Medicine and Health Sciences Commons^™

Chimeric Systems Composed Of Swapped Tra Subunits Between Distantly-Related F Plasmids Reveal Striking Plasticity Among Type Iv Secretion Machines, Kouhei Kishida, Yang Grace Li, Natsumi Ogawa-Kishida, Pratick Khara, Abu Amar M Al Mamun, Rachel E Bosserman, Peter J Christie

Journal Articles

Bacterial type IV secretion systems (T4SSs) are a versatile family of macromolecular translocators, collectively able to recruit diverse DNA and protein substrates and deliver them to a wide range of cell types. Presently, there is little understanding of how T4SSs recognize substrate repertoires and form productive contacts with specific target cells. Although T4SSs are composed of a number of conserved subunits and adopt certain conserved structural features, they also display considerable compositional and structural diversity. Here, we explored the structural bases underlying the functional versatility of T4SSs through systematic deletion and subunit swapping between two conjugation systems encoded by the …

Chimeric Systems Composed Of Swapped Tra Subunits Between Distantly-Related F Plasmids Reveal Striking Plasticity Among Type Iv Secretion Machines, Kouhei Kishida, Yang Grace Li, Natsumi Ogawa-Kishida, Pratick Khara, Abu Amar M Al Mamun, Rachel E Bosserman, Peter J Christie

Journal Articles

Bacterial type IV secretion systems (T4SSs) are a versatile family of macromolecular translocators, collectively able to recruit diverse DNA and protein substrates and deliver them to a wide range of cell types. Presently, there is little understanding of how T4SSs recognize substrate repertoires and form productive contacts with specific target cells. Although T4SSs are composed of a number of conserved subunits and adopt certain conserved structural features, they also display considerable compositional and structural diversity. Here, we explored the structural bases underlying the functional versatility of T4SSs through systematic deletion and subunit swapping between two conjugation systems encoded by the …

Discovery And Clinical Proof-Of-Concept Of Rly-2608, A First-In-Class Mutant-Selective Allosteric Pi3kα Inhibitor That Decouples Antitumor Activity From Hyperinsulinemia, Andreas Varkaris, Ermira Pazolli, Hakan Gunaydin, Qi Wang, Levi Pierce, Alessandro A Boezio, Artemisa Bulku, Lucian Dipietro, Cary Fridrich, Adam Frost, Fabrizio Giordanetto, Erika P Hamilton, Katherine Harris, Michael Holliday, Tamieka L Hunter, Amanda Iskandar, Yongli Ji, Alexandre Larivée, Jonathan R Larochelle, André Lescarbeau, Fabien Llambi, Brenda Lormil, Mary M Mader, Brenton G Mar, Iain Martin, Thomas H Mclean, Klaus Michelsen, Yakov Pechersky, Erika Puente-Poushnejad, Kevin Raynor, Dipali Rogala, Ramin Samadani, Alison M Schram, Kelley Shortsleeves, Sweta Swaminathan, Shahein Tajmir, Gege Tan, Yong Tang, Roberto Valverde, Bryan Wehrenberg, Jeremy Wilbur, Bret R Williams, Hongtao Zeng, Hanmo Zhang, W Patrick Walters, Beni B Wolf, David E Shaw, Donald A Bergstrom, James Watters, James S Fraser, Pascal D Fortin, D Randal Kipp

Journal Articles

PIK3CA (PI3Kα) is a lipid kinase commonly mutated in cancer, including ∼40% of hormone receptor–positive breast cancer. The most frequently observed mutants occur in the kinase and helical domains. Orthosteric PI3Kα inhibitors suffer from poor selectivity leading to undesirable side effects, most prominently hyperglycemia due to inhibition of wild-type (WT) PI3Kα. Here, we used molecular dynamics simulations and cryo-electron microscopy to identify an allosteric network that provides an explanation for how mutations favor PI3Kα activation. A DNA-encoded library screen leveraging electron microscopy-optimized constructs, differential enrichment, and an orthosteric-blocking compound led to the identification of RLY-2608, a first-in-class allosteric mutant-selective inhibitor …

Vibrio Cyclitrophicus Phage Encoding Gene Transfer Agent Fragment, Representing A Novel Viral Family, Yao Xiong, Keran Ma, Xiao Zou, Yantao Liang, Kaiyang Zheng, Tiancong Wang, Hong Zhang, Yue Dong, Ziyue Wang, Yundan Liu, Hongbing Shao, Andrew Mcminn, Min Wang

