchaeota, Euryarchaeota, Nanoarchaeota, Crenarchaeota, and Diapherotrites were the commonly found dominant phyla across these three environments. Similar to Bacteria, distinct community structure and distribution patterns for Archaea were observed in soils vs. …


Graphene-Based Electrochemical Aptasensor For The Detection Of Salmonella Typhimurium, Shalini Muniandy Oct 2020

Graphene-Based Electrochemical Aptasensor For The Detection Of Salmonella Typhimurium, Shalini Muniandy

Student Works (2020-2029)

Recent foodborne outbreaks in multiple locations necessitate the continuous development of highly sensitive and specific biosensors that offer rapid and sensitive detection of foodborne pathogens. The emergence of electrochemical aptasensor which is a compact analytical device with a combination of an aptamer as the biorecognition element integrated on the transducer surface created a breakthrough in the detection of foodborne bacterial pathogens. Graphene has emerged as a promising nanomaterial for reliable detection of pathogenic bacteria due to its exceptional properties such as high electrical conductivity, large surface to volume ratio, high mechanical strength and its unique interactions with DNA bases of …


Herb-Layer Dynamics In An Old-Growth Forest: Vegetation–Environment Relationships And Response To Invasion-Related Perturbations, Taylor M. Buskey, Margaret E. Maloney, Julia I. Chapman, Ryan W. Mcewan Oct 2020

Herb-Layer Dynamics In An Old-Growth Forest: Vegetation–Environment Relationships And Response To Invasion-Related Perturbations, Taylor M. Buskey, Margaret E. Maloney, Julia I. Chapman, Ryan W. Mcewan

Biology Faculty Publications

Temperate forests of eastern North America are subject to multiple invasions from non-native species that have the potential to drive long-term dynamics in biodiversity. Garlic mustard (Alliaria petiolata (M. Bieb.) Cavara and Grande) is an invasive plant in many deciduous forests, and management efforts often focus on removing this species to initiate native species restoration. Agrilus planipennis Fairmaire (emerald ash borer; Coleoptera: Buprestidae) is a non-native insect pest that has caused substantial loss of ash trees (Fraxinus spp. L.) in North America. Our goal was to understand how the herbaceous layer in an old-growth forest responded to the removal of …


Overview Of Plaster Creek Stewards Transpiration Rate Across Different Species Over 3 Years, Ana Singh, David P. Warners Oct 2020

Overview Of Plaster Creek Stewards Transpiration Rate Across Different Species Over 3 Years, Ana Singh, David P. Warners

Faculty and Professional Research

No abstract provided.


Diverse Community Of Arsenic Resistant Bacteria Display Arsenate Reducing Capabilities, Stephanie Maeda Oct 2020

Diverse Community Of Arsenic Resistant Bacteria Display Arsenate Reducing Capabilities, Stephanie Maeda

Undergraduate Honors Theses

Naturally found in soil and water environments arsenic is toxic to many organisms, carcinogenic to humans, and poses a significant public health risk. Yet communities of bacteria found thriving in arsenic ridden environments have evolved mechanisms to tolerate and exploit both oxidation states of this heavy metal (arsenite and arsenate). As the site of an old arsenic mine, Black Mountain Open Space Park in San Diego, California has yielded concentrations of arsenic in the soil between 111-14,800 ppm. Exceeding average arsenic soil concentrations and levels considered safe in the environment by the World Health Organization, we sought to characterize the …


Endothelial Cell Contributions To Covid-19, Alexandra E. Oxford, Fabio Halla, Evan B. Robertson, Brad E. Morrison Oct 2020

Endothelial Cell Contributions To Covid-19, Alexandra E. Oxford, Fabio Halla, Evan B. Robertson, Brad E. Morrison

