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A Cotransformation Method To Identify A Restriction-Modification Enzyme That Reduces Conjugation Efficiency In Campylobacter Jejuni, Ximin Zeng, Zuowei Wu, Qijing Zhang, Jun Lin Dec 2018

A Cotransformation Method To Identify A Restriction-Modification Enzyme That Reduces Conjugation Efficiency In Campylobacter Jejuni, Ximin Zeng, Zuowei Wu, Qijing Zhang, Jun Lin

Veterinary Microbiology and Preventive Medicine Publications

Conjugation is an important mechanism for horizontal gene transfer in Campylobacter jejuni, the leading cause of human bacterial gastroenteritis in developed countries. However, to date, the factors that significantly influence conjugation efficiency in Campylobacter spp. are still largely unknown. Given that multiple recombinant loci could independently occur within one recipient cell during natural transformation, the genetic materials from a high-frequency conjugation (HFC) C. jejuni strain may be cotransformed with a selection marker into a low-frequency conjugation (LFC) recipient strain, creating new HFC transformants suitable for the identification of conjugation factors using a comparative genomics approach. To test this, an erythromycin ...


Heterogeneous And Flexible Transmission Of Mcr-1 In Hospital-Associated Escherichia Coli, Yingbo Shen, Zuowei Wu, Yang Wang, Rong Zhang, Hong-Wei Zhou, Shaolin Wang, Lei Lei, Mei Li, Jiachang Cai, Jonathan Tyrrell, Guo-Bao Tian, Congming Wu, Qijing Zhang, Jianzhong Shen, Timothy R. Walsh, Zhangqi Shen Jan 2018

Heterogeneous And Flexible Transmission Of Mcr-1 In Hospital-Associated Escherichia Coli, Yingbo Shen, Zuowei Wu, Yang Wang, Rong Zhang, Hong-Wei Zhou, Shaolin Wang, Lei Lei, Mei Li, Jiachang Cai, Jonathan Tyrrell, Guo-Bao Tian, Congming Wu, Qijing Zhang, Jianzhong Shen, Timothy R. Walsh, Zhangqi Shen

Veterinary Microbiology and Preventive Medicine Publications

The recent emergence of a transferable colistin resistance mechanism, MCR-1, has gained global attention because of its threat to clinical treatment of infections caused by multidrug-resistant Gram-negative bacteria. However, the possible transmission route of mcr-1 among Enterobacteriaceae species in clinical settings is largely unknown. Here, we present a comprehensive genomic analysis of Escherichia coli isolates collected in a hospital in Hangzhou, China. We found that mcr-1-carrying isolates from clinical infections and feces of inpatients and healthy volunteers were genetically diverse and were not closely related phylogenetically, suggesting that clonal expansion is not involved in the spread of mcr-1. The ...


A Mutator Phenotype Promoting The Emergence Of Spontaneous Oxidative Stress-Resistant Mutants In Campylobacter Jejuni, Lei Dai, Orhan Sahin, Yizhi Tang, Qijing Zhang Dec 2017

A Mutator Phenotype Promoting The Emergence Of Spontaneous Oxidative Stress-Resistant Mutants In Campylobacter Jejuni, Lei Dai, Orhan Sahin, Yizhi Tang, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

Campylobacter jejuni is a leading cause of foodborne illnesses worldwide. As a microaerophilic organism, C. jejuni must be able to defend against oxidative stress encountered both in the host and in the environment. How Campylobacter utilizes a mutation-based mechanism for adaptation to oxidative stress is still unknown. Here we present a previously undescribed phenotypic and genetic mechanism that promotes the emergence of oxidative stress resistant mutants. Specifically, we showed that a naturally occurring mutator phenotype, resulting from a loss of function mutation in the DNA repair enzyme MutY, increased oxidative stress resistance (OXR) in C. jejuni. We further demonstrated ...


Efflux Pump Overexpression Contributes To Tigecycline Heteroresistance In Salmonella Enterica Serovar Typhimurium, Yi Chen, Daxing Hu, Qijing Zhang, Xiao-Ping Liao, Ya-Hong Liu, Jian Sun Feb 2017

Efflux Pump Overexpression Contributes To Tigecycline Heteroresistance In Salmonella Enterica Serovar Typhimurium, Yi Chen, Daxing Hu, Qijing Zhang, Xiao-Ping Liao, Ya-Hong Liu, Jian Sun

Veterinary Microbiology and Preventive Medicine Publications

Bacterial heteroresistance has been identified in several combinations of bacteria and antibiotics, and it complicated the therapeutic strategies. Tigecycline is being used as one of the optimal options for the treatment of infections caused by multidrug-resistant Salmonella. This study investigated whether heterorresistance to tigecycline exists in a Salmonella enterica serovar Typhimurium strain harboring the oqxAB-bearing IncHI2 plasmid pHXY0908. MIC and population analyses were performed to evaluate population-wide susceptibility to tigecycline. The effects of efflux pumps on MIC levels were assessed using the efflux pump inhibitor Phe-Arg-β-naphthylamide, measuring intracellular tigecycline accumulation as well as mRNA levels of regulatory and efflux ...


