Life Sciences Commons^™

The Regulation Landscape Of Mapk Signaling Cascade For Thwarting Bacillus Thuringiensis Infection In An Insect Host, Zhaojiang Guo, Shi Kang, Qingjun Wu, Shaoli Wang, Neil Crickmore, Xuguo Zhou, Alejandra Bravo, Mario Soberón, Youjun Zhang

Entomology Faculty Publications

Host-pathogen interactions are central components of ecological networks where the MAPK signaling pathways act as central hubs of these complex interactions. We have previously shown that an insect hormone modulated MAPK signaling cascade participates as a general switch to trans-regulate differential expression of diverse midgut genes in the diamondback moth, Plutella xylostella (L.) to cope with the insecticidal action of Cry1Ac toxin, produced by the entomopathogenic bacterium Bacillus thuringiensis (Bt). The relationship between topology and functions of this four-tiered phosphorylation signaling cascade, however, is an uncharted territory. Here, we carried out a genome-wide characterization of all the MAPK orthologs …

In Situ Imaging Of Bacterial Outer Membrane Projections And Associated Protein Complexes Using Electron Cryo-Tomography, Mohammed Kaplan, Georges Chreifi, Lauren Ann Metskas, Janine Liedtke, Cecily R. Wood, Catherine M. Oikonomou, William J. Nicolas, Poorna Subramanian, Lori A. Zacharoff, Yuhang Wang, Yi-Wei Chang, Morgan Beeby, Megan J. Dobro, Yongtao Zhu, Mark J. Mcbride, Ariane Briegel, Carrie L. Shaffer, Grant J. Jensen

Veterinary Science Faculty Publications

The ability to produce outer membrane projections in the form of tubular membrane extensions (MEs) and membrane vesicles (MVs) is a widespread phenomenon among diderm bacteria. Despite this, our knowledge of the ultrastructure of these extensions and their associated protein complexes remains limited. Here, we surveyed the ultrastructure and formation of MEs and MVs, and their associated protein complexes, in tens of thousands of electron cryo-tomograms of ~90 bacterial species that we have collected for various projects over the past 15 years (Jensen lab database), in addition to data generated in the Briegel lab. We identified outer MEs and MVs …

Host Phylogeny And Diet Shape Gut Microbial Communities Within Bamboo-Feeding Insects, Kuanguan Huang, Jie Wang, Junhao Huang, Shouke Zhang, Alfried P. Vogler, Quanquan Liu, Yongchun Li, Maowei Yang, You Li, Xuguo Zhou

Entomology Faculty Publications

The gut microbiome plays an important role in a host’s development and adaption to its dietary niche. In this study, a group of bamboo-feeding insects are used to explore the potential role of the gut microbiota in the convergent adaptation to extreme diet specialization. Specifically, using a 16S rRNA marker and an Illumina sequencing platform, we profiled the microbial communities of 76 gut samples collected from nine bamboo-feeding insects, including both hemimetabolous (Orthoptera and Hemiptera) and holometabolous (Coleoptera and Lepidoptera) species, which are specialized in three distinct dietary niches: bamboo leaf, shoot, and sap. The gut microbiota of these insects …

Toward The Discovery Of Biological Functions Associated With The Mechanosensor Mtl1p Of Saccharomyces Cerevisiae Via Integrative Multi-Omics Analysis, Nelson Martínez-Matías, Nataliya Chorna, Sahily González-Crespo, Lilliam Villanueva, Ingrid Montes-Rodríguez, Loyda M. Melendez-Aponte, Abiel Roche-Lima, Kelvin Carrasquillo-Carrión, Ednalise Santiago-Cartagena, Brian C. Rymond, Mohan Babu, Igor Stagljar, José R. Rodríguez-Medina

Biology Faculty Publications

Functional analysis of the Mtl1 protein in Saccharomyces cerevisiae has revealed that this transmembrane sensor endows yeast cells with resistance to oxidative stress through a signaling mechanism called the cell wall integrity pathway (CWI). We observed upregulation of multiple heat shock proteins (HSPs), proteins associated with the formation of stress granules, and the phosphatase subunit of trehalose 6-phosphate synthase which suggests that mtl1Δ strains undergo intrinsic activation of a non-lethal heat stress response. Furthermore, quantitative global proteomic analysis conducted on TMT-labeled proteins combined with metabolome analysis revealed that mtl1Δ strains exhibit decreased levels of metabolites of carboxylic acid metabolism, decreased …

Metabolomics-Based Analysis Of Miniature Flask Contents Identifies Tobacco Mixture Use Among The Ancient Maya, Mario Zimmermann, Korey J. Brownstein, Luis Pantoja Díaz, Iliana Ancona Aragón, Scott R. Hutson, Barry Kidder, Shannon Tushingham, David R. Gang

Anthropology Faculty Publications

A particular type of miniature ceramic vessel locally known as “veneneras” is occasionally found during archaeological excavations in the Maya Area. To date, only one study of a collection of such containers successfully identified organic residues through coupled chromatography–mass spectrometry methods. That study identified traces of nicotine likely associated with tobacco. Here we present a more complete picture by analyzing a suite of possible complementary ingredients in tobacco mixtures across a collection of 14 miniature vessels. The collection includes four different vessel forms and allows for the comparison of specimens which had previously formed part of museum exhibitions with recently …

