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Pathogenicity Of An Emergent, Ovine Abortifacient Campylobacter Jejuni Clone Orally Inoculated Into Pregnant Guinea Pigs, Eric R. Burrough, Orhan Sahin, Paul J. Plummer, Qijing Zhang, Michael J. Yaeger 2017 Iowa State University

Pathogenicity Of An Emergent, Ovine Abortifacient Campylobacter Jejuni Clone Orally Inoculated Into Pregnant Guinea Pigs, Eric R. Burrough, Orhan Sahin, Paul J. Plummer, Qijing Zhang, Michael J. Yaeger

Paul Plummer

Objective—To compare pathogenicity of an emergent abortifacient Campylobacter jejuni (IA 3902) with that of reference strains after oral inoculation in pregnant guinea pigs. Animals—58 pregnant guinea pigs. Procedures—12 animals were challenged IP with C jejuni IA 3902 along with 5 sham-inoculated control animals to confirm abortifacient potential. Once pathogenicity was confirmed, challenge via oral inoculation was performed whereby 12 guinea pigs received IA 3902, 12 received C jejuni isolated from ovine feces (OF48), 12 received a fully sequenced human C jejuni isolate (NCTC 11168), and 5 were sham-inoculated control animals. After abortions, guinea pigs were euthanized; samples ...


Comparison Of Two Commercial Ovine Campylobacter Vaccines And An Experimental Bacterin In Guinea Pigs Inoculated With Campylobacter Jejuni, Eric R. Burrough, Orhan Sahin, Paul J. Plummer, Kevin D. DiVerde, Qijing Zhang, Michael J. Yaeger 2017 Iowa State University

Comparison Of Two Commercial Ovine Campylobacter Vaccines And An Experimental Bacterin In Guinea Pigs Inoculated With Campylobacter Jejuni, Eric R. Burrough, Orhan Sahin, Paul J. Plummer, Kevin D. Diverde, Qijing Zhang, Michael J. Yaeger

Paul Plummer

Objective—To compare efficacy of 2 commercial ovine Campylobacter vaccines and an experimental bacterin in guinea pigs following IP inoculation with Campylobacter jejuni IA3902. Animals—51 female guinea pigs. Procedures—Pregnant and nonpregnant animals were randomly assigned to 1 of 4 treatment groups and administered a commercial Campylobacter vaccine labeled for prevention of campylobacteriosis in sheep via two 5-mL doses 14 days apart (vaccine A; n = 13), another labeled for prevention of campylobacteriosis via two 2-mL doses (vaccine B; 12), an experimental bacterin prepared from the challenge strain (12), or a sham vaccine (14). Ten days later, animals were challenged ...


Distribution Of The Multidrug Resistance Gene Cfr In Staphylococcus Species Isolates From Swine Farms In China, Yang Wang, Wanjiang Zhang, Juan Wang, Congming Wu, Zhangqi Shen, Xiao Fu, Yang Yan, Qijing Zhang, Stefan Schwarz, Jianzhong Shen 2017 China Agricultural University

Distribution Of The Multidrug Resistance Gene Cfr In Staphylococcus Species Isolates From Swine Farms In China, Yang Wang, Wanjiang Zhang, Juan Wang, Congming Wu, Zhangqi Shen, Xiao Fu, Yang Yan, Qijing Zhang, Stefan Schwarz, Jianzhong Shen

Qijing Zhang

A total of 149 porcine Staphylococcus isolates with florfenicol MICs of ≥16 μg/ml were screened for the presence of the multiresistance gene cfr, its location on plasmids, and its genetic environment. In total, 125 isolates carried either cfr (16 isolates), fexA (92 isolates), or both genes (17 isolates). The 33 cfr-carrying staphylococci, which included isolates of the species Staphylococcus cohnii, S. arlettae, and S. saprophyticus in which the cfr gene has not been described before, exhibited a wide variety of SmaI pulsed-field gel electrophoresis patterns. In 18 cases, the cfr gene was located on plasmids. Four different types ...