Biology Faculty Publications and Presentations

Understanding of the clinical, histological and molecular features of the novel coronavirus 2019 (Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)) has remained elusive. Coronavirus disease 2019 (COVID-19) caused by this virus has unusual clinical presentation with regard to other related coronaviruses. Recent reports suggest that SARS-CoV-2, unlike other related viruses, infects and replicates within endothelial cells, which may explain a significant portion of the observed clinical pathology. Likewise, mounting evidence associates vascular and endothelial cell dysfunction with increased mortality. This review focuses on understanding how endothelial cell pathology is caused by SARS-CoV-2 at the molecular and cellular levels and how …


Cryo‑Electron Microscopy Structure Of The 70s Ribosome From Enterococcus Faecalis, Eileen L. Murphy, Kavindra V. Singh, Bryant Avila, Torsten Kleffmann, Steven T. Gregory, Barbara E. Murray, Kurt L. Krause, Reza Khayat, Gerwald Jogl Oct 2020

Cryo‑Electron Microscopy Structure Of The 70s Ribosome From Enterococcus Faecalis, Eileen L. Murphy, Kavindra V. Singh, Bryant Avila, Torsten Kleffmann, Steven T. Gregory, Barbara E. Murray, Kurt L. Krause, Reza Khayat, Gerwald Jogl

Publications and Research

Enterococcus faecalis is a gram-positive organism responsible for serious infections in humans, but as with many bacterial pathogens, resistance has rendered a number of commonly used antibiotics ineffective. Here, we report the cryo-EM structure of the E. faecalis 70S ribosome to a global resolution of 2.8 Å. Structural differences are clustered in peripheral and solvent exposed regions when compared with Escherichia coli, whereas functional centres, including antibiotic binding sites, are similar to other bacterial ribosomes. Comparison of intersubunit conformations among five classes obtained after three-dimensional classification identifies several rotated states. Large ribosomal subunit protein bL31, which forms intersubunit bridges to …


Microbial Diversity In The Sawmill Environment: Implications On The Health Of Sawmill Workers And Merchants, Nigeria, Ebere J. Okafor-Elenwo Ej, Odaro S. Imade Os, Osazee E. Izevbuwa Eo Sep 2020

Microbial Diversity In The Sawmill Environment: Implications On The Health Of Sawmill Workers And Merchants, Nigeria, Ebere J. Okafor-Elenwo Ej, Odaro S. Imade Os, Osazee E. Izevbuwa Eo

Journal of Bioresource Management

There is an increasingly high suspicion of occupational health diseases amongst workers in sawmill factories. Hence this study aimed to determine the microbial diversity in some sawmill factories in Okada, Edo State, Nigeria to evaluate potential implications of the factory’s processing area on the health of the workers and wood merchants. Bacteria and fungi count in the bioaerosols within the processing area of each factory was performed with the passive air sampling technique. While in the sawdust samples, microbial counts were carried out with the pour plate technique. Identification of the microbes was performed with macroscopic and microscopic examinations as …


A Functional K+ Channel From Tetraselmis Virus 1, A Member Of The Mimiviridae, Kerri Kukovetz, Brigitte Hertel, Christopher R. Schvarcz, Andrea Saponaro, Mirja Manthey, Ulrike Burk, Timo Greiner, Grieg F. Steward, James L. Van Etten, Anna Moroni, Gerhard Thiel, Oliver Rauh Sep 2020

A Functional K+ Channel From Tetraselmis Virus 1, A Member Of The Mimiviridae, Kerri Kukovetz, Brigitte Hertel, Christopher R. Schvarcz, Andrea Saponaro, Mirja Manthey, Ulrike Burk, Timo Greiner, Grieg F. Steward, James L. Van Etten, Anna Moroni, Gerhard Thiel, Oliver Rauh

Nebraska Center for Virology: Faculty Publications

Potassium ion (K+) channels have been observed in diverse viruses that infect eukaryotic marine and freshwater algae. However, experimental evidence for functional K+ channels among these alga-infecting viruses has thus far been restricted to members of the family Phycodnaviridae, which are large, double-stranded DNA viruses within the phylum Nucleocytoviricota. Recent sequencing projects revealed that alga-infecting members of Mimiviridae, another family within this phylum, may also contain genes encoding K+ channels. Here we examine the structural features and the functional properties of putative K+ channels from four cultivated members of Mimiviridae. While all four proteins contain variations …