Journal Articles

Vibrio is a prevalent bacterial genus in aquatic environments and exhibits diverse metabolic capabilities, playing a vital role in marine biogeochemical cycles. This study isolated a novel virus infecting Vibrio cyclitrophicus, vB_VviC_ZQ26, from coastal waters near Qingdao, China. The vB_VviC_ZQ26 comprises a linear double-stranded DNA genome with a length of 42,982 bp and a G + C content of 43.21 %, encoding 72 putative open reading frames (ORFs). Transmission electron microscope characterization indicates a siphoviral-morphology of vB_VviC_ZQ26. Nucleic-acids-wide analysis indicates a tetranucleotide frequency deviation for genomic segments encoding putative gene transfer agent protein (GTA) and coil-containing protein, implying divergent …

Illuminating Type Iv Secretion-Mediated Dna Trafficking Through Long Filaments, Peter J Christie

Journal Articles

No abstract provided.

Association Between Whole Blood-Derived Mitochondrial Dna Copy Number, Low-Density Lipoprotein Cholesterol, And Cardiovascular Disease Risk, Xue Liu, Xianbang Sun, Yuankai Zhang, Wenqing Jiang, Meng Lai, Kerri L Wiggins, Laura M Raffield, Lawrence F Bielak, Wei Zhao, Achilleas Pitsillides, Jeffrey Haessler, Yinan Zheng, Thomas W Blackwell, Jie Yao, Xiuqing Guo, Yong Qian, Bharat Thyagarajan, Nathan Pankratz, Stephen S Rich, Kent D Taylor, Patricia A Peyser, Susan R Heckbert, Sudha Seshadri, Eric Boerwinkle, Megan L Grove, Nicholas B Larson, Jennifer A Smith, Ramachandran S Vasan, Annette L Fitzpatrick, Myriam Fornage, Jun Ding, April P Carson, Goncalo Abecasis, Josée Dupuis, Alexander Reiner, Charles Kooperberg, Lifang Hou, Bruce M Psaty, James G Wilson, Daniel Levy, Jerome I Rotter, Joshua C Bis, Claudia L Satizabal, Dan E Arking, Chunyu Liu

Journal Articles

Background The relationship between mitochondrial DNA copy number (mtDNA CN) and cardiovascular disease remains elusive. Methods and Results We performed cross-sectional and prospective association analyses of blood-derived mtDNA CN and cardiovascular disease outcomes in 27 316 participants in 8 cohorts of multiple racial and ethnic groups with whole-genome sequencing. We also performed Mendelian randomization to explore causal relationships of mtDNA CN with coronary heart disease (CHD) and cardiometabolic risk factors (obesity, diabetes, hypertension, and hyperlipidemia).

Genome-Wide Analysis Of The Interplay Between Chromatin-Associated Rna And 3d Genome Organization In Human Cells, Riccardo Calandrelli, Xingzhao Wen, John Lalith Charles Richard, Zhifei Luo, Tri C Nguyen, Chien-Ju Chen, Zhijie Qi, Shuanghong Xue, Weizhong Chen, Zhangming Yan, Weixin Wu, Kathia Zaleta-Rivera, Rong Hu, Miao Yu, Yuchuan Wang, Wenbo Li, Jian Ma, Bing Ren, Sheng Zhong

Journal Articles

The interphase genome is dynamically organized in the nucleus and decorated with chromatin-associated RNA (caRNA). It remains unclear whether the genome architecture modulates the spatial distribution of caRNA and vice versa. Here, we generate a resource of genome-wide RNA-DNA and DNA-DNA contact maps in human cells. These maps reveal the chromosomal domains demarcated by locally transcribed RNA, hereafter termed RNA-defined chromosomal domains. Further, the spreading of caRNA is constrained by the boundaries of topologically associating domains (TADs), demonstrating the role of the 3D genome structure in modulating the spatial distribution of RNA. Conversely, stopping transcription or acute depletion of RNA …