Impaired Fitness And Transmission Of Macrolide-Resistant Campylobacter Jejuni In Its Natural Host, Taradon Luangtongkum, Zhangqi Shen, Virginia W. Seng, Orhan Sahin, Byeonghwa Jeon, Peng Liu, Qijing Zhang 2017 Iowa State University

Impaired Fitness And Transmission Of Macrolide-Resistant Campylobacter Jejuni In Its Natural Host, Taradon Luangtongkum, Zhangqi Shen, Virginia W. Seng, Orhan Sahin, Byeonghwa Jeon, Peng Liu, Qijing Zhang

Qijing Zhang

Campylobacter jejuni is a major zoonotic pathogen transmitted to humans via the food chain and is prevalent in chickens, a natural reservoir for this pathogenic organism. Due to the importance of macrolide antibiotics in clinical therapy of human campylobacteriosis, development of macrolide resistance in Campylobacter has become a concern for public health. To facilitate the control of macrolide-resistant Campylobacter, it is necessary to understand if macrolide resistance affects the fitness and transmission of Campylobacter in its natural host. In this study we conducted pairwise competitions and comingling experiments in chickens using clonally related and isogenic C. jejuni strains, which are ...


The New Genetic Environment Of Cfr On Plasmid Pbs-02 In A Bacillus Strain, Wan-Jiang Zhang, Cong-Ming Wu, Yang Wang, Zhang-Qi Shen, Lei Dai, Jing Han, Steven L. Foley, Jian-Zhong Shen, Qijing Zhang 2017 China Agricultural University

The New Genetic Environment Of Cfr On Plasmid Pbs-02 In A Bacillus Strain, Wan-Jiang Zhang, Cong-Ming Wu, Yang Wang, Zhang-Qi Shen, Lei Dai, Jing Han, Steven L. Foley, Jian-Zhong Shen, Qijing Zhang

Qijing Zhang

Sir,

The gene cfr, encoding a 23S rRNA methyltransferase, confers resistance to five chemically unrelated antimicrobial classes, including phenicols, lincosamides, oxazolidinones, pleuromutilins and streptogramin A (PhLOPSA), and has been observed mainly in staphylococcal isolates over the past decade.1–3 Our previous study reported a cfr-carrying plasmid, pBS-01, in a novel strain (BS-01) of a Bacillus species isolated from a pig farm in China.4 In our routine surveillance study on antimicrobial resistance in farm animals in 2010, another florfenicol and chloramphenicol-resistant Bacillus species strain (named BS-02) from swine faeces was identified. Gram staining, sequence analysis of the ...


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 2017 Seoul National University

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

Qijing Zhang

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 ...


Prevalence Of Tetracycline-Resistant Campylobacter In Organic Broilers During A Production Cycle, Taradon Luangtongkum, Teresa Y. Morishita, Lori Martin, Irene Choi, Orhan Sahin, Qijing Zhang 2017 The Ohio State University

Prevalence Of Tetracycline-Resistant Campylobacter In Organic Broilers During A Production Cycle, Taradon Luangtongkum, Teresa Y. Morishita, Lori Martin, Irene Choi, Orhan Sahin, Qijing Zhang

Qijing Zhang

Tetracycline (tet) resistance in Campylobacter isolated from organically raised broilers was investigated in this study. Two hundred forty-five samples from an organic broiler farm were collected weekly from the first week to the end of the production cycle, and they were cultured for thermophilic Campylobacter. Tetracycline resistance of these Campylobacter isolates was identified by the agar dilution method, whereas DNA fingerprinting profiles of tet-susceptible and tet-resistant strains were determined by pulsed-field gel electrophoresis (PFGE). None of the Campylobacter isolates from the third and the fourth week of the production period were resistant to tetracycline, whereas 66.7% of the isolates ...


Roles Of Lipooligosaccharide And Capsular Polysaccharide In Antimicrobial Resistance And Natural Transformation Of Campylobacter Jejuni, Byeonghwa Jeon, Wayne Muraoka, Alexandra Scupham, Qijing Zhang 2017 Iowa State University

Roles Of Lipooligosaccharide And Capsular Polysaccharide In Antimicrobial Resistance And Natural Transformation Of Campylobacter Jejuni, Byeonghwa Jeon, Wayne Muraoka, Alexandra Scupham, Qijing Zhang

Qijing Zhang

Objectives

This study is aimed to determine the role of capsular polysaccharide (CPS) and lipooligosaccharide (LOS) in modulating antimicrobial resistance and natural transformation of Campylobacter jejuni, an important food-borne human pathogen.

Methods

A series of C. jejuni mutants, which are defective in either CPS or LOS or both, were constructed. The antimicrobial susceptibility, bacterial surface hydrophobicity, natural transformation frequency and DNA binding and uptake were measured and compared between the mutants and the wild-type strain.