Sensitivity Of Planktonic Cells Of Staphylococcus Aureus To Elevated Hydrostatic Pressure As Affected By Mild Heat, Carvacrol, Nisin, And Caprylic Acid, Jyothi George, Sadiye Aras, Md Niamul Kabir, Sabrina Wadood, Shahid Chowdhury, Aliyar Cyrus Fouladkhah Sep 2020

Sensitivity Of Planktonic Cells Of Staphylococcus Aureus To Elevated Hydrostatic Pressure As Affected By Mild Heat, Carvacrol, Nisin, And Caprylic Acid, Jyothi George, Sadiye Aras, Md Niamul Kabir, Sabrina Wadood, Shahid Chowdhury, Aliyar Cyrus Fouladkhah

Agricultural and Environmental Sciences Faculty Research

Current study investigated effects of elevated hydrostatic pressure exposure in the presence of mild heat and natural antimicrobials against Staphylococcus aureus. Hydrostatic pressure of 350 to 550 MPa with nisin (5000 IU/mL), carvacrol, or caprylic acid (0.5% v/v) were applied for the reduction in four-strain mixture of S. aureus in HEPES buffer at 4 and 40 °C for up to 7 min. Results were statistically analyzed by ANOVA and D-values were additionally calculated using best-fitted linear model. Prior to exposure to treatments at 4 °C, counts of the pathogen were 7.95 ± 0.4 log CFU/mL and were reduced (p < 0.05) to 6.44 ± 0.3 log CFU/mL after 7 min of treatment at 450 MPa. D-value associated with this treatment was 5.34 min (R2 …


Biofilm Forming Ability Of Bacteria Isolated From Dental Caries: With Reference To Streptococcus Species, Sonali Kaustubh Ambulkar, Vidya Tale, Abhijit Jadhav, Komal Kulkarni Sep 2020

Biofilm Forming Ability Of Bacteria Isolated From Dental Caries: With Reference To Streptococcus Species, Sonali Kaustubh Ambulkar, Vidya Tale, Abhijit Jadhav, Komal Kulkarni

Future Dental Journal

Dental caries is formed by the group of microorganisms attached to a tooth surface embedded in a matrix of polymers. Biofilm plays an important role in the development of dental caries, plaque and other periodontal diseases. The present study is aimed to isolate, identify and characterize bacteria from dental caries. The ability of biofilm formation of these isolates was confirmed by Congo red agar method, Tube method and Microtitre plate method. High biofilm-forming bacteria were identified by 16S rRNA sequencing. Streptococcus mutans, Streptococcus anginosus, Enterococcus faecalis and Rothia dentocariosa are the predominant biofilm forming bacteria associated with dental caries.


Human Parainfluenza Virus Fusion Complex Glycoproteins Imaged In Action On Authentic Viral Surfaces, Tara Marcink, Tong Wang, Amédée Des Georges, Matteo Porotto, Anne Moscona Sep 2020

Human Parainfluenza Virus Fusion Complex Glycoproteins Imaged In Action On Authentic Viral Surfaces, Tara Marcink, Tong Wang, Amédée Des Georges, Matteo Porotto, Anne Moscona

Advanced Science Research Center

Infection by human parainfluenza viruses (HPIVs) causes widespread lower respiratory diseases, including croup, bronchiolitis, and pneumonia, and there are no vaccines or effective treatments for these viruses. HPIV3 is a member of the Respirovirus species of the Paramyxoviridae family. These viruses are pleomorphic, enveloped viruses with genomes composed of single-stranded negative-sense RNA. During viral entry, the first step of infection, the viral fusion complex, comprised of the receptor-binding glycoprotein hemagglutininneuraminidase (HN) and the fusion glycoprotein (F), mediates fusion upon receptor binding. The HPIV3 transmembrane protein HN, like the receptor-binding proteins of other related viruses that enter host cells using …


