Publications by authors named "Brent Weatherly"

This study examined the relationship between glycans, metabolites, and development in . Samples of N2 animals were synchronized and grown to five different time points ranging from L1 to a mixed population of adults, gravid adults, and offspring. Each time point was replicated seven times.

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Mass spectrometry (MS) is one of the most effective techniques for high-throughput, high-resolution characterization of glycan structures. Although many software applications have been developed over the last decades for the interpretation of MS data of glycan structures, only a few are capable of dealing with the large data sets produced by glycomics analysis. Furthermore, these applications utilize databases that can lead to redundant glycan annotations and do not support post-processing of the data within the software or by third party applications.

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-GlcNAc is a regulatory post-translational modification of nucleocytoplasmic proteins that has been implicated in multiple biological processes, including transcription. In humans, single genes encode enzymes for its attachment (-GlcNAc transferase (OGT)) and removal (-GlcNAcase (OGA)). An X-chromosome exome screen identified a missense mutation, which encodes an amino acid in the tetratricopeptide repeat, in (759G>T (p.

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Background: The protozoan parasite Trypanosoma cruzi, causative agent of Chagas disease, depends upon a cell surface-expressed trans-sialidase (ts) to avoid activation of complement-mediated lysis and to enhance intracellular invasion. However these functions alone fail to account for the size of this gene family in T. cruzi, especially considering that most of these genes encode proteins lacking ts enzyme activity.

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Human embryonic stem cells (hESCs) have received considerable attention due to their therapeutic potential and usefulness in understanding early development and cell fate commitment. In order to appreciate the unique properties of these pluripotent, self-renewing cells, we have performed an in-depth multidimensional fractionation followed by LC-MS/MS analysis of the hESCs harvested from defined media to elucidate expressed, phosphorylated, O-linked β-N-acetylglucosamine (O-GlcNAc) modified, and secreted proteins. From the triplicate analysis, we were able to assign more than 3000 proteins with less than 1% false-discovery rate.

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Unlabelled: The tumor microenvironment including glial cells and their inflammatory products regulates brain tumor development and progression. We have previously established that human glioma cells are exquisitely sensitive to IL-1 stimulation leading us to undertake a comparative analysis of the secretome of unstimulated and cytokine (IL-1)-stimulated glioblastoma cells. We performed label-free quantitative proteomic analysis and detected 190 proteins which included cytokines, chemokines, growth factors, proteases, cell adhesion molecules, extracellular matrix (ECM) and related proteins.

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Label-free quantification is a powerful tool for the measurement of protein abundances by mass spectrometric methods. To maximize quantifiable identifications, MS(1)-based methods must balance the collection of survey scans and fragmentation spectra while maintaining reproducible extracted ion chromatograms (XIC). Here we present a method which increases the depth of proteome coverage over replicate data-dependent experiments without the requirement of additional instrument time or sample prefractionation.

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The endomembrane system is a complex and dynamic intracellular trafficking network. It is very challenging to track individual vesicles and their cargos in real time; however, affinity purification allows vesicles to be isolated in their natural state so that their constituent proteins can be identified. Pioneering this approach in plants, we isolated the SYP61 trans-Golgi network compartment and carried out a comprehensive proteomic analysis of its contents with only minimal interference from other organelles.

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Background: Trypanosoma cruzi is a protozoan parasite and the etiologic agent of Chagas disease, an important public health problem in Latin America. T. cruzi is diploid, almost exclusively asexual, and displays an extraordinarily diverse population structure both genetically and phenotypically.

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Unlike other eukaryotes, the protein-coding genes of Trypanosoma cruzi are arranged in large polycistronic gene clusters transcribed by polymerase II (Pol II). Thus, it is thought that trypanosomes rely solely on posttranscriptional processes to regulate gene expression. Here, we show that the glucosylated thymine DNA base (β-d-glucosyl-hydroxymethyluracil or base J) is present within sequences flanking the polycistronic units (PTUs) in T.

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Background: Chronic chagasic cardiomyopathy is a debilitating and frequently fatal outcome of human infection with the protozoan parasite, Trypanosoma cruzi. Microarray analysis of gene expression during the T. cruzi life-cycle could be a valuable means of identifying drug and vaccine targets based on their appropriate expression patterns, but results from previous microarray studies in T.

