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Elucidation of Host-Pathogen Interactions via Dual RNA-Seq Analysis to Support Development of Countermeasures Against the Intracellular Bacterial Pathogen Burkholderia pseudomallei

Branda, Steven B.; Wang, Pei-Li W.; LaBauve, Annette E.; Sinha, Anupama S.; Poorey, Kunal N.; Williams, Kelly P.; Michailidis, George M.; Schoeniger, Joseph S.; Mageeney, Catherine M.; Courtney, Colleen M.; El-Etr, Sahar E.; Franco, Magda F.; Lao, Victoria L.; D'haeseleer, Patrik D.; Pena, Jose P.; Segelke, Brent S.

Abstract not provided.

Ultrasensitive multi-species detection of CRISPR-Cas9 by a portable centrifugal microfluidic platform

Analytical Methods

Phaneuf, Christopher R.; Seamon, Kyle J.; Eckles, Tyler P.; Sinha, Anchal; Schoeniger, Joseph S.; Harmon, Brooke N.; Meagher, Robert M.; Abhyankar, Vinay V.; Koh, Chung-Yan K.

The discovery of the RNA-guided DNA nuclease CRISPR-Cas9 has enabled the targeted editing of genomes from diverse organisms, but the permanent and inheritable nature of genome modification also poses immense risks. The potential for accidental exposure, malicious use, or undesirable persistence of Cas9 therapeutics and off-target genome effects highlight the need for detection assays. Here we report a centrifugal microfluidic platform for the measurement of both Cas9 protein levels and nuclease activity. Because Cas9 from many bacterial species have been adapted for biotechnology applications, we developed the capability to detect Cas9 from the widely-used S. pyogenes, as well as S. aureus, N. meningitidis, and S. thermophilus using commercially-available antibodies. Further, we show that the phage-derived anti-CRISPR protein AcrIIC1, which binds to Cas9 from several species, can be used as a capture reagent to broaden the species range of detection. As genome modification generally requires Cas9 nuclease activity, a fluorescence-based sedimentation nuclease assay was also incorporated to allow the sensitive and simultaneous measurement of both Cas9 protein and activity in a single biological sample.

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Systematic and stochastic influences on the performance of the MinION nanopore sequencer across a range of nucleotide bias

Scientific Reports

Krishnakumar, Raga K.; Sinha, Anupama S.; Bird, Sara W.; Jayamohan, Harikrishnan; Edwards, Harrison S.; Schoeniger, Joseph S.; Patel, Kamlesh P.; Branda, Steven B.; Bartsch, Michael B.

Emerging sequencing technologies are allowing us to characterize environmental, clinical and laboratory samples with increasing speed and detail, including real-time analysis and interpretation of data. One example of this is being able to rapidly and accurately detect a wide range of pathogenic organisms, both in the clinic and the field. Genomes can have radically different GC content however, such that accurate sequence analysis can be challenging depending upon the technology used. Here, we have characterized the performance of the Oxford MinION nanopore sequencer for detection and evaluation of organisms with a range of genomic nucleotide bias. We have diagnosed the quality of base-calling across individual reads and discovered that the position within the read affects base-calling and quality scores. Finally, we have evaluated the performance of the current state-of-the-art neural network-based MinION basecaller, characterizing its behavior with respect to systemic errors as well as context- and sequence-specific errors. Overall, we present a detailed characterization the capabilities of the MinION in terms of generating high-accuracy sequence data from genomes with a wide range of nucleotide content. This study provides a framework for designing the appropriate experiments that are the likely to lead to accurate and rapid field-forward diagnostics.

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Real-Time Automated Pathogen Identification by Enhanced Ribotyping (RAPIER) LDRD Final Report

Bartsch, Michael B.; Bird, Sara W.; Branda, Steven B.; Edwards, Harrison E.; Jayamohan, Harikrishnan J.; Krishnakumar, Raga K.; Patel, Kamlesh P.; Schoeniger, Joseph S.; Sinha, Anupama S.

Funded through the IHNS/E&HS investment area for FY16-18, the RAPIER LDRD sought to evaluate the potential benefits and applicability of the new Oxford MinION nanopore sequencer to pathogen diagnostic applications in biodefense, biosurveillance, and global/public health. The project had four primary objectives: 1) to investigate the performance of the MinION sequencer while building facility with its operation, 2) to develop microfluidic library prep automation facilitating the use of the MinION in field-forward or point-of-care applications, 3) to leverage CRISPR/Cas9 technology to enable targeted identification of bacterial pathogens, and 4) to capitalize on the real- time data output capabilities of the MinION to enable rapid sequence-based diagnostics. While the rapid evolution of the MinION sequencing technology during the course of the project posed a number of challenges and required a reassessment of initial project priorities, it also provided unique opportunities, notably culminating in our development of the RUBRIC real-time selective sequencing software.