Characterizing The Physiology And Genetics Of Contact Dependent Growth Inhibiton Systems In Burkholderia Species, Alice Elizabeth Oates

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Contact-dependent growth inhibition (CDI) systems mediate interbacterial competition. The genes encoding these systems are widespread among Gram-negative bacteria, including Burkholderia pathogens. CDI systems of Burkholderia species are composed of two-partner secretion pathway proteins and function to deliver the toxic C-terminus of a polymorphic surface-exposed exoprotein BcpA (Burkholderia CDI protein A) to the cytoplasm of neighboring recipient bacteria upon cell-cell contact. Specific outer and inner membrane proteins facilitate BcpA translocation both out of the donor bacterium and into the recipient cell cytoplasm. Most Burkholderia species-specific CDI translocation factors in recipient cells are unknown. BcpA intoxication functions as a mechanism by …

Entry And Replication Of Negative-Strand Rna Viruses, Kerri Boggs

Theses and Dissertations--Molecular and Cellular Biochemistry

Hendra virus (HeV) and human metapneumovirus (HMPV) are negative-sense, singled-stranded RNA viruses. The paramyxovirus HeV is classified as a biosafety level 4 pathogen due to its high fatality rate and the lack of a human vaccine or antiviral treatment. HMPV is a widespread pneumovirus that causes respiratory tract infections which are particularly dangerous for young children, immunocompromised individuals, and the elderly. Like HeV, no vaccines or therapies are available to combat HMPV infections. These viruses fuse their lipid envelopes with a cell to initiate infection. Blocking cell entry is a promising approach for antiviral development, and many vaccines are designed …

Substrate Trafficking Within The Type Vii Secretion Systems Of Pathogenic Mycobacteria, Zachary A. Williamson

Theses and Dissertations--Molecular and Cellular Biochemistry

Tuberculosis (TB), primarily caused by infection of Mycobacterium tuberculosis (Mtb) in the lungs, is the deadliest infectious bacterial disease killing 1.5 million people annually. A major determinant of virulence is active secretion through three specialized type VII secretion (ESX) systems; ESX-1, ESX-3, and ESX-5. A large group of substrates exported by the ESX systems is the PE (Proline-Glutamine) and PPE (Proline-Proline-Glutamate) families of proteins, which are highly expanded in the pathogenic species of Mycobacteria and encompass over 7% of Mtb’s genome coding capacity. PE and PPE proteins interact together to form PE-PPE heterodimers, and are secreted through …

Application Of Genetic Techniques To Investigate Chlamydia Trachomatis Type Iii Secretion Effector Biology, Gabrielle Keb

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Chlamydia trachomatis is the causative agent of the most reported bacterial sexually transmitted disease in the United States. The establishment of an intracellular niche within mucosal epithelium is sufficient to drive immunopathology and disease sequela. As obligate intracellular bacteria, Chlamydia spp. have evolved numerous mechanisms for establishing an intracellular growth environment. The type III secretion system (T3SS) delivers effector proteins to the host cytosol and is essential for C. trachomatis invasion and development. The effectors TmeA, TmeB, and TarP, are all secreted during C. trachomatis invasion. TarP and TmeA have been associated with manipulation of actin networks and are …

Circadian Rhythmicity And Melatonin Sensitivity In The Human Gut Commensal Bacterium Klebsiella Aerogenes, Kinga Graniczkowska

Theses and Dissertations--Biology

While the expression of circadian rhythms is nearly universal among multicellular eukaryotic organisms, demonstration of this phenomenon in prokaryotes has been largely restricted to photosynthetic cyanobacteria until very recently. Further, growing interest in gastrointestinal microbiomes has revealed a complex temporal relationship between the gastrointestinal clock and the bacterial microbiome within. At least one member of the gut microbiome, Klebsiella (née Enterobacter) aerogenes, responds to the indoleamine hormone melatonin, secreted by the gastrointestinal system itself. Further research revealed that K. aerogenes also expresses a circadian rhythm in motility and gene expression that is temperature compensated. Although rhythmicity is unaltered …

The Roles Of The Actin Network And Co-Opted Host Factors In Tbsv Replication, Melissa Gabriela Molho Medina

Theses and Dissertations--Plant Pathology

Positive-stranded (+) RNA viruses are the largest family of viruses that infect plants, causing important economic losses in different crops. Tomato bushy stunt virus (TBSV), a small positive-stranded RNA virus, has emerged as a model virus to study virus-host interactions. TBSV encodes for only five proteins, therefore, to infect the host cell TBSV co-opts selected host components and subverts specific molecular pathways.

Firstly, I performed a proteomic screening using Arabidopsis proteins. I found that TBSV viral replication proteins interact with 88 host proteins, including the ubiquitin-conjugating enzyme 2 (Ubc2), fructose 1,6 biphosphate aldolase (Fba1), and several members of the Hps70 …