Genomic Insights Into Campylobacter Jejuni Virulence And Population Genetics, Zuowei Wu, Kathy Mou, Orhan Sahin, Qijing Zhang Jan 2016

Genomic Insights Into Campylobacter Jejuni Virulence And Population Genetics, Zuowei Wu, Kathy Mou, Orhan Sahin, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

Campylobacter jejuni has long been recognized as a main food-borne pathogen in many parts of the world. Natural reservoirs include a wide variety of domestic and wild birds and mammals, whose intestines offer a suitable biological niche for the survival and dissemination of the organism. Understanding the genetic basis of the biology and pathogenicity of C. jejuni is vital to prevent and control Campylobacter-associated infections. The recent progress in sequencing techniques has allowed for a rapid increase in our knowledge of the molecular biology and the genetic structures of Campylobacter. Single-molecule realtime (SMRT) sequencing, which goes beyond four-base sequencing ...


Emergence Of Extensively Drug-Resistant Proteus Mirabilis Harboring A Conjugative Ndm-1 Plasmid And A Novel Salmonella Genomic Island 1 Variant, Sgi1-Z, Shangshang Qin, Hui Qi, Qijing Zhang, Di Zhao, Zhen-Zhen Liu, Hao Tian, Lijuan Xu, Hui Xu, Mengmeng Zhou, Xianju Feng, Hong-Min Liu Oct 2015

Emergence Of Extensively Drug-Resistant Proteus Mirabilis Harboring A Conjugative Ndm-1 Plasmid And A Novel Salmonella Genomic Island 1 Variant, Sgi1-Z, Shangshang Qin, Hui Qi, Qijing Zhang, Di Zhao, Zhen-Zhen Liu, Hao Tian, Lijuan Xu, Hui Xu, Mengmeng Zhou, Xianju Feng, Hong-Min Liu

Veterinary Microbiology and Preventive Medicine Publications

Acquisition of blaNDM-1 in bacterial species, such as Proteus mirabilis that is intrinsically resistant to tetracycline, tigecycline and colistin, will make clinical treatment extremely difficult. Here, we characterized an NDM-1-producing clinical isolate of P. mirabilis (PM58) that displayed an extensively drug-resistant (XDR) phenotype, susceptible only to aztreonam. Molecular analysis revealed that PM58 harbored both a conjugative NDM-1 plasmid and a novel Salmonella genomic island 1 variant on chromosome.


Constitutive And Inducible Expression Of The Rrna Methylase Gene Erm(B) In Campylobacter, Fengru Deng, Jianzhong Shen, Maojun Zhang, Congming Wu, Qijing Zhang, Yang Wang Oct 2015

Constitutive And Inducible Expression Of The Rrna Methylase Gene Erm(B) In Campylobacter, Fengru Deng, Jianzhong Shen, Maojun Zhang, Congming Wu, Qijing Zhang, Yang Wang

Veterinary Microbiology and Preventive Medicine Publications

Macrolides are the antimicrobials of choice for treating human campylobacteriosis. The recent emergence of erm(B) in Campylobacter bacteria threatens the utility of this class of antibiotics. Here we report the constitutive and inducible expression of erm(B) in Campylobacter isolates derived from diarrheal patients and food-producing animals. Constitutive expression of erm(B) was associated with insertion and deletion in the regulatory region of the gene, providing the first documentation of the differential expression of erm(B) in Campylobacter bacteria.


Genetic Basis And Functional Consequences Of Differential Expression Of The Cmeabc Efflux Pump In Campylobacter Jejuni Isolates, Tara Grinnage-Pulley, Qijing Zhang Jul 2015

Genetic Basis And Functional Consequences Of Differential Expression Of The Cmeabc Efflux Pump In Campylobacter Jejuni Isolates, Tara Grinnage-Pulley, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

The CmeABC multidrug efflux transporter of Campylobacter jejuni plays a key role in antimicrobial resistance and is suppressed by CmeR, a transcriptional regulator of the TetR family. Overexpression of CmeABC has been observed in laboratory-generated mutants, but it is unknown if this phenotype occurs naturally in C. jejuni isolates and if it has any functional consequences. To answer these questions, expression of cmeABC in natural isolates obtained from broiler chickens, turkeys and humans was examined, and the genetic mechanisms and role of cmeABC differential expression in antimicrobial resistance was determined. Among the 64 C. jejuni isolates examined in this study ...


