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Infection Of Commercial Laying Hens With Newcastle Disease Virus: Differing Responses Between Birds Provide Potential For Genetic Improvement Through Selection, Kaylee Rowland, Huaijun Zhou, Rodrigo Gallardo, David Bunn, Susan J. Lamont 2017 Iowa State University

Infection Of Commercial Laying Hens With Newcastle Disease Virus: Differing Responses Between Birds Provide Potential For Genetic Improvement Through Selection, Kaylee Rowland, Huaijun Zhou, Rodrigo Gallardo, David Bunn, Susan J. Lamont

Susan J. Lamont

Exotic Newcastle Disease Virus (ENDV) cause extremely rapid mortality in chickens after exposure to the virus. People rely heavily on poultry to provide protein and income in many places where NDV is not effectively controlled through vaccination and biosecurity. Losses from NDV contribute to worldwide hunger and poverty. It may be possible to use genetic selection to produce chickens that have a stronger immune response in the face of NDV challenge. For genetic selection to be successful, two major elements are required: differences in immune response among chickens and genetic control of these differences. This study clearly demonstrated the existence ...


Dietary Inclusion Of Colicin E1 Is Effective In Preventing Postweaning Diarrhea Caused By F18-Positive Escherichia Coli In Pigs, Sara A. Cutler, Steven M. Lonergan, Nancy A. Cornick, Anna K. Johnson, Chad H. Stahl 2017 Iowa State University

Dietary Inclusion Of Colicin E1 Is Effective In Preventing Postweaning Diarrhea Caused By F18-Positive Escherichia Coli In Pigs, Sara A. Cutler, Steven M. Lonergan, Nancy A. Cornick, Anna K. Johnson, Chad H. Stahl

Steven M. Lonergan

With worldwide concern over the use of antibiotics in animal agriculture and their contribution to the spread of antibiotic resistance, alternatives to conventional antibiotics are needed. Previous research in our laboratories has shown that colicin E1 is effective against some Escherichia coli strains responsible for postweaning diarrhea (PWD) in vitro. In this study we examined the efficacy of the dietary inclusion of colicin E1 in preventing experimentally induced PWD caused by F18-positive enterotoxigenic E. coli in young pigs. Twenty-four weaned pigs (23 days of age), identified by genotyping to be susceptible to F18-positive E. coliinfections, were individually housed and fed ...


Molecular Evidence For Zoonotic Transmission Of An Emergent, Highly Pathogenic Campylobacter Jejuni Clone In The United States, Orhan Sahin, Collette Fitzgerald, Steven Stroika, Shaohua Zhao, Rachel Sippy, Patrick Kwan, Paul J. Plummer, Jing Han, Michael Yaeger, Qijing Zhang 2017 Iowa State University

Molecular Evidence For Zoonotic Transmission Of An Emergent, Highly Pathogenic Campylobacter Jejuni Clone In The United States, Orhan Sahin, Collette Fitzgerald, Steven Stroika, Shaohua Zhao, Rachel Sippy, Patrick Kwan, Paul J. Plummer, Jing Han, Michael Yaeger, Qijing Zhang

Qijing Zhang

Campylobacter jejuni is a major zoonotic pathogen. A highly virulent, tetracycline-resistant C. jejuni clone (clone SA) has recently emerged in ruminant reservoirs and has become the predominant cause of sheep abortion in the United States. To determine whether clone SA is associated with human disease, we compared the clinical isolates of clone SA from sheep abortions with the human isolates of the PulseNet National Campylobacter databases at the CDC and the FDA using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and serotyping. The combined SmaI and KpnI PFGE pattern designations of clone SA from sheep were indistinguishable from those ...


Functional Characterization Of A Lipoprotein-Encoding Operon In Campylobacter Jejuni, Mayumi Oakland, Byeonghwa Jeon, Orhan Sahin, Zhangqi Shen, Qijing Zhang 2017 Iowa State University

Functional Characterization Of A Lipoprotein-Encoding Operon In Campylobacter Jejuni, Mayumi Oakland, Byeonghwa Jeon, Orhan Sahin, Zhangqi Shen, Qijing Zhang

Qijing Zhang

Background Bacterial lipoproteins have important functions in bacterial pathogenesis and physiology. In Campylobacter jejuni, a major foodborne pathogen causing gastroenteritis in humans, the majority of lipoproteins have not been functionally characterized. Previously, we showed by DNA microarray that CmeR, a transcriptional regulator repressing the expression of the multidrug efflux pump CmeABC, modulates the expression of a three-gene operon (cj0089, cj0090, and cj0091) encoding a cluster of lipoproteins in C. jejuni. Methodology/Principal Findings In this work, we characterized the function and regulation of the cj0089-cj0090-cj0091 operon. In contrast to the repression of cmeABC, CmeR activates the expression of the lipoprotein ...