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Versatile High-Throughput Fluorescence Assay for Monitoring Cas9 Activity

Analytical Chemistry

Seamon, Kyle J.; Light, Yooli K.; Saada, Edwin A.; Schoeniger, Joseph S.; Harmon, Brooke N.

The RNA-guided DNA nuclease Cas9 is now widely used for the targeted modification of genomes of human cells and various organisms. Despite the extensive use of Clustered Regularly Interspaced Palindromic Repeats (CRISPR) systems for genome engineering and the rapid discovery and engineering of new CRISPR-associated nucleases, there are no high-throughput assays for measuring enzymatic activity. The current laboratory and future therapeutic uses of CRISPR technology have a significant risk of accidental exposure or clinical off-target effects, underscoring the need for therapeutically effective inhibitors of Cas9. Here, we develop a fluorescence assay for monitoring Cas9 nuclease activity and demonstrate its utility with S. pyogenes (Spy), S. aureus (Sau), and C. jejuni (Cje) Cas9. The assay was validated by quantitatively profiling the species specificity of published anti-CRISPR (Acr) proteins, confirming the reported inhibition of Spy Cas9 by AcrIIA4 and Cje Cas9 by AcrIIC1 and no inhibition of Sau Cas9 by either anti-CRISPR. To identify drug-like inhibitors, we performed a screen of 189 606 small molecules for inhibition of Spy Cas9. Of 437 hits (0.2% hit rate), six were confirmed as Cas9 inhibitors in a direct gel electrophoresis secondary assay. The high-throughput nature of this assay makes it broadly applicable for the discovery of additional Cas9 inhibitors or the characterization of Cas9 enzyme variants.

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Experimental single-strain mobilomics reveals events that shape pathogen emergence

Nucleic Acids Research

Schoeniger, Joseph S.; Hudson, Corey H.; Bent, Zachary W.; Sinha, Anupama S.; Williams, Kelly P.

Virulence genes on mobile DNAs such as genomic islands (GIs) and plasmids promote bacterial pathogen emergence. Excision is an early step in GI mobilization, producing a circular GI and a deletion site in the chromosome; circular forms are also known for some bacterial insertion sequences (ISs). The recombinant sequence at the junctions of such circles and deletions can be detected sensitively in high-throughput sequencing data, using new computational methods that enable empirical discovery of mobile DNAs. For the rich mobilome of a hospital Klebsiella pneumoniae strain, circularization junctions (CJs) were detected for six GIs and seven IS types. Our methods revealed differential biology of multiple mobile DNAs, imprecision of integrases and transposases, and differential activity among identical IS copies for IS26, ISKpn18 and ISKpn21. Using the resistance of circular dsDNA molecules to exonuclease, internally calibrated with the native plasmids, showed that not all molecules bearing GI CJs were circular. Transpositions were also detected, revealing replicon preference (ISKpn18 prefers a conjugative IncA/C2 plasmid), local action (IS26), regional preferences, selection (against capsule synthesis) and IS polarity inversion. Efficient discovery and global characterization of numerous mobile elements per experiment improves accounting for the new gene combinations that arise in emerging pathogens.

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Genome sequence of the historical clinical isolate Burkholderia pseudomallei PHLS 6

Genome Announcements

D'haeseleer, Patrik; Johnson, Shannon L.; Davenport, Karen W.; Chain, Patrick S.; Schoeniger, Joseph S.; Ray, Debjit R.; Sinha, Anupama S.; Williams, Kelly P.; Peña, José; Branda, Steven B.; El-Etr, Sahar

Here, we present the draft genome sequence of Burkholderia pseudomallei PHLS 6, a virulent clinical strain isolated from a melioidosis patient in Bangladesh in 1960. The draft genome consists of 39 contigs and is 7,322,181 bp long.

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Genomic Functionalization: The Next Revolution In Biology

Imbro, Paula I.; Schoeniger, Joseph S.; Anderson, Peter A.

We have implemented a ligand-alignment algorithm into our developed computational pipeline for identifying specificity-determining features (SDFs) in protein-ligand complexes. Given a set of protein-ligand complex structures, the algorithm aligns the complexes by ligand rather than by the C -RMSD or standard approach, providing a single reference frame for extracting SDFs. We anticipate that this ligand-alignment capability will be highly useful for protein function prediction. We already have a database containing > 20 K ligand-protein complex crystal structures taken from the Protein Data Bank. By aligning these proteins to single reference frames using ligand alignment, we can submit the complexes to our pipeline for SDF extraction. The SDFs derived from this training procedure can be used as thumbprints that are hallmarks of individual enzyme classes. These SDF thumbprints may then serve as guides to the prediction of function of new unknown proteins.