Livestock Models In Translational Medicine, James A. Roth, Christopher K. Tuggle Jan 2015

Livestock Models In Translational Medicine, James A. Roth, Christopher K. Tuggle

Veterinary Microbiology and Preventive Medicine Publications

This issue of the ILAR Journal focuses on livestock models in translational medicine. Livestock models of selected human diseases present important advantages as compared with rodent models for translating fundamental breakthroughs in biology to useful preventatives and therapeutics for humans. Livestock reflect the complexity of applying medical advances in an outbred species. In many cases, the pathogenesis of infectious, metabolic, genetic, and neoplastic diseases in livestock species more closely resembles that in humans than does the pathogenesis of rodent models. Livestock models also provide the advantage of similar organ size and function and the ability to serially sample an animal ...


Emergence Of Multidrug-Resistant Campylobacter Species Isolates With A Horizontally Acquired Rrna Methylase, Yang Wang, Maojun Zhang, Fengru Deng, Zhangqi Shen, Congming Wu, Jianzhong Zhang, Qijing Zhang, Jianzhong Shen Sep 2014

Emergence Of Multidrug-Resistant Campylobacter Species Isolates With A Horizontally Acquired Rrna Methylase, Yang Wang, Maojun Zhang, Fengru Deng, Zhangqi Shen, Congming Wu, Jianzhong Zhang, Qijing Zhang, Jianzhong Shen

Veterinary Microbiology and Preventive Medicine Publications

Antibiotic-resistant Campylobacter constitutes a serious threat to public health, and resistance to macrolides is of particular concern, as this class of antibiotics is the drug of choice for clinical therapy of campylobacteriosis. Very recently, a horizontally transferrable macrolide resistance mediated by the rRNA methylase gene erm(B) was reported in a Campylobacter coli isolate, but little is known about the dissemination of erm(B) among Campylobacter isolates and the association of erm(B)-carrying isolates with clinical disease. To address this question and facilitate the control of antibiotic-resistant Campylobacter, we determined the distribution of erm(B) in 1,554 C ...


High Incidence And Endemic Spread Of Ndm-1-Positive Enterobacteriaceae In Henan Province, China, Shangshang Qin, Ying Fu, Qijing Zhang, Hui Qi, Jian Guo Wen, Hui Xu, Lijuan Xu, Li Zeng, Hao Tian, Lijuan Rong, Yonghong Li, Lihong Shan, Hongde Xu, Yunsong Yu, Xianju Feng, Hong-Min Liu Aug 2014

High Incidence And Endemic Spread Of Ndm-1-Positive Enterobacteriaceae In Henan Province, China, Shangshang Qin, Ying Fu, Qijing Zhang, Hui Qi, Jian Guo Wen, Hui Xu, Lijuan Xu, Li Zeng, Hao Tian, Lijuan Rong, Yonghong Li, Lihong Shan, Hongde Xu, Yunsong Yu, Xianju Feng, Hong-Min Liu

Veterinary Microbiology and Preventive Medicine Publications

The emergence and spread of New Delhi metallo-β-lactamase 1 (NDM-1)-producing carbapenem-resistant Enterobacteriaceae (CRE) present an urgent threat to human health. In China, the blaNDM-1 gene has been reported mostly in Acinetobacter spp. but is rarely found in Enterobacteriaceae. Here, we report a high incidence and endemic spread of NDM-1-producing CRE in Henan Province in China. Sixteen (33.3%) of the 48 CRE isolates obtained from patients during June 2011 to July 2012 were positive for blaNDM-1, and the gene was found to be carried on plasmids of various sizes (∼55 to ∼360 kb). These plasmids were readily ...


Identification Of A Novel G2073a Mutation In 23s Rrna In Amphenicol-Selected Mutants Of Campylobacter Jejuni, Licai Ma, Zhangqi Shen, Gaowa Naren, Hui Li, Xi Xia, Congming Wu, Jianzhong Shen, Qijing Zhang, Yang Wang Apr 2014

Identification Of A Novel G2073a Mutation In 23s Rrna In Amphenicol-Selected Mutants Of Campylobacter Jejuni, Licai Ma, Zhangqi Shen, Gaowa Naren, Hui Li, Xi Xia, Congming Wu, Jianzhong Shen, Qijing Zhang, Yang Wang

Veterinary Microbiology and Preventive Medicine Publications

Objectives

This study was conducted to examine the development and molecular mechanisms of amphenicol resistance in Campylobacter jejuni by using in vitro selection with chloramphenicol and florfenicol. The impact of the resistance development on growth rates was also determined using in vitro culture.