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With the recent completion of the Brugia malayi genome, proteomics offers a new resource for a deeper understanding of the biology of filarial parasites. We employed 2-dimensional (2D) gel electrophoresis followed by peptide mass fingerprinting on a matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometer to identify Brugia adult worm proteins and then determined which proteins were recognized by the host humoral immune response. We identified 18 unique proteins, several of which were determined to be antigenic by immunoblot.

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Background: In contrast to the essentially fully assembled genome sequences of the kinetoplastid pathogens Leishmania major and Trypanosoma brucei the assembly of the Trypanosoma cruzi genome has been hindered by its repetitive nature and the fact that the reference strain (CL Brener) is a hybrid of two distinct lineages. In this work, the majority of the contigs and scaffolds were assembled into pairs of homologous chromosomes based on predicted parental haplotype, inference from TriTryp synteny maps and the use of end sequences from T. cruzi BAC libraries.

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Background: Previously, we identified a set of HLA-A020.1-restricted trans-sialidase peptides as targets of CD8+ T cell responses in HLA-A0201+ individuals chronically infected by T. cruzi.

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Background: Diagnosis of Trypanosoma cruzi infection by direct pathogen detection is complicated by the low parasite burden in subjects persistently infected with this agent of human Chagas disease. Determination of infection status by serological analysis has also been faulty, largely due to the lack of well-characterized parasite reagents for the detection of anti-parasite antibodies.

Methods: In this study, we screened more than 400 recombinant proteins of T.

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Background: The alpha-Proteobacteria are capable of interaction with eukaryotic cells, with some members, such as Ochrobactrum anthropi, capable of acting as human pathogens. O. anthropi has been the cause of a growing number of hospital-acquired infections; however, little is known about its growth, physiology and metabolism.

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We report the first proteomic analysis of the insoluble sub-proteome of the alkaliphilic and halotolerant deep-sea bacterium Oceanobacillus iheyensis HTE831. A multidimensional gel-based and gel-free analysis was utilised and a total of 4352 peptides were initially identified by automated MS/MS identification software. Automated curation of this list using PROVALT reduced our peptide list to 467 uniquely identified peptides that resulted in the positive identification of 153 proteins.

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We report the first large-scale gel-free proteomic analysis of the soluble subproteome of the emerging pathogen Ochrobactrum anthropi. Utilizing our robust offline multidimensional protein identification protocol, a total of 57 280 peptides were initially identified utilizing automated MS/MS analysis software. We describe our investigation of the heuristic protein validation tool PROVALT and demonstrate its ability to increase the speed and accuracy of the curation process of large-scale proteomic datasets.

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To further our understanding of the biology of the thermophilic bacterium Geobacillus thermoleovorans T80, we now report the first proteomic analysis of the insoluble subproteome of this isolate. A combination of both shotgun and multidimensional methodologies were utilized, and a total of 8628 peptides was initially identified by automated MS/MS identification software. Curation of these peptides led to a final list of 184 positive protein identifications.

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CD8+ T cells are crucial for control of a number of medically important protozoan parasites, including Trypanosoma cruzi, the agent of human Chagas disease. Yet, in contrast to the wealth of information from viral and bacterial infections, little is known about the antigen specificity or the general development of effector and memory T-cell responses in hosts infected with protozoans. In this study we report on a wide-scale screen for the dominant parasite peptides recognized by CD8+ T cells in T.

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TcruziDB (http://TcruziDB.org) is an integrated post-genomics database for the parasitic organism, Trypanosoma cruzi, the causative agent of Chagas' disease. TcruziDB was established in 2003 as a flat-file database with tools for mining the unannotated sequence reads and preliminary contig assemblies emerging from the Tri-Tryp genome consortium (TIGR/SBRI/Karolinska).

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MS/MS and database searching has emerged as a valuable technology for rapidly analyzing protein expression, localization, and post-translational modifications. The probability-based search engine Mascot has found widespread use as a tool to correlate tandem mass spectra with peptides in a sequence database. Although the Mascot scoring algorithm provides a probability-based model for peptide identification, the independent peptide scores do not correlate with the significance of the proteins to which they match.

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TcruziDB (http://TcruziDB.org) is an integrated genome database for the parasitic organism Trypanosoma cruzi, the causative agent of Chagas' disease. The database currently incorporates all available sequence data (Genomic, BAC, EST) in a single user-friendly location.

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