Did You Wash Your Caving Suit? Cavers’ Role In The Potential Spread Of Pseudogymnoascus Destructans, The Causative Agent Of White-Nose Disease, Violeta Zhelyazkova, Antonia Hubancheva, Georgi Radoslavov, Nia Toshkova, Sebastien J. Puechmaille Sep 2020

Did You Wash Your Caving Suit? Cavers’ Role In The Potential Spread Of Pseudogymnoascus Destructans, The Causative Agent Of White-Nose Disease, Violeta Zhelyazkova, Antonia Hubancheva, Georgi Radoslavov, Nia Toshkova, Sebastien J. Puechmaille

International Journal of Speleology

White-Nose Disease (WND) has killed millions of hibernating bats in the US and Canada. Its causative agent, the fungus Pseudogymnoascus destructans was introduced to North America, but is native to Europe and Asia, where it is not associated with mass mortality. Although it is nearly impossible to eradicate an emerging wildlife disease, research on P. destructans spread mechanisms can aid in prevention of new introductions and development of better environmental management strategies. It is of particular importance to quantify the potential role of people visiting caves (cavers, tourists, bat researchers, etc.) whom inadvertently move P. destructans spores between sites, and …


Mechanism Of Translation Inhibition By Type Ii Gnat Toxin Atat2, Stepan V Ovchinnikov, Dmitry Bikmetov, Alexei Livenskyi, Marina Serebryakova, Brendan Wilcox, Kyle Mangano, Dmitrii I Shiriaev, Ilya A Osterman, Petr V Sergiev, Sergei Borukhov, Nora Vazquez-Laslop, Alexander S Mankin, Konstantin Severinov, Svetlana Dubiley Sep 2020

Mechanism Of Translation Inhibition By Type Ii Gnat Toxin Atat2, Stepan V Ovchinnikov, Dmitry Bikmetov, Alexei Livenskyi, Marina Serebryakova, Brendan Wilcox, Kyle Mangano, Dmitrii I Shiriaev, Ilya A Osterman, Petr V Sergiev, Sergei Borukhov, Nora Vazquez-Laslop, Alexander S Mankin, Konstantin Severinov, Svetlana Dubiley

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Type II toxin-antitoxins systems are widespread in prokaryotic genomes. Typically, they comprise two proteins, a toxin, and an antitoxin, encoded by adjacent genes and forming a complex in which the enzymatic activity of the toxin is inhibited. Under stress conditions, the antitoxin is degraded liberating the active toxin. Though thousands of various toxin-antitoxins pairs have been predicted bioinformatically, only a handful has been thoroughly characterized. Here, we describe the AtaT2 toxin from a toxin-antitoxin system from Escherichia coli O157:H7. We show that AtaT2 is the first GNAT (Gcn5-related N-acetyltransferase) toxin that specifically targets charged glycyl tRNA. In vivo, the AtaT2 …


Does The Presence Of Multiple Β-Lactamases In Gram-Negative Bacilli Impact The Results Of Antimicrobial Susceptibility Tests And Extended-Spectrum Β-Lactamase And Carbapenemase Confirmation Methods?, Fred C. Tenover, Caitlin M. Dela Cruz, Scott Dewell, Victoria M. Le, Isabella A. Tickler Sep 2020

Does The Presence Of Multiple Β-Lactamases In Gram-Negative Bacilli Impact The Results Of Antimicrobial Susceptibility Tests And Extended-Spectrum Β-Lactamase And Carbapenemase Confirmation Methods?, Fred C. Tenover, Caitlin M. Dela Cruz, Scott Dewell, Victoria M. Le, Isabella A. Tickler

Biology Faculty Publications

Objectives: Many multidrug-resistant Gram-negative bacilli (MDR-GNB) harbour multiple β-lactamases. The aim of this study was to assess the impact of multiple β-lactamase carriage on the accuracy of susceptibility tests and extended-spectrum β-lactamase (ESBL) and carbapenemase confirmation methods.