Deleterious Heteroplasmic Mitochondrial Mutations Are Associated With An Increased Risk Of Overall And Cancer-Specific Mortality, Yun Soo Hong, Stephanie L Battle, Wen Shi, Daniela Puiu, Vamsee Pillalamarri, Jiaqi Xie, Nathan Pankratz, Nicole J Lake, Monkol Lek, Jerome I Rotter, Stephen S Rich, Charles Kooperberg, Alex P Reiner, Paul L Auer, Nancy Heard-Costa, Chunyu Liu, Meng Lai, Joanne M Murabito, Daniel Levy, Megan L Grove, Alvaro Alonso, Richard Gibbs, Shannon Dugan-Perez, Lukasz P Gondek, Eliseo Guallar, Dan E Arking

Journal Articles

Mitochondria carry their own circular genome and disruption of the mitochondrial genome is associated with various aging-related diseases. Unlike the nuclear genome, mitochondrial DNA (mtDNA) can be present at 1000 s to 10,000 s copies in somatic cells and variants may exist in a state of heteroplasmy, where only a fraction of the DNA molecules harbors a particular variant. We quantify mtDNA heteroplasmy in 194,871 participants in the UK Biobank and find that heteroplasmy is associated with a 1.5-fold increased risk of all-cause mortality. Additionally, we functionally characterize mtDNA single nucleotide variants (SNVs) using a constraint-based score, mitochondrial local constraint …

Unique Transcriptional Profiles Underlie Osteosarcomagenesis Driven By Different P53 Mutants, Dhruv Chachad, Lalit R Patel, Carlos Vera Recio, Rasoul Pourebrahim, Elizabeth M Whitley, Wenyi Wang, Xiaoping Su, An Xu, Dung-Fang Lee, Guillermina Lozano

Journal Articles

UNLABELLED: Missense mutations in the DNA binding domain of p53 are characterized as structural or contact mutations based on their effect on the conformation of the protein. These mutations show gain-of-function (GOF) activities, such as promoting increased metastatic incidence compared with p53 loss, often mediated by the interaction of mutant p53 with a set of transcription factors. These interactions are largely context specific. To understand the mechanisms by which p53 DNA binding domain mutations drive osteosarcoma progression, we created mouse models, in which either the p53 structural mutant p53R172H or the contact mutant p53R245W are expressed specifically in osteoblasts, yielding …

The Tardigrade Damage Suppressor Protein Dsup Promotes Dna Damage In Neurons, Rocio Diaz Escarcega, Abhijeet A Patil, Matthew D Meyer, Jose F Moruno-Manchon, Alexander D Silvagnoli, Louise D Mccullough, Andrey S Tsvetkov

Journal Articles

Tardigrades are microscopic invertebrates, which are capable of withstanding extreme environmental conditions, including high levels of radiation. A Tardigrade protein, Dsup (Damage Suppressor), protects the Tardigrade's DNA during harsh environmental stress and X-rays. When expressed in cancer cells, Dsup protects DNA from single- and double-strand breaks (DSBs) induced by radiation, increases survival of irradiated cells, and protects DNA from reactive oxygen species. These unusual properties of Dsup suggested that understanding how the protein functions may help in the design of small molecules that could protect humans during radiotherapy or space travel. Here, we investigated if Dsup is protective in cortical …

Association Of Mitochondrial Dna Copy Number With Brain Mri Markers And Cognitive Function: A Meta-Analysis Of Community-Based Cohorts, Yuankai Zhang, Xue Liu, Kerri L Wiggins, Nuzulul Kurniansyah, Xiuqing Guo, Amanda L Rodrigue, Wei Zhao, Lisa R Yanek, Scott M Ratliff, Achilleas Pitsillides, Juan Sebastian Aguirre Patiño, Tamar Sofer, Dan E Arking, Thomas R Austin, Alexa S Beiser, John Blangero, Eric Boerwinkle, Jan Bressler, Joanne E Curran, Lifang Hou, Timothy M Hughes, Sharon L R Kardia, Lenore J Launer, Daniel Levy, Thomas H Mosley, Ilya M Nasrallah, Stephen S Rich, Jerome I Rotter, Sudha Seshadri, Wassim Tarraf, Kevin A González, Vasan Ramachandran, Kristine Yaffe, Paul A Nyquist, Bruce M Psaty, Charles S Decarli, Jennifer A Smith, David C Glahn, Hector M González, Joshua C Bis, Myriam Fornage, Susan R Heckbert, Annette L Fitzpatrick, Chunyu Liu, Claudia L Satizabal

Journal Articles

BACKGROUND AND OBJECTIVES: Previous studies suggest that lower mitochondrial DNA (mtDNA) copy number (CN) is associated with neurodegenerative diseases. However, whether mtDNA CN in whole blood is related to endophenotypes of Alzheimer disease (AD) and AD-related dementia (AD/ADRD) needs further investigation. We assessed the association of mtDNA CN with cognitive function and MRI measures in community-based samples of middle-aged to older adults.