Methods

Chloramphenicol and florfenicol were used as selection agents to perform in vitro stepwise selection. Mutants resistant to the selective agents were obtained from the selection process. The mutant strains were compared with the parent strain for changes in MICs and growth rates. The 23S rRNA gene and the L4 and L22 ribosomal protein genes in the ...


Identification Of A Novel Membrane Transporter Mediating Resistance To Organic Arsenic In Campylobacter Jejuni, Zhangqi Shen, Taradon Luangtongkum, Zhiyi Qiang, Byeonghwa Jeon, Liping Wang, Qijing Zhang Apr 2014

Identification Of A Novel Membrane Transporter Mediating Resistance To Organic Arsenic In Campylobacter Jejuni, Zhangqi Shen, Taradon Luangtongkum, Zhiyi Qiang, Byeonghwa Jeon, Liping Wang, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

Although bacterial mechanisms involved in the resistance to inorganic arsenic are well understood, the molecular basis for organic arsenic resistance has not been described. Campylobacter jejuni, a major food-borne pathogen causing gastroenteritis in humans, is highly prevalent in poultry and is reportedly resistant to the arsenic compound roxarsone (4-hydroxy-3-nitrobenzenearsonic acid), which has been used as a feed additive in the poultry industry for growth promotion. In this study, we report the identification of a novel membrane transporter (named ArsP) that contributes to organic arsenic resistance in Campylobacter. ArsP is predicted to be a membrane permease containing eight transmembrane helices, distinct ...


Target Optimization For Peptide Nucleic Acid (Pna)-Mediated Antisense Inhibition Of The Cmeabc Multidrug Efflux Pump In Campylobacter Jejuni, Euna Oh, Qijing Zhang, Byeonghwa Jeon Feb 2014

Target Optimization For Peptide Nucleic Acid (Pna)-Mediated Antisense Inhibition Of The Cmeabc Multidrug Efflux Pump In Campylobacter Jejuni, Euna Oh, Qijing Zhang, Byeonghwa Jeon

Veterinary Microbiology and Preventive Medicine Publications

Objectives

CmeABC is a resistance-nodulation-cell division (RND)-type multidrug efflux pump conferring resistance to clinically important antibiotics in Campylobacter. This study aimed to identify the optimal target sites for the inhibition of CmeABC with antisense peptide nucleic acid (PNA).

Methods

Eighteen PNAs were designed to bind to the translational initiation regions of cmeABC, spanning the ribosome-binding site (RBS) and the start codon of the cmeABC genes. Campylobacter jejuni was treated with CmeABC-specific PNAs (CmeABC-PNAs) at various concentrations and subjected to western blotting to measure changes in the level of CmeABC expression. The MICs of ciprofloxacin and erythromycin were measured to ...


Multi-Omics Approaches To Deciphering A Hypervirulent Strain Of Campylobacter Jejuni, Zuowei Wu, Orhan Sahin, Zhangqi Shen, Peng Liu, William G. Miller, Qijing Zhang Nov 2013

Multi-Omics Approaches To Deciphering A Hypervirulent Strain Of Campylobacter Jejuni, Zuowei Wu, Orhan Sahin, Zhangqi Shen, Peng Liu, William G. Miller, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

Campylobacter jejuni clone SA recently emerged as the predominant cause of sheep abortion in the United States and is also associated with foodborne gastroenteritis in humans. A distinct phenotype of this clone is its ability to induce bacteremia and abortion. To facilitate understanding the pathogenesis of this hypervirulent clone, we analyzed a clinical isolate (IA3902) of clone SA using multi-omics approaches. The genome of IA3902 contains a circular chromosome of 1,635,045 bp and a circular plasmid of 37,174 bp. Comparative genomic analysis revealed that IA3902 is most closely related to C. jejuni NCTC11168, which is a reference ...


Synergistic Effects Of Anti-Cmea And Anti-Cmeb Peptide Nucleic Acids On Sensitizing Campylobacter Jejuni To Antibiotics, Yang Mu, Zhangqi Shen, Byeonghwa Jeon, Lei Dai, Qijing Zhang Sep 2013

Synergistic Effects Of Anti-Cmea And Anti-Cmeb Peptide Nucleic Acids On Sensitizing Campylobacter Jejuni To Antibiotics, Yang Mu, Zhangqi Shen, Byeonghwa Jeon, Lei Dai, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

The CmeABC efflux pump in Campylobacter jejuni confers resistance to structurally divergent antimicrobials, and inhibition of CmeABC represents a promising strategy to control antibiotic-resistant Campylobacter. Antisense peptide nucleic acids (PNAs) targeting the three components of CmeABC were evaluated for inhibition of CmeABC expression. The result revealed a synergistic effect of the PNAs targeting CmeA and CmeB on sensitizing C. jejuni to antibiotics. This finding further demonstrates the feasibility of using PNAs to potentiate antibiotics against antibiotic-resistant Campylobacter.