Methods: A total of 50 MDR-GNB, of which 29 carried multiple β-lactamases, underwent broth microdilution (BMD) and disk diffusion (DD) testing as well as confirmation tests for ESBLs and carbapenemases. Whole-genome sequencing (WGS) was used for β-lactamase gene identification.

Results: Categorical agreement of BMD and DD testing results ranged from 86.5 to 97.7% for 10 β-lactam agents. BMD and DD algorithms for ESBL …


Defining The Proteolytic Landscape During Enterovirus Infection., Mohsan Saeed, Sebastian Kapell, Nicholas T Hertz, Xianfang Wu, Kierstin Bell, Alison W Ashbrook, Milica Tesic Mark, Henry A Zebroski, Maxwell L Neal, Malin Flodström-Tullberg, Margaret R Macdonald, John D Aitchison, Henrik Molina, Charles M Rice Sep 2020

Defining The Proteolytic Landscape During Enterovirus Infection., Mohsan Saeed, Sebastian Kapell, Nicholas T Hertz, Xianfang Wu, Kierstin Bell, Alison W Ashbrook, Milica Tesic Mark, Henry A Zebroski, Maxwell L Neal, Malin Flodström-Tullberg, Margaret R Macdonald, John D Aitchison, Henrik Molina, Charles M Rice

Articles, Abstracts, and Reports

Viruses cleave cellular proteins to remodel the host proteome. The study of these cleavages has revealed mechanisms of immune evasion, resource exploitation, and pathogenesis. However, the full extent of virus-induced proteolysis in infected cells is unknown, mainly because until recently the technology for a global view of proteolysis within cells was lacking. Here, we report the first comprehensive catalog of proteins cleaved upon enterovirus infection and identify the sites within proteins where the cleavages occur. We employed multiple strategies to confirm protein cleavages and assigned them to one of the two enteroviral proteases. Detailed characterization of one substrate, LSM14A, a …


The Influence Of Riparian Invasion By The Terrestrial Shrub Lonicera Maackii On Aquatic Macroinvertebrates In Temperate Forest Headwater Streams, Michelle N. Little, Kevin W. Custer, Eric B. Borth, Julia I. Chapman, Mitchell J. Kukla, Corey Kuminecz, Margaret E. Maloney, Michaela J. Woods, Ryan Mcewan Sep 2020

The Influence Of Riparian Invasion By The Terrestrial Shrub Lonicera Maackii On Aquatic Macroinvertebrates In Temperate Forest Headwater Streams, Michelle N. Little, Kevin W. Custer, Eric B. Borth, Julia I. Chapman, Mitchell J. Kukla, Corey Kuminecz, Margaret E. Maloney, Michaela J. Woods, Ryan Mcewan

Biology Faculty Publications

The ecology of headwater streams is tightly linked to the riparian zone through organic matter subsidies which are highly susceptible to alteration due to biological invasion. Lonicera maackii is a non-native shrub that is a highly successful invader of headwater stream riparian zones in the American Midwest. We assessed effects on benthic macroinvertebrates across a gradient of invasion intensity from references sites with minimal invasion to a site that had a very heavy invasion. Benthic macroinvertebrates were sampled throughout the year and compositional differences were assessed using Non-metric Multidimensional Scaling ordination, and by comparing the prevalence of sensitive (Ephemeroptera, Plectoptera, …


Tick-Borne Pathogens Shape The Native Microbiome Within Tick Vectors, Abdulsalam Adegoke, Deepak Kumar, Cailyn Bobo, Muhammad Imran Rashid, Aneela Zameer Durrani, Muhammad Sohail Sajid, Shahid Karim Sep 2020

Tick-Borne Pathogens Shape The Native Microbiome Within Tick Vectors, Abdulsalam Adegoke, Deepak Kumar, Cailyn Bobo, Muhammad Imran Rashid, Aneela Zameer Durrani, Muhammad Sohail Sajid, Shahid Karim