Preliminary Structural Studies Of The Transcriptional Regulator Cmer From Campylobacter Jejuni, Chih-chia Su, Feng Shi, Ruoyu Gu, Ming Li, Gerry McDermott, Edward Yu, Qijing Zhang 2017 Iowa State University

Preliminary Structural Studies Of The Transcriptional Regulator Cmer From Campylobacter Jejuni, Chih-Chia Su, Feng Shi, Ruoyu Gu, Ming Li, Gerry Mcdermott, Edward Yu, Qijing Zhang

Qijing Zhang

In Campylobacter jejuni, a Gram-negative bacterial pathogen causing gastroenteritis in humans, the CmeR regulatory protein controls transcription of the multidrug transporter gene operon cmeABC. CmeR belongs to the TetR family of transcriptional regulators. The 210-residue CmeR consists of two functional motifs: an N-terminal DNA-binding domain and a C-terminal ligand-binding domain. It is predicted that the DNA-binding domain interacts directly with target promoters, while the C-terminal motif interacts with inducing ligands (such as bile salts). As an initial step towards confirming this structural model, recombinant CmeR protein containing a 6×His tag at the N-terminus was crystallized. Crystals of ligand-free CmeR ...


Identification Of A Key Amino Acid Of Luxs Involved In Ai-2 Production In Campylobacter Jejuni, Paul J. Plummer, Jinge Zhu, Masato Akiba, Dehua Pei, Qijing Zhang 2017 Iowa State University

Identification Of A Key Amino Acid Of Luxs Involved In Ai-2 Production In Campylobacter Jejuni, Paul J. Plummer, Jinge Zhu, Masato Akiba, Dehua Pei, Qijing Zhang

Qijing Zhang

Autoinducer-2 (AI-2) mediated quorum sensing has been associated with the expression of virulence factors in a number of pathogenic organisms and has been demonstrated to play a role in motility and cytolethal distending toxin (cdt) production in Campylobacter jejuni. We have initiated the work to determine the molecular basis of AI-2 synthesis and the biological functions of quorum sensing in C. jejuni. In this work, two naturally occurring variants of C. jejuni 81116 were identified, one producing high-levels of AI-2 while the other is defective in AI-2 synthesis. Sequence analysis revealed a G92D mutation in the luxS gene of the ...


Critical Role Of Luxs In The Virulence Of Campylobacter Jejuni In A Guinea Pig Model Of Abortion, Paul J. Plummer, Orhan Sahin, Eric Ryan Burrough, Rachel Sippy, Kathy T. Y. Mou, Jessica Rabenold, Michael Yaeger, Qijing Zhang 2017 Iowa State University

Critical Role Of Luxs In The Virulence Of Campylobacter Jejuni In A Guinea Pig Model Of Abortion, Paul J. Plummer, Orhan Sahin, Eric Ryan Burrough, Rachel Sippy, Kathy T. Y. Mou, Jessica Rabenold, Michael Yaeger, Qijing Zhang

Qijing Zhang

Previous studies on Campylobacter jejuni have demonstrated the role of LuxS in motility, cytolethal distending toxin production, agglutination, and intestinal colonization; however, its direct involvement in virulence has not been reported. In this study, we demonstrate a direct role of luxS in the virulence of C. jejuni in two different animal hosts. The IA3902 strain, a highly virulent sheep abortion strain recently described by our laboratory, along with its isogenic luxS mutant and luxScomplement strains, was inoculated by the oral route into both a pregnant guinea pig virulence model and a chicken colonization model. In both cases, the IA3902 ...


Key Role Of Mfd In The Development Of Fluoroquinolone Resistance In Campylobacter Jejuni, Jing Han, Orhan Sahin, Yi-Wen Barton, Qijing Zhang 2017 Iowa State University

Key Role Of Mfd In The Development Of Fluoroquinolone Resistance In Campylobacter Jejuni, Jing Han, Orhan Sahin, Yi-Wen Barton, Qijing Zhang

Qijing Zhang

Campylobacter jejuni is a major food-borne pathogen and a common causative agent of human enterocolitis. Fluoroquinolones are a key class of antibiotics prescribed for clinical treatment of enteric infections including campylobacteriosis, but fluoroquinolone-resistant Campylobacterreadily emerges under the antibiotic selection pressure. To understand the mechanisms involved in the development of fluoroquinolone-resistant Campylobacter, we compared the gene expression profiles of C. jejuni in the presence and absence of ciprofloxacin using DNA microarray. Our analysis revealed that multiple genes showed significant changes in expression in the presence of a suprainhibitory concentration of ciprofloxacin. Most importantly, ciprofloxacin induced the expression of mfd, which encodes ...