A Novel Two-Component Signaling System Facilitates Uropathogenic Escherichia Coli's Ability To Exploit Abundant Host Metabolites, Wentong Cai, Yvonne Wannemuehler, Giuseppe Dell'anna, Bryon A. Nicholson, Nicolle L. Barbieri, Subhashinie Kariyawasam, Yaping Feng, Catherine M. Logue, Lisa K. Nolan, Ganwu Li Jun 2013

A Novel Two-Component Signaling System Facilitates Uropathogenic Escherichia Coli's Ability To Exploit Abundant Host Metabolites, Wentong Cai, Yvonne Wannemuehler, Giuseppe Dell'anna, Bryon A. Nicholson, Nicolle L. Barbieri, Subhashinie Kariyawasam, Yaping Feng, Catherine M. Logue, Lisa K. Nolan, Ganwu Li

Veterinary Microbiology and Preventive Medicine Publications

wo-component signaling systems (TCSs) are major mechanisms by which bacteria adapt to environmental conditions. It follows then that TCSs would play important roles in the adaptation of pathogenic bacteria to host environments. However, no pathogen-associated TCS has been identified in uropathogenic Escherichia coli (UPEC). Here, we identified a novel TCS, which we termed KguS/KguR (KguS: α-ketoglutarate utilization sensor; KguR: α-ketoglutarate utilizationregulator) in UPEC CFT073, a strain isolated from human pyelonephritis. kguS/kguR was strongly associated with UPEC but was found only rarely among other E. coli including commensal and intestinal pathogenic strains. An in vivo competition assay in a ...


Complete Genome Sequence Of The Avian Pathogenic Escherichia Coli Strain Apec O78, Paul M. Mangiamele, Bryon A. Nicholson, Yvonne Wannemuehler, Torsten Seemann, Catherine M. Logue, Ganwu Li, Kelly A. Tivendale, Lisa K. Nolan Mar 2013

Complete Genome Sequence Of The Avian Pathogenic Escherichia Coli Strain Apec O78, Paul M. Mangiamele, Bryon A. Nicholson, Yvonne Wannemuehler, Torsten Seemann, Catherine M. Logue, Ganwu Li, Kelly A. Tivendale, Lisa K. Nolan

Veterinary Microbiology and Preventive Medicine Publications

Colibacillosis, caused by avian pathogenic Escherichia coli (APEC), is a significant disease, causing extensive animal and financial losses globally. Because of the significance of this disease, more knowledge is needed regarding APEC's mechanisms of virulence. Here, we present the fully closed genome sequence of a typical avian pathogenic E. coli strain belonging to the serogroup O78.


Comparison Of Multilocus Sequence Analysis And Virulence Genotyping Of Escherichia Coli From Live Birds, Retail Poultry Meat, And Human Extraintestinal Infection, Jessica L. Danzeisen, Yvonne Wannemuehler, Lisa K. Nolan, Timothy J. Johnson Mar 2013

Comparison Of Multilocus Sequence Analysis And Virulence Genotyping Of Escherichia Coli From Live Birds, Retail Poultry Meat, And Human Extraintestinal Infection, Jessica L. Danzeisen, Yvonne Wannemuehler, Lisa K. Nolan, Timothy J. Johnson

Veterinary Microbiology and Preventive Medicine Publications

To examine the correlations between virulence genotyping and multilocus sequence analysis of Escherichia coli from poultry and humans, 88 isolates were examined. The isolates were selected from a population of over 1000 based on their assignment to nine different virulence genotyping clusters. Clustering based on multilocus sequence analysis mostly correlated with virulence genotyping, although multilocus sequence analysis demonstrated higher discriminatory ability and greater reliability related to inferred phylogenetic relationships. No distinct patterns in host source were observed using inferred phylogeny through multilocus sequence analysis, indicating that human, avian, and retail meat isolates are diverse, and some belong to multiple shared ...