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A Microfluidic DNA Library Preparation Platform for Next-Generation Sequencing

PLoS ONE

Kim, Hanyoup; Jebrail, Mais J.; Sinha, Anupama S.; Bent, Zachary B.; Solberg, Owen D.; Williams, Kelly P.; Langevin, Stanley A.; Renzi, Ronald F.; Van De Vreugde, James L.; Meagher, Robert M.; Schoeniger, Joseph S.; Lane, Todd L.; Branda, Steven B.; Bartsch, Michael B.; Patel, Kamlesh D.

Next-generation sequencing (NGS) is emerging as a powerful tool for elucidating genetic information for a wide range of applications. Unfortunately, the surging popularity of NGS has not yet been accompanied by an improvement in automated techniques for preparing formatted sequencing libraries. To address this challenge, we have developed a prototype microfluidic system for preparing sequencer-ready DNA libraries for analysis by Illumina sequencing. Our system combines droplet-based digital microfluidic (DMF) sample handling with peripheral modules to create a fully-integrated, sample-in library-out platform. In this report, we use our automated system to prepare NGS libraries from samples of human and bacterial genomic DNA. E. coli libraries prepared on-device from 5 ng of total DNA yielded excellent sequence coverage over the entire bacterial genome, with >99% alignment to the reference genome, even genome coverage, and good quality scores. Furthermore, we produced a de novo assembly on a previously unsequenced multi-drug resistant Klebsiella pneumoniae strain BAA-2146 (KpnNDM). The new method described here is fast, robust, scalable, and automated. Our device for library preparation will assist in the integration of NGS technology into a wide variety of laboratories, including small research laboratories and clinical laboratories. © 2013 Kim et al.

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Characterization of Pathogens in Clinical Specimens via Suppression of Host Background for Efficient Second Generation Sequencing Analyses

Branda, Steven B.; Jebrail, Mais J.; Van De Vreugde, James L.; Langevin, Stanley A.; Bent, Zachary B.; Curtis, Deanna J.; Lane, Pamela L.; Carson, Bryan C.; La Bauve, Elisa L.; Patel, Kamlesh P.; Ricken, James B.; Schoeniger, Joseph S.; Solberg, Owen D.; Williams, Kelly P.; Misra, Milind; Powell, Amy J.; Pattengale, Nicholas D.; May, Elebeoba E.; Lane, Todd L.; Lindner, Duane L.; Young, Malin M.; VanderNoot, Victoria A.; Thaitrong, Numrin T.; Bartsch, Michael B.; Renzi, Ronald F.; Tran-Gyamfi, Mary B.; Meagher, Robert M.

Abstract not provided.

Copy of Automated Molecular Biology Platform Enabling Rapid & Efficient SGS Analysis of Pathogens in Clinical Samples

Branda, Steven B.; Jebrail, Mais J.; Van De Vreugde, James L.; Langevin, Stanley A.; Bent, Zachary B.; Curtis, Deanna J.; Lane, Pamela L.; Carson, Bryan C.; La Bauve, Elisa L.; Patel, Kamlesh P.; Ricken, James B.; Schoeniger, Joseph S.; Solberg, Owen D.; Williams, Kelly P.; Misra, Milind; Powell, Amy J.; Pattengale, Nicholas D.; May, Elebeoba E.; Lane, Todd L.; Lindner, Duane L.; Young, Malin M.; VanderNoot, Victoria A.; Thaitrong, Numrin T.; Bartsch, Michael B.; Renzi, Ronald F.; Tran-Gyamfi, Mary B.; Meagher, Robert M.

Abstract not provided.

Automated Molecular Biology Platform Enabling Rapid & Efficient SGS Analysis of Pathogens in Clinical Samples

Branda, Steven B.; Jebrail, Mais J.; Van De Vreugde, James L.; Langevin, Stanley A.; Bent, Zachary B.; Curtis, Deanna J.; Lane, Pamela L.; Carson, Bryan C.; La Bauve, Elisa L.; Patel, Kamlesh P.; Ricken, James B.; Schoeniger, Joseph S.; Solberg, Owen D.; Williams, Kelly P.; Misra, Milind; Powell, Amy J.; Pattengale, Nicholas D.; May, Elebeoba E.; Lane, Todd L.; Lindner, Duane L.; Young, Malin M.; VanderNoot, Victoria A.; Thaitrong, Numrin T.; Bartsch, Michael B.; Renzi, Ronald F.; Tran-Gyamfi, Mary B.; Meagher, Robert M.

Abstract not provided.

Results 1–50 of 79
Results 1–50 of 79