METHODS: We included dementia-free participants from 9 diverse community-based cohorts with whole-genome sequencing in the Trans-Omics for Precision Medicine (TOPMed) program. Circulating mtDNA CN was estimated as twice the ratio of the average coverage of mtDNA to nuclear …

Lipid Surfaces And Glutamate Anions Enhance Formation Of Dynamic Biomolecular Condensates Containing Bacterial Cell Division Protein Ftsz And Its Dna-Bound Regulator Slma, Gianfranco Paccione, Miguel Á Robles-Ramos, Carlos Alfonso, Marta Sobrinos-Sanguino, William Margolin, Silvia Zorrilla, Begoña Monterroso, Germán Rivas

Journal Articles

Dynamic biomolecular condensates formed by liquid-liquid phase separation can regulate the spatial and temporal organization of proteins, thus modulating their functional activity in cells. Previous studies showed that the cell division protein FtsZ from Escherichia coli formed dynamic phase-separated condensates with nucleoprotein complexes containing the FtsZ spatial regulator SlmA under crowding conditions, with potential implications for condensate-mediated spatiotemporal control of FtsZ activity in cell division. In the present study, we assessed formation of these condensates in the presence of lipid surfaces and glutamate ions to better approximate the E. coli intracellular environment. We found that potassium glutamate substantially promoted the …

Overlapping And Distinct Functions Of The Paralogous Pagr Regulators Of Bacillus Anthracis, Ileana D Corsi, Theresa M Koehler

Journal Articles

The Bacillus anthracis pagA gene, encoding the protective antigen component of anthrax toxin, is part of a bicistronic operon on pXO1 that codes for its own repressor, PagR1. In addition to the pagAR1 operon, PagR1 regulates sap and eag, two chromosome genes encoding components of the surface layer, a mounting structure for surface proteins involved in virulence. Genomic studies have revealed a PagR1 paralog, PagR2, encoded by a gene on pXO2. The amino acid sequences of the paralogues are 71% identical and show similarity to the ArsR family of transcription regulators. We determined that the expression of either rPagR1 …

A Nickase Cas9 Gene-Drive System Promotes Super-Mendelian Inheritance In Drosophila, Víctor López Del Amo, Sara Sanz Juste, Valentino M Gantz

Journal Articles

CRISPR-based gene-drives have been proposed for managing insect populations, including disease-transmitting mosquitoes, due to their ability to bias their inheritance toward super-Mendelian rates (>50%). Current technologies use a Cas9 that introduces DNA double-strand breaks into the opposing wild-type allele to replace it with a copy of the gene-drive allele via DNA homology-directed repair. However, the use of different Cas9 versions is unexplored, and alternative approaches could increase the available toolkit for gene-drive designs. Here, we report a gene-drive that relies on Cas9 nickases that generate staggered paired nicks in DNA to propagate the engineered gene-drive cassette. We show that …

Nanog Prion-Like Assembly Mediates Dna Bridging To Facilitate Chromatin Reorganization And Activation Of Pluripotency, Kyoung-Jae Choi, My Diem Quan, Chuangye Qi, Joo-Hyung Lee, Phoebe S Tsoi, Mahla Zahabiyon, Aleksandar Bajic, Liya Hu, B V Venkataram Prasad, Shih-Chu Jeff Liao, Wenbo Li, Allan Chris M Ferreon, Josephine C Ferreon

Journal Articles

Human NANOG expression resets stem cells to ground-state pluripotency. Here we identify the unique features of human NANOG that relate to its dose-sensitive function as a master transcription factor. NANOG is largely disordered, with a C-terminal prion-like domain that phase-transitions to gel-like condensates. Full-length NANOG readily forms higher-order oligomers at low nanomolar concentrations, orders of magnitude lower than typical amyloids. Using single-molecule Förster resonance energy transfer and fluorescence cross-correlation techniques, we show that NANOG oligomerization is essential for bridging DNA elements in vitro. Using chromatin immunoprecipitation sequencing and Hi-C 3.0 in cells, we validate that NANOG prion-like domain assembly is …