Mutational And Transcriptomic Changes Involved In The Development Of Macrolide Resistance In Campylobacter Jejuni, Haihong Hao, Zonghui Yuan, Zhangqi Shen, Jing Han, Orhan Sahin, Peng Liu, Qijing Zhang Mar 2013

Mutational And Transcriptomic Changes Involved In The Development Of Macrolide Resistance In Campylobacter Jejuni, Haihong Hao, Zonghui Yuan, Zhangqi Shen, Jing Han, Orhan Sahin, Peng Liu, Qijing Zhang

Veterinary Microbiology and Preventive Medicine Publications

Macrolide antibiotics are important for clinical treatment of infections caused by Campylobacter jejuni. Development of resistance to this class of antibiotics in Campylobacter is a complex process, and the dynamic molecular changes involved in this process remain poorly defined. Multiple lineages of macrolide-resistant mutants were selected by stepwise exposure of C. jejuni to escalating doses of erythromycin or tylosin. Mutations in target genes were determined by DNA sequencing, and the dynamic changes in the expression of antibiotic efflux transporters and the transcriptome of C. jejuni were examined by real-time reverse transcription-PCR, immunoblotting, and DNA microarray analysis. Multiple types of mutations ...


Genome Analysis And Phylogenetic Relatedness Of Gallibacterium Anatis Strains From Poultry, Timothy J. Johnson, Jessica L. Danzeisen, Darrell W. Trampel, Lisa K. Nolan, Torsten Seemann, Ragnhild J. Bager, Anders M. Bojesen Jan 2013

Genome Analysis And Phylogenetic Relatedness Of Gallibacterium Anatis Strains From Poultry, Timothy J. Johnson, Jessica L. Danzeisen, Darrell W. Trampel, Lisa K. Nolan, Torsten Seemann, Ragnhild J. Bager, Anders M. Bojesen

Veterinary Microbiology and Preventive Medicine Publications

Peritonitis is the major disease problem of laying hens in commercial table egg and parent stock operations. Despite its importance, the etiology and pathogenesis of this disease have not been completely clarified. Although avian pathogenic Escherichia coli (APEC) isolates have been incriminated as the causative agent of laying hen peritonitis, Gallibacterium anatis are frequently isolated from peritonitis lesions. Despite recent studies suggesting a role for G. anatis in the pathogenesis of peritonitis, little is known about the organism’s virulence mechanisms, genomic composition and population dynamics. Here, we compared the genome sequences of three G. anatis isolates in an effort ...


Fingerloop Activates Cargo Delivery And Unloading During Cotranslational Protein Targeting, Aileen R. Ariosa, Stacy S. Duncan, Oshu Saraogi, Xiaodong Lu, April Brown, Gregory J. Phillips, Shu-Ou Shan Jan 2013

Fingerloop Activates Cargo Delivery And Unloading During Cotranslational Protein Targeting, Aileen R. Ariosa, Stacy S. Duncan, Oshu Saraogi, Xiaodong Lu, April Brown, Gregory J. Phillips, Shu-Ou Shan

Veterinary Microbiology and Preventive Medicine Publications

During cotranslational protein targeting by the signal recognition particle (SRP), information about signal sequence binding in the SRP's M domain must be effectively communicated to its GTPase domain to turn on its interaction with the SRP receptor (SR) and thus deliver the cargo proteins to the membrane. A universally conserved “fingerloop” lines the signal sequence–binding groove of SRP; the precise role of this fingerloop in protein targeting has remained elusive. In this study, we show that the fingerloop plays important roles in SRP function by helping to induce the SRP into a more active conformation that facilitates multiple ...


Transferable Multiresistance Plasmids Carrying Cfr In Enterococcus Spp. From Swine And Farm Environment, Yang Liu, Yang Wang, Stefan Schwarz, Yun Li, Zhangqi Shen, Qijing Zhang, Congming Wu, Jianzhong Shen Jan 2013

Transferable Multiresistance Plasmids Carrying Cfr In Enterococcus Spp. From Swine And Farm Environment, Yang Liu, Yang Wang, Stefan Schwarz, Yun Li, Zhangqi Shen, Qijing Zhang, Congming Wu, Jianzhong Shen

Veterinary Microbiology and Preventive Medicine Publications

Seventy-seven porcine Enterococcus isolates with florfenicol MICs of ≥16 μg of were/ml screened for the presence of the multiresistance gene cfr, its location on plasmids, and its genetic environment. Three isolates—Enterococcus thailandicus 3-38 (from a porcine rectal swab collected at a pig farm), Enterococcus thailandicus W3, and Enterococcus faecalis W9-2 (the latter two from sewage at a different farm), carried the cfr gene. The SmaI pulsed-field gel electrophoresis patterns of the three isolates differed distinctly. In addition, E. faecalis W9-2 was assigned to a new multilocus sequence type ST469. Mating experiments and Southern blot analysis indicated that cfr ...