Faculty Publications

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Ticks are blood-feeding arthropods and transmit a variety of medically important viral, bacterial, protozoan pathogens to animals and humans. Ticks also harbor a diverse community of microbes linked to their biological processes, such as hematophagy, and hence affect vector competence. The interactions between bacterial and/or protozoan pathogens and the tick microbiome is a black-box, and therefore we tested the hypothesis that the presence of a protozoan or bacterial pathogen will alter the microbial composition within a tick. Hence, this study was designed to define the microbial composition of two tick species, …


Small Molecule Synthetic Carbohydrate Receptors, Marcelo F. Bravo Carranco Sep 2020

Small Molecule Synthetic Carbohydrate Receptors, Marcelo F. Bravo Carranco

Dissertations, Theses, and Capstone Projects

Carbohydrate – receptor interactions are often involved in the attachment of viruses to host cells, and this docking is a necessary step in the virus life cycle that precedes infection and, ultimately, replication. Despite the conserved structures of the glycans involved in docking, they are still considered “undruggable”, meaning these glycans are beyond the scope of conventional pharmacological strategies. Recent advances in the development of synthetic carbohydrate receptors (SCRs) – small molecules that bind carbohydrates – could bring carbohydrate-receptor interactions within the purview of druggable targets. Here we discuss the role of carbohydrate-receptor interactions in viral infection, the evolution of …


1,4-Dioxane Biodegradation In Propanotrophs: Molecular Foundations And Implications For Environmental Remediation, Li Fei Aug 2020

1,4-Dioxane Biodegradation In Propanotrophs: Molecular Foundations And Implications For Environmental Remediation, Li Fei

Dissertations

1,4-Dioxane (dioxane) has emerged with an escalating concern given its human carcinogenicity and widespread occurrence in groundwater. Bioremediation is promising as an effective and cost-efficient treatment alternative for in situ or ex situ cleanup of dioxane and co-existing pollutants in the field. Soluble di-iron monooxygenases (SDIMOs) are reputed for their essential roles in initiating the cleavage of dioxane and other pollutants. In this doctoral dissertation, molecular foundations for SDIMOs-mediated dioxane biodegradation are untangled to promote the development and implication of site-specific bioremediation and natural attenuation strategies. This dissertation focused on propanotrophic bacteria given their pivotal roles in dioxane metabolism and …


Study Of A Putative Niche Adapting Operon In Microbes Inhabiting The Gut Of Blood Digesting Animals, Marlene Abouaassi Aug 2020

Study Of A Putative Niche Adapting Operon In Microbes Inhabiting The Gut Of Blood Digesting Animals, Marlene Abouaassi

University Scholar Projects

The sialic acid utilization (SAU) operon is a horizontally acquired gene set that allows bacteria to utilize sialic acid as an alternate source of carbon and nitrogen in the guts of blood eating animals. Sialic acid often occurs as a terminal sugar in complex glycoproteins. It functions in cell signaling and adhesion. Sialic acid is an important component of the cellular envelope of animals. Some microorganisms have evolved to decorate their own surface with sialic acid to evade the host’s immune response (molecular mimicry). The SAU operon encodes enzymes that hydrolyze sialic acid from glycoproteins, transport sialic acid into the …


Study Of A Putative Niche Adapting Operon In Microbes Inhabiting The Gut Of Blood Digesting Animals, Marlene Abouaassi Aug 2020

Study Of A Putative Niche Adapting Operon In Microbes Inhabiting The Gut Of Blood Digesting Animals, Marlene Abouaassi

Honors Scholar Theses

The sialic acid utilization (SAU) operon is a horizontally acquired gene set that allows bacteria to utilize sialic acid as an alternate source of carbon and nitrogen in the guts of blood eating animals. Sialic acid often occurs as a terminal sugar in complex glycoproteins. It functions in cell signaling and adhesion. Sialic acid is an important component of the cellular envelope of animals. Some microorganisms have evolved to decorate their own surface with sialic acid to evade the host’s immune response (molecular mimicry). The SAU operon encodes enzymes that hydrolyze sialic acid from glycoproteins, transport sialic acid into the …