Epigenome-Wide Association Study Of Mitochondrial Genome Copy Number, Penglong Wang, Christina A Castellani, Jie Yao, Tianxiao Huan, Lawrence F Bielak, Wei Zhao, Jeffrey Haessler, Roby Joehanes, Xianbang Sun, Xiuqing Guo, Ryan J Longchamps, Joann E Manson, Megan L Grove, Jan Bressler, Kent D Taylor, Tuuli Lappalainen, Silva Kasela, David J Van Den Berg, Lifang Hou, Alexander Reiner, Yongmei Liu, Eric Boerwinkle, Jennifer A Smith, Patricia A Peyser, Myriam Fornage, Stephen S Rich, Jerome I Rotter, Charles Kooperberg, Dan E Arking, Daniel Levy, Chunyu Liu

Journal Articles

We conducted cohort- and race-specific epigenome-wide association analyses of mitochondrial deoxyribonucleic acid (mtDNA) copy number (mtDNA CN) measured in whole blood from participants of African and European origins in five cohorts (n = 6182, mean age = 57-67 years, 65% women). In the meta-analysis of all the participants, we discovered 21 mtDNA CN-associated DNA methylation sites (CpG) (P < 1 × 10-7), with a 0.7-3.0 standard deviation increase (3 CpGs) or decrease (18 CpGs) in mtDNA CN corresponding to a 1% increase in DNA methylation. Several significant CpGs have been reported to be associated with at least two risk factors (e.g. chronological age or smoking) for cardiovascular disease (CVD). Five genes [PR/SET domain 16, nuclear receptor subfamily 1 group H member 3 (NR1H3), DNA repair protein, DNA polymerase kappa and decaprenyl-diphosphate synthase subunit 2], which harbor nine significant CpGs, are known to be involved in mitochondrial biosynthesis and functions. For example, NR1H3 encodes a transcription factor that is differentially expressed during an adipose tissue transition. The methylation level of cg09548275 in NR1H3 was negatively associated with mtDNA CN (effect size = -1.71, P = 4 × 10-8) and was positively associated with the NR1H3 expression level (effect size = 0.43, P = 0.0003), which indicates that the methylation level in NR1H3 may underlie the relationship between mtDNA CN, the NR1H3 transcription factor and energy expenditure. In summary, the study results suggest that mtDNA CN variation in whole blood is associated with DNA methylation levels in genes that are involved in a wide range of mitochondrial activities. These findings will help reveal molecular mechanisms between mtDNA CN and CVD.

The Impact Of The Th17:Treg Axis On The Iga-Biome Across The Glycemic Spectrum, Heather T Essigmann, Kristi L Hoffman, Joseph F Petrosino, Goo Jun, David Aguilar, Craig L Hanis, Herbert L Dupont, Eric L Brown

Journal Articles

Secretory IgA (SIgA) is released into mucosal surfaces where its function extends beyond that of host defense to include the shaping of resident microbial communities by mediating exclusion/inclusion of respective microbes and regulating bacterial gene expression. In this capacity, SIgA acts as the fulcrum on which host immunity and the health of the microbiota are balanced. We recently completed an analysis of the gut and salivary IgA-Biomes (16S rDNA sequencing of SIgA-coated/uncoated bacteria) in Mexican-American adults that identified IgA-Biome differences across the glycemic spectrum. As Th17:Treg ratio imbalances are associated with gut microbiome dysbiosis and chronic inflammatory conditions such as …

Evaluation Of Mitochondrial Dna Copy Number Estimation Techniques, Ryan J Longchamps, Christina A Castellani, Stephanie Y Yang, Charles E Newcomb, Jason A Sumpter, John Lane, Megan L Grove, Eliseo Guallar, Nathan Pankratz, Kent D Taylor, Jerome I Rotter, Eric Boerwinkle, Dan E Arking

Journal Articles

Mitochondrial DNA copy number (mtDNA-CN), a measure of the number of mitochondrial genomes per cell, is a minimally invasive proxy measure for mitochondrial function and has been associated with several aging-related diseases. Although quantitative real-time PCR (qPCR) is the current gold standard method for measuring mtDNA-CN, mtDNA-CN can also be measured from genotyping microarray probe intensities and DNA sequencing read counts. to conduct a comprehensive examination on the performance of these methods, we use known mtDNA-CN correlates (age, sex, white blood cell count, Duffy locus genotype, incident cardiovascular disease) to evaluate mtDNA-CN calculated from qPCR, two microarray platforms, as well …