Escherichia Coli Isolates That Carry Vat, Fyua, Chua, And Yfcv Efficiently Colonize The Urinary Tract, Rachel R. Spurbeck, Paul C. Dinh Jr., Seth T. Walk, Ann E. Stapleton, Thomas M. Hooton, Lisa K. Nolan, Kwang Sik Kim, James R. Johnson, Harry L. T. Mobley Dec 2012

Escherichia Coli Isolates That Carry Vat, Fyua, Chua, And Yfcv Efficiently Colonize The Urinary Tract, Rachel R. Spurbeck, Paul C. Dinh Jr., Seth T. Walk, Ann E. Stapleton, Thomas M. Hooton, Lisa K. Nolan, Kwang Sik Kim, James R. Johnson, Harry L. T. Mobley

Veterinary Microbiology and Preventive Medicine Publications

Extraintestinal Escherichia coli (ExPEC), a heterogeneous group of pathogens, encompasses avian, neonatal meningitis, and uropathogenic E. coli strains. While several virulence factors are associated with ExPEC, there is no core set of virulence factors that can be used to definitively differentiate these pathotypes. Here we describe a multiplex of four virulence factor-encoding genes, yfcV, vat,fyuA, and chuA, highly associated with uropathogenic E. coli strains that can distinguish three groups of E. coli: diarrheagenic and animal-associated E. colistrains, human commensal and avian pathogenic E. coli strains, and uropathogenic and neonatal meningitis E. coli strains. Furthermore, human intestinal isolates that encode ...


Transcriptional Regulation Of The Cmeabc Multidrug Efflux Pump And The Kata Catalase By Cosr In Campylobacter Jejuni, Sunyoung Hwang, Qijing Zhang, Sangryeol Ryu, Byeonghwa Jeon Dec 2012

Transcriptional Regulation Of The Cmeabc Multidrug Efflux Pump And The Kata Catalase By Cosr In Campylobacter Jejuni, Sunyoung Hwang, Qijing Zhang, Sangryeol Ryu, Byeonghwa Jeon

Veterinary Microbiology and Preventive Medicine Publications

CosR is an essential response regulator in Campylobacter jejuni, a major food-borne pathogen causing enteritis worldwide. A transcriptomic analysis performed in this study discovered 93 genes whose transcriptional levels were changed >2-fold due to the repression of CosR expression by antisense peptide nucleic acid. The identified CosR-regulated genes are involved in various cellular functions, such as energy production, protein synthesis and folding, flagellum biogenesis, and lipid metabolism. Interestingly, 17 of the 93 CosR-regulated genes (18.3%) are predicted essential genes, indicating that CosR may participate in the regulation of vital biological processes in C. jejuni. In particular, CosR knockdown increased ...


Structural And Functional Analysis Of The Transcriptional Regulator Rv3066 Of Mycobacterium Tuberculosis, Jani Reddy Bolla, Sylvia V. Do, Feng Long, Lei Dai, Chih-Chia Su, Hsiang-Ting Lei, Xiao Chen, Jillian E. Gerkey, Daniel C. Murphy, Kanagalaghatta R. Rajashankar, Qijing Zhang, Edward W. Yu Oct 2012

Structural And Functional Analysis Of The Transcriptional Regulator Rv3066 Of Mycobacterium Tuberculosis, Jani Reddy Bolla, Sylvia V. Do, Feng Long, Lei Dai, Chih-Chia Su, Hsiang-Ting Lei, Xiao Chen, Jillian E. Gerkey, Daniel C. Murphy, Kanagalaghatta R. Rajashankar, Qijing Zhang, Edward W. Yu

Veterinary Microbiology and Preventive Medicine Publications

The Mmr multidrug efflux pump recognizes and actively extrudes a broad range of antimicrobial agents, and promotes the intrinsic resistance to these antimicrobials in Mycobacterium tuberculosis . The expression of Mmr is controlled by the TetR-like transcriptional regulator Rv3066, whose open reading frame is located downstream of the mmr operon. To understand the structural basis of Rv3066 regulation, we have determined the crystal structures of Rv3066, both in the absence and presence of bound ethidium, revealing an asymmetric homodimeric two-domain molecule with an entirely helical architecture. The structures underscore the flexibility and plasticity of the regulator essential for multidrug recognition. Comparison ...


Identification Of A Novel Genomic Island Conferring Resistance To Multiple Aminoglycoside Antibiotics In Campylobacter Coli, Shangshang Qin, Yang Wang, Qijing Zhang, Xia Chen, Zhangqi Shen, Fengru Deng, Congming Wu, Jianzhong Shen Oct 2012

Identification Of A Novel Genomic Island Conferring Resistance To Multiple Aminoglycoside Antibiotics In Campylobacter Coli, Shangshang Qin, Yang Wang, Qijing Zhang, Xia Chen, Zhangqi Shen, Fengru Deng, Congming Wu, Jianzhong Shen

Veterinary Microbiology and Preventive Medicine Publications

Historically, the incidence of gentamicin resistance in Campylobacter has been very low, but recent studies reported a high prevalence of gentamicin-resistant Campylobacter isolated from food-producing animals in China. The reason for the high prevalence was unknown and was addressed in this study. PCR screening identified aminoglycoside resistance genes aphA-3 and aphA-7 and the aadE–sat4–aphA-3 cluster among 41 Campylobacter isolates from broiler chickens. Importantly, a novel genomic island carrying multiple aminoglycoside resistance genes was identified in 26 aminoglycoside resistant Campylobacter coli strains. Sequence analysis revealed that the genomic island was inserted between cadF and COO1582 on the C. coli ...