Molecular Mechanisms Of Mycoplasma Hyopneumoniae Adherence To Swine Respiratory Epithelial Cells, Qijing Zhang 2017 Iowa State University

Molecular Mechanisms Of Mycoplasma Hyopneumoniae Adherence To Swine Respiratory Epithelial Cells, Qijing Zhang

Qijing Zhang

A microtiter plate adherence assay for Mycoplasma hyopneumoniae was established by using purified swine tracheal cilia which are the natural targets for the mycoplasma. M. hyopneumoniae bound specifically to solubilized cilia immobilized onto microtiter plates. Dextran sulfate, heparin, chondroitin sulfate, laminin, mucin, and fucoidan significantly inhibited binding of the mycoplasmas to cilia. Heparin, mucin, fucoidan, and chondroitin sulfate interacted with the adhesins on the surface of mycoplasmas, whereas laminin blocked the receptors in cilia. Treatment of cilia with neuraminidase appeared to promote adherence of the mycoplasmas; whereas, treatment of cilia with sodium metaperiodate decreased the binding. In the second study ...


Identification Of New Delhi Metallo-Β-Lactamase 1 In Acinetobacter Lwoffii Of Food Animal Origin, Yang Wang, Conming Wu, Qijing Zhang, Jing Qi, Hebing Liu, Yu Wang, Tao He, Licai Ma, Jing Lai, Zhangqi Shen, Yuqing Liu, Jianzhong Shen 2017 China Agricultural University

Identification Of New Delhi Metallo-Β-Lactamase 1 In Acinetobacter Lwoffii Of Food Animal Origin, Yang Wang, Conming Wu, Qijing Zhang, Jing Qi, Hebing Liu, Yu Wang, Tao He, Licai Ma, Jing Lai, Zhangqi Shen, Yuqing Liu, Jianzhong Shen

Qijing Zhang

Background

To investigate the presence of metallo-β-lactamase (MBL) genes and the genetic environment of the New Delhi metallo-β-lactamase gene blaNDM-1 in bacteria of food animal origin.

Methodology/Principal Findings

Gram-negative bacteria with low susceptibility to imipenem (MIC>8 µg/mL) were isolated from swab samples collected from 15 animal farms and one slaughterhouse in eastern China. These bacteria were selected for phenotypic and molecular detection of known MBL genes and antimicrobial susceptibility testing. For the blaNDM-1 positive isolate, conjugation and transformation experiments were carried out to assess plasmid transfer. Southern blotting was conducted to localize the blaNDM-1 genes, and DNA ...


Genetic Basis And Functional Consequences Of Differential Expression Of The Cmeabc Efflux Pump In Campylobacter Jejuni Isolates, Tara Grinnage-Pulley, Qijing Zhang 2017 Iowa State University

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

Qijing Zhang

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 ...


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 2017 China Agricultural University

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

Qijing Zhang

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 ...


Genetic Diversity And Antimicrobial Susceptibility Of Campylobacter Jejuni Isolates Associated With Sheep Abortion In The United States And Great Britain, Zuowei Wu, Rachel Sippy, Orhan Sahin, Paul J. Plummer, Ana Vidal, Diane Newell, Qijing Zhang 2017 Iowa State University

Genetic Diversity And Antimicrobial Susceptibility Of Campylobacter Jejuni Isolates Associated With Sheep Abortion In The United States And Great Britain, Zuowei Wu, Rachel Sippy, Orhan Sahin, Paul J. Plummer, Ana Vidal, Diane Newell, Qijing Zhang

Qijing Zhang

Campylobacter infection is a leading cause of ovine abortion worldwide. Historically, genetically diverse Campylobacter fetus and Campylobacter jejunistrains have been implicated in such infections, but since 2003 a highly pathogenic, tetracycline-resistant C. jejuni clone (named SA) has become the predominant cause of sheep abortions in the United States. Whether clone SA was present in earlier U.S. abortion isolates (before 2000) and is associated with sheep abortions outside the United States are unknown. Here, we analyzed 54 C. jejuniisolates collected from U.S. sheep abortions at different time periods and compared them with 42 C. jejuni isolates associated with sheep ...