Exome Sequencing Identifies Gene Variants And Networks Associated With Extreme Respiratory Outcomes Following Preterm Birth, Aaron Hamvas, Rui Feng, Yingtao Bi, Fan Wang, Soumyaroop Bhattacharya, Jared Mereness, Madhurima Kaushal, C Michael Cotten, Philip L Ballard, Thomas J Mariani

Journal Articles

BACKGROUND: Previous studies have identified genetic variants associated with bronchopulmonary dysplasia (BPD) in extremely preterm infants. However, findings with genome-wide significance have been rare, and not replicated. We hypothesized that whole exome sequencing (WES) of premature subjects with extremely divergent phenotypic outcomes could facilitate the identification of genetic variants or gene networks contributing disease risk.

RESULTS: The Prematurity and Respiratory Outcomes Program (PROP) recruited a cohort of > 765 extremely preterm infants for the identification of markers of respiratory morbidity. We completed WES on 146 PROP subjects (85 affected, 61 unaffected) representing extreme phenotypes of early respiratory morbidity. We tested for …

Large-Scale Identification Of Chemically Induced Mutations In Drosophila Melanogaster., Nele A Haelterman, Lichun Jiang, Yumei Li, Vafa Bayat, Hector Sandoval, Berrak Ugur, Kai Li Tan, Ke Zhang, Danqing Bei, Bo Xiong, Wu-Lin Charng, Theodore Busby, Adeel Jawaid, Gabriela David, Manish Jaiswal, Koen J T Venken, Shinya Yamamoto, Rui Chen, Hugo J Bellen

Faculty Publications

Forward genetic screens using chemical mutagens have been successful in defining the function of thousands of genes in eukaryotic model organisms. The main drawback of this strategy is the time-consuming identification of the molecular lesions causative of the phenotypes of interest. With whole-genome sequencing (WGS), it is now possible to sequence hundreds of strains, but determining which mutations are causative among thousands of polymorphisms remains challenging. We have sequenced 394 mutant strains, generated in a chemical mutagenesis screen, for essential genes on the Drosophila X chromosome and describe strategies to reduce the number of candidate mutations from an average of …

Mitochondrial Cardiomyopathy: Pathophysiology, Diagnosis, And Management, Deborah E Meyers, Haseeb Ilias Basha, Mary Kay Koenig

The Texas Heart Institute Journal

Mitochondrial disease is a heterogeneous group of multisystemic diseases that develop consequent to mutations in nuclear or mitochondrial DNA. The prevalence of inherited mitochondrial disease has been estimated to be greater than 1 in 5,000 births; however, the diagnosis and treatment of this disease are not taught in most adult-cardiology curricula. Because mitochondrial diseases often occur as a syndrome with resultant multiorgan dysfunction, they might not immediately appear to be specific to the cardiovascular system. Mitochondrial cardiomyopathy can be described as a myocardial condition characterized by abnormal heart-muscle structure, function, or both, secondary to genetic defects involving the mitochondrial respiratory …

Molecular Mechanism By Which The Nucleoid Occlusion Factor, Slma, Keeps Cytokinesis In Check, Nam Ky Tonthat, Stefan T Arold, Brian F Pickering, Michael W Van Dyke, Shoudan Liang, Yue Lu, Tushar K Beuria, William Margolin, Maria A Schumacher

Journal Articles

In Escherichia coli, cytokinesis is orchestrated by FtsZ, which forms a Z-ring to drive septation. Spatial and temporal control of Z-ring formation is achieved by the Min and nucleoid occlusion (NO) systems. Unlike the well-studied Min system, less is known about the anti-DNA guillotining NO process. Here, we describe studies addressing the molecular mechanism of SlmA (synthetic lethal with a defective Min system)-mediated NO. SlmA contains a TetR-like DNA-binding fold, and chromatin immunoprecipitation analyses show that SlmA-binding sites are dispersed on the chromosome except the Ter region, which segregates immediately before septation. SlmA binds DNA and FtsZ simultaneously, and the …