Genotypic And Phenotypic Traits That Distinguish Neonatal Meningitis-Associated Escherichia Coli From Fecal E. Coli Isolates Of Healthy Human Hosts, Catherine M. Logue, Curt Doetkott, Paul M. Mangiamele, Yvonne Wannemuehler, Timothy J. Johnson, Kelly A. Tivendale, Ganwu Li, Julie S. Sherwood, Lisa K. Nolan Aug 2012

Genotypic And Phenotypic Traits That Distinguish Neonatal Meningitis-Associated Escherichia Coli From Fecal E. Coli Isolates Of Healthy Human Hosts, Catherine M. Logue, Curt Doetkott, Paul M. Mangiamele, Yvonne Wannemuehler, Timothy J. Johnson, Kelly A. Tivendale, Ganwu Li, Julie S. Sherwood, Lisa K. Nolan

Veterinary Microbiology and Preventive Medicine Publications

Neonatal meningitis Escherichia coli (NMEC) is one of the top causes of neonatal meningitis worldwide. Here, 85 NMEC and 204 fecal E. coli isolates from healthy humans (HFEC) were compared for possession of traits related to virulence, antimicrobial resistance, and plasmid content. This comparison was done to identify traits that typify NMEC and distinguish it from commensal strains to refine the definition of the NMEC subpathotype, identify traits that might contribute to NMEC pathogenesis, and facilitate choices of NMEC strains for future study. A large number of E. coli strains from both groups were untypeable, with the most common serogroups ...


Deep Sequencing-Based Transcriptome Analysis Of Chicken Spleen In Response To Avian Pathogenic Escherichia Coli (Apec) Infection, Qinghua Nie, Xiquan Zhang, Erin E. Sandford, Susan J. Lamont, Lisa K. Nolan Jul 2012

Deep Sequencing-Based Transcriptome Analysis Of Chicken Spleen In Response To Avian Pathogenic Escherichia Coli (Apec) Infection, Qinghua Nie, Xiquan Zhang, Erin E. Sandford, Susan J. Lamont, Lisa K. Nolan

Veterinary Microbiology and Preventive Medicine Publications

Avian pathogenic Escherichia coli (APEC) leads to economic losses in poultry production and is also a threat to human health. The goal of this study was to characterize the chicken spleen transcriptome and to identify candidate genes for response and resistance to APEC infection using Solexa sequencing. We obtained 14422935, 14104324, and 14954692 Solexa read pairs for non-challenged (NC), challenged-mild pathology (MD), and challenged-severe pathology (SV), respectively. A total of 148197 contigs and 98461 unigenes were assembled, of which 134949 contigs and 91890 unigenes match the chicken genome. In total, 12272 annotated unigenes take part in biological processes (11664), cellular ...


Prevalence Of Avian-Pathogenic Escherichia Coli Strain O1 Genomic Islands Among Extraintestinal And Commensal E. Coli Isolates, Timothy J. Johnson, Yvonne Wannemuehler, Subhashinie Kariyawasam, James R. Johnson, Catherine M. Logue, Lisa K. Nolan Jun 2012

Prevalence Of Avian-Pathogenic Escherichia Coli Strain O1 Genomic Islands Among Extraintestinal And Commensal E. Coli Isolates, Timothy J. Johnson, Yvonne Wannemuehler, Subhashinie Kariyawasam, James R. Johnson, Catherine M. Logue, Lisa K. Nolan

Veterinary Microbiology and Preventive Medicine Publications

Escherichia coli strains that cause disease outside the intestine are known as extraintestinal pathogenic E. coli (ExPEC) and include pathogens of humans and animals. Previously, the genome of avian-pathogenic E. coli (APEC) O1:K1:H7 strain O1, from ST95, was sequenced and compared to those of several other E. coli strains, identifying 43 genomic islands. Here, the genomic islands of APEC O1 were compared to those of other sequenced E. coli strains, and the distribution of 81 genes belonging to 12 APEC O1 genomic islands among 828 human and avian ExPEC and commensal E. coli isolates was determined. Multiple islands ...