Adaptive Mechanisms Of Campylobacter Jejuni To Erythromycin Treatment, Qingqing Xia, Wayne T. Muraoka, Zhangqi Shen, Orhan Sahin, Hongning Wang, Zuowei Wu, Peng Liu, Qijing Zhang 2017 Iowa State University

Adaptive Mechanisms Of Campylobacter Jejuni To Erythromycin Treatment, Qingqing Xia, Wayne T. Muraoka, Zhangqi Shen, Orhan Sahin, Hongning Wang, Zuowei Wu, Peng Liu, Qijing Zhang

Qijing Zhang

Background Macrolide is the drug of choice to treat human campylobacteriosis, but Campylobacter resistance to this antibiotic is rising. The mechanisms employed by Campylobacter jejuni to adapt to erythromycin treatment remain unknown and are examined in this study. The transcriptomic response of C. jejuni NCTC 11168 to erythromycin (Ery) treatment was determined by competitive microarray hybridizations. Representative genes identified to be differentially expressed were further characterized by constructing mutants and assessing their involvement in antimicrobial susceptibility, oxidative stress tolerance, and chicken colonization. ResultsFollowing the treatment with an inhibitory dose of Ery, 139 genes were up-regulated and 119 were down-regulated. Many ...


Campylobacter In Poultry: Ecology And Potential Interventions, Orhan Sahin, Issmat I. Kassem, Zhangqi Shen, Jun Lin, Gireesh Rajashekara, Qijing Zhang 2017 Iowa State University

Campylobacter In Poultry: Ecology And Potential Interventions, Orhan Sahin, Issmat I. Kassem, Zhangqi Shen, Jun Lin, Gireesh Rajashekara, Qijing Zhang

Qijing Zhang

Avian hosts constitute a natural reservoir for thermophilic Campylobacterspecies, primarily Campylobacter jejuni and Campylobacter coli, and poultry flocks are frequently colonized in the intestinal tract with high numbers of the organisms. Prevalence rates in poultry, especially in slaughter-age broiler flocks, could reach as high as 100% on some farms. Despite the extensive colonization,Campylobacter is essentially a commensal in birds, although limited evidence has implicated the organism as a poultry pathogen. Although Campylobacter is insignificant for poultry health, it is a leading cause of food-borne gastroenteritis in humans worldwide, and contaminated poultry meat is recognized as the main source ...


Cmer Functions As A Pleiotropic Regulator And Is Required For Optimal Colonization Of Campylobacter Jejuni In Vivo, Baoqing Guo, Ying Wang, Feng Shi, Yi-Wen Barton, Paul J. Plummer, Donald L. Reynolds, Dan Nettleton, Tara Leigh Grinnage-Pulley, Jun Lin, Qijing Zhang 2017 Iowa State University

Cmer Functions As A Pleiotropic Regulator And Is Required For Optimal Colonization Of Campylobacter Jejuni In Vivo, Baoqing Guo, Ying Wang, Feng Shi, Yi-Wen Barton, Paul J. Plummer, Donald L. Reynolds, Dan Nettleton, Tara Leigh Grinnage-Pulley, Jun Lin, Qijing Zhang

Qijing Zhang

CmeR functions as a transcriptional repressor modulating the expression of the multidrug efflux pump CmeABC in Campylobacter jejuni. To determine if CmeR also regulates other genes in C. jejuni, we compared the transcriptome of thecmeR mutant with that of the wild-type strain using a DNA microarray. This comparison identified 28 genes that showed a ≥2-fold change in expression in thecmeR mutant. Independent real-time quantitative reverse transcription-PCR experiments confirmed 27 of the 28 differentially expressed genes. The CmeR-regulated genes encode membrane transporters, proteins involved in C4-dicarboxylate transport and utilization, enzymes for biosynthesis of capsular polysaccharide, and hypothetical proteins with unknown functions ...