Hla-Dpb1 And Dpb2 Are Genetic Loci For Systemic Sclerosis: A Genome-Wide Association Study In Koreans With Replication In North Americans, Xiaodong Zhou, Jong Eun Lee, Frank C Arnett, Momiao Xiong, Min Young Park, Yeon Kyeong Yoo, Eun Soon Shin, John D Reveille, Maureen D Mayes, Jin Hyun Kim, Ran Song, Ji Yong Choi, Ji Ah Park, Yun Jong Lee, Eun Young Lee, Yeong Wook Song, Eun Bong Lee

Journal Articles

OBJECTIVE: To identify systemic sclerosis (SSc) susceptibility loci via a genome-wide association study.

METHODS: A genome-wide association study was performed in 137 patients with SSc and 564 controls from Korea using the Affymetrix Human SNP Array 5.0. After fine-mapping studies, the results were replicated in 1,107 SSc patients and 2,747 controls from a US Caucasian population.

RESULTS: The single-nucleotide polymorphisms (SNPs) (rs3128930, rs7763822, rs7764491, rs3117230, and rs3128965) of HLA-DPB1 and DPB2 on chromosome 6 formed a distinctive peak with log P values for association with SSc susceptibility (P=8.16x10(-13)). Subtyping analysis of HLA-DPB1 showed that DPB1*1301 (P=7.61x10(-8)) and DPB1*0901 (P=2.55x10(-5)) were …

The Performance Of Human Papillomavirus High-Risk Dna Testing In The Screening And Diagnostic Settings, Marylou Cárdenas-Turanzas, Graciela M Nogueras-Gonzalez, Michael E Scheurer, Karen Adler-Storthz, J L Benedet, J Robert Beck, Michele Follen, Scott B Cantor

Journal Articles

OBJECTIVE: We sought to evaluate the performance of the human papillomavirus high-risk DNA test in patients 30 years and older.

MATERIALS AND METHODS: Screening (n=835) and diagnosis (n=518) groups were defined based on prior Papanicolaou smear results as part of a clinical trial for cervical cancer detection. We compared the Hybrid Capture II (HCII) test result with the worst histologic report. We used cervical intraepithelial neoplasia (CIN) 2/3 or worse as the reference of disease. We calculated sensitivities, specificities, positive and negative likelihood ratios (LR+ and LR-), receiver operating characteristic (ROC) curves, and areas under the ROC curves for the …

Identification And Phenotypic Characterization Of A Second Collagen Adhesin, Scm, And Genome-Based Identification And Analysis Of 13 Other Predicted Mscramms, Including Four Distinct Pilus Loci, In Enterococcus Faecium, Jouko Sillanpää, Sreedhar R Nallapareddy, Vittal P Prakash, Xiang Qin, Magnus Höök, George M Weinstock, Barbara E Murray

Journal Articles

Attention has recently been drawn to Enterococcus faecium because of an increasing number of nosocomial infections caused by this species and its resistance to multiple antibacterial agents. However, relatively little is known about the pathogenic determinants of this organism. We have previously identified a cell-wall-anchored collagen adhesin, Acm, produced by some isolates of E. faecium, and a secreted antigen, SagA, exhibiting broad-spectrum binding to extracellular matrix proteins. Here, we analysed the draft genome of strain TX0016 for potential microbial surface components recognizing adhesive matrix molecules (MSCRAMMs). Genome-based bioinformatics identified 22 predicted cell-wall-anchored E. faecium surface proteins (Fms), of which 15 …

A Functional Collagen Adhesin Gene, Acm, In Clinical Isolates Of Enterococcus Faecium Correlates With The Recent Success Of This Emerging Nosocomial Pathogen, Sreedhar R Nallapareddy, Kavindra V Singh, Pablo C Okhuysen, Barbara E Murray

Journal Articles

Enterococcus faecium recently evolved from a generally avirulent commensal into a multidrug-resistant health care-associated pathogen causing difficult-to-treat infections, but little is known about the factors responsible for this change. We previously showed that some E. faecium strains express a cell wall-anchored collagen adhesin, Acm. Here we analyzed 90 E. faecium isolates (99% acm(+)) and found that the Acm protein was detected predominantly in clinically derived isolates, while the acm gene was present as a transposon-interrupted pseudogene in 12 of 47 isolates of nonclinical origin. A highly significant association between clinical (versus fecal or food) origin and collagen adherence (P

Pcr-Based Assay Using Occult Blood Detection Cards For Detection Of Diarrheagenic Escherichia Coli In Specimens From Us Travelers To Mexico With Acute Diarrhea, Kevin A Grimes, Jamal A Mohamed, Herbert L Dupont, Ranjit S Padda, Zhi-Dong Jiang, Jose Flores, Jaime Belkind-Gerson, Francisco G Martinez-Sandoval, Pablo C Okhuysen

Journal Articles

Large field studies of travelers' diarrhea for multiple destinations are limited by the need to perform stool cultures on site in a timely manner. A method for the collection, transport, and storage of fecal specimens that does not require immediate processing and refrigeration and that is stable for months would be advantageous. This study was designed to determine if enterotoxigenic Escherichia coli (ETEC) and enteroaggregative E. coli (EAEC) DNA could be identified from cards that were processed for the evaluation of fecal occult blood. U.S. students traveling to Mexico during 2005 to 2007 were monitored for the occurrence of diarrheal …

Water-Soluble Fullerene (C60) Derivatives As Nonviral Gene-Delivery Vectors, Balaji Sitharaman, Tatiana Y Zakharian, Anita Saraf, Preeti Misra, Jared Ashcroft, Su Pan, Quynh P Pham, Antonios G Mikos, Lon J Wilson, David A Engler

Journal Articles

A new class of water-soluble C60 transfecting agents has been prepared using Hirsch-Bingel chemistry and assessed for their ability to act as gene-delivery vectors in vitro. In an effort to elucidate the relationship between the hydrophobicity of the fullerene core, the hydrophilicity of the water-solubilizing groups, and the overall charge state of the C60 vectors in gene delivery and expression, several different C60 derivatives were synthesized to yield either positively charged, negatively charged, or neutral chemical functionalities under physiological conditions. These fullerene derivatives were then tested for their ability to transfect cells grown in culture with DNA carrying the green …

Enterococcus Faecalis Pcfc, A Spatially Localized Substrate Receptor For Type Iv Secretion Of The Pcf10 Transfer Intermediate, Yuqing Chen, Xiaolin Zhang, Dawn Manias, Hye-Jeong Yeo, Gary M Dunny, Peter J Christie

Journal Articles

Upon sensing of peptide pheromone, Enterococcus faecalis efficiently transfers plasmid pCF10 through a type IV secretion (T4S) system to recipient cells. The PcfF accessory factor and PcfG relaxase initiate transfer by catalyzing strand-specific nicking at the pCF10 origin of transfer sequence (oriT). Here, we present evidence that PcfF and PcfG spatially coordinate docking of the pCF10 transfer intermediate with PcfC, a membrane-bound putative ATPase related to the coupling proteins of gram-negative T4S machines. PcfC and PcfG fractionated with the membrane and PcfF with the cytoplasm, yet all three proteins formed several punctate foci at the peripheries of pheromone-induced cells as …

Large Scale Variation In Enterococcus Faecalis Illustrated By The Genome Analysis Of Strain Og1rf, Agathe Bourgogne, Danielle A Garsin, Xiang Qin, Kavindra V Singh, Jouko Sillanpaa, Shailaja Yerrapragada, Yan Ding, Shannon Dugan-Rocha, Christian Buhay, Hua Shen, Guan Chen, Gabrielle Williams, Donna Muzny, Arash Maadani, Kristina A Fox, Jason Gioia, Lei Chen, Yue Shang, Cesar A Arias, Sreedhar R Nallapareddy, Meng Zhao, Vittal P Prakash, Shahreen Chowdhury, Huaiyang Jiang, Richard A Gibbs, Barbara E Murray, Sarah K Highlander, George M Weinstock

Journal Articles

BACKGROUND: Enterococcus faecalis has emerged as a major hospital pathogen. To explore its diversity, we sequenced E. faecalis strain OG1RF, which is commonly used for molecular manipulation and virulence studies.

RESULTS: The 2,739,625 base pair chromosome of OG1RF was found to contain approximately 232 kilobases unique to this strain compared to V583, the only publicly available sequenced strain. Almost no mobile genetic elements were found in OG1RF. The 64 areas of divergence were classified into three categories. First, OG1RF carries 39 unique regions, including 2 CRISPR loci and a new WxL locus. Second, we found nine replacements where a sequence …