Antibiotic Resistance Modulation And Modes Of Action Of (-)-Α-Pinene In Campylobacter Jejuni, Jasna Kovač, Katarina Šimunović, Zuowei Wu, Anja Klančnik, Franz Bucar, Qijing Zhang, Sonja Smole Možina 2017 University of Ljubljana

Antibiotic Resistance Modulation And Modes Of Action Of (-)-Α-Pinene In Campylobacter Jejuni, Jasna Kovač, Katarina Šimunović, Zuowei Wu, Anja Klančnik, Franz Bucar, Qijing Zhang, Sonja Smole Možina

Qijing Zhang

The aim of the study was to investigate the mode of action of (-)-α-pinene in terms of its modulation of antibiotic resistance in Campylobacter jejuni. Broth microdilution and ethidium bromide accumulation assays were used to evaluate the (-)-α-pinene antimicrobial activity, modulation of antimicrobial resistance, and inhibition of antimicrobial efflux. The target antimicrobial efflux systems were identified using an insertion mutagenesis approach, and C.jejuni adaptation to (-)-α-pinene was evaluated using DNA microarrays. Knock-out mutants of the key up-regulated transcriptional regulators hspR and hrcA were constructed to investigate their roles in C. jejuni adaptation to several stress factors, including osmolytes, and ...


Bacterial Community Profiling Of Milk Samples As A Means To Understand Culture-Negative Bovine Clinical Mastitis, Joanna S. Kuehn, Patrick J. Gorden, Daniel Munro, Ruichen Rong, Qunfeng Dong, Paul Joseph Plummer, Chong Wang, Gregory J. Phillips 2017 Iowa State University

Bacterial Community Profiling Of Milk Samples As A Means To Understand Culture-Negative Bovine Clinical Mastitis, Joanna S. Kuehn, Patrick J. Gorden, Daniel Munro, Ruichen Rong, Qunfeng Dong, Paul Joseph Plummer, Chong Wang, Gregory J. Phillips

Paul Plummer

Inflammation and infection of bovine mammary glands, commonly known as mastitis, imposes significant losses each year in the dairy industry worldwide. While several different bacterial species have been identified as causative agents of mastitis, many clinical mastitis cases remain culture negative, even after enrichment for bacterial growth. To understand the basis for this increasingly common phenomenon, the composition of bacterial communities from milk samples was analyzed using culture independent pyrosequencing of amplicons of 16S ribosomal RNA genes (16S rDNA). Comparisons were made of the microbial community composition of culture negative milk samples from mastitic quarters with that of non-mastitic quarters ...


Arca Controls Metabolism, Chemotaxis, And Motility Contributing To The Pathogenicity Of Avian Pathogenic Escherichia Coli, Fengwei Jiang, Chunxia An, Yinli Bao, Xuefeng Zhao, Robert L. Jernigan, Andrew Lithio, Dan Nettleton, Ling Li, Eve S. Wurtele, Lisa K. Nolan, Chengping Lu, Ganwu Li 2017 Nanjing Agricultural University

Arca Controls Metabolism, Chemotaxis, And Motility Contributing To The Pathogenicity Of Avian Pathogenic Escherichia Coli, Fengwei Jiang, Chunxia An, Yinli Bao, Xuefeng Zhao, Robert L. Jernigan, Andrew Lithio, Dan Nettleton, Ling Li, Eve S. Wurtele, Lisa K. Nolan, Chengping Lu, Ganwu Li

Lisa K. Nolan

Avian pathogenic Escherichia coli (APEC) strains cause one of the three most significant infectious diseases in the poultry industry and are also potential food-borne pathogens threating human health. In this study, we showed that ArcA (aerobic respiratory control), a global regulator important for E. coli's adaptation from anaerobic to aerobic conditions and control of that bacterium's enzymatic defenses against reactive oxygen species (ROS), is involved in the virulence of APEC. Deletion of arcA significantly attenuates the virulence of APEC in the duck model. Transcriptome sequencing (RNA-Seq) analyses comparing the APEC wild type and the arcA mutant indicate that ...


Use Of Alivecor Heart Monitor For Heart Rate And Rhythm Evaluation In Dairy Water Buffalo Calves (Bubalis Bubalis), Joe Smith, Jessica Ward, Tara Urbano, Mikaela Mueller 2017 Iowa State University

Use Of Alivecor Heart Monitor For Heart Rate And Rhythm Evaluation In Dairy Water Buffalo Calves (Bubalis Bubalis), Joe Smith, Jessica Ward, Tara Urbano, Mikaela Mueller

Jessica Ward

Smartphone-based ECG recording devices are a promising new diagnostic in veterinary medicine. However, these devices have not yet been demonstrated to work in water buffalo. A commercial, non-invasive, smartphone-based ECG (AliveCor Vet TM) monitoring device was field tested on water buffalo calves. Six neonatal water buffalo calves had an ECG simultaneously recorded with a standard medical ECG recorder and the AliveCor Vet device. A correlation of 0.75053 was observed between average heart rates obtained between AliveCor recordings when compared to those from the 6 lead ECG. 100% Rhythm agreement was met for all 12 recordings. The recordings of 4 ...


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