Results

Truncation of LOS greatly reduced (8-fold) the intrinsic resistance of C. jejuni to erythromycin, a key antibiotic used for treating human campylobacteriosis, while the ...


Emergence Of A Potent Multidrug Efflux Pump Variant That Enhances Campylobacter Resistance To Multiple Antibiotics, Hong Yao, Zhangqi Shen, Yang Wang, Fengru Deng, Dejun Liu, Gaowa Naren, Lei Dai, Chih-Chia Su, Bing Wang, Shaolin Wang, Congming Wu, Edward W. Yu, Qijing Zhang, Jianzhong Shen 2017 China Agricultural University

Emergence Of A Potent Multidrug Efflux Pump Variant That Enhances Campylobacter Resistance To Multiple Antibiotics, Hong Yao, Zhangqi Shen, Yang Wang, Fengru Deng, Dejun Liu, Gaowa Naren, Lei Dai, Chih-Chia Su, Bing Wang, Shaolin Wang, Congming Wu, Edward W. Yu, Qijing Zhang, Jianzhong Shen

Qijing Zhang

Bacterial antibiotic efflux pumps are key players in antibiotic resistance. Although their role in conferring multidrug resistance is well documented, the emergence of “super” efflux pump variants that enhance bacterial resistance to multiple drugs has not been reported. Here, we describe the emergence of a resistance-enhancing variant (named RE-CmeABC) of the predominant efflux pump CmeABC in Campylobacter, a major zoonotic pathogen whose resistance to antibiotics is considered a serious antibiotic resistance threat in the United States. Compared to the previously characterized CmeABC transporters, RE-CmeABC is much more potent in conferring Campylobacter resistance to antibiotics, which was shown by increased MICs ...


First Identification Of Ndm-4-Producing Escherichia Coli St410 In China, Shangshang Qin, Mengmeng Zhou, Qijing Zhang, Hengxun Tao, Yafei Ye, Huizhi Chen, Lijuan Xu, Hui Xu, Ping Wang, Xianju Feng 2017 Zhengzhou University

First Identification Of Ndm-4-Producing Escherichia Coli St410 In China, Shangshang Qin, Mengmeng Zhou, Qijing Zhang, Hengxun Tao, Yafei Ye, Huizhi Chen, Lijuan Xu, Hui Xu, Ping Wang, Xianju Feng

Qijing Zhang

Dear Editor, The worldwide dissemination of New Delhi metallo-β-lactamase 1 (NDM-1), an Ambler class B metallo-β-lactamase (MBL) conferring resistance to all β-lactams except monobactams, is of great concern for public health. NDM-4, which differs from NDM-1 by a single amino acid substitution (Met154Leu), was demonstrated to possess increased carbapenemase activity.


Fitness Of Antimicrobial-Resistant Campylobacter And Salmonella, Qijing Zhang, Orhan Sahin, Patrick F. McDermott, Sophie Payot 2017 Iowa State University

Fitness Of Antimicrobial-Resistant Campylobacter And Salmonella, Qijing Zhang, Orhan Sahin, Patrick F. Mcdermott, Sophie Payot

Qijing Zhang

Campylobacter and Salmonella are the most commonly reported bacterial causes of human foodborne infections, and increasing proportions of these pathogens become resistant to medically important antimicrobial agents, imposing a burden on public health. Acquisition of resistance to antibiotics affects the adaptation and evolution of Salmonella and Campylobacter in various environments. Many resistance-conferring mutations entail a biological fitness cost, while others (e.g. fluoroquinolone resistance in Campylobacter) have no cost or even enhanced fitness. In Salmonella, the fitness disadvantage due to antimicrobial resistance can be restored by acquired compensatory mutations, which occur both in vitro and in vivo. The compensated or ...


Genomic Insights Into Campylobacter Jejuni Virulence And Population Genetics, Zuowei Wu, Kathy Mou, Orhan Sahin, Qijing Zhang 2017 Iowa State University

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

Qijing Zhang

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, revealed ...


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 2017 China Agricultural University

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

Qijing Zhang

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 ...


Multi-Omics Approaches To Deciphering A Hypervirulent Strain Of Campylobacter Jejuni, Zuowei Wu, Orhan Sahin, Zhangqi Shen, Peng Liu, William G. Miller, Qijing Zhang 2017 Iowa State University

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

Qijing Zhang

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 ...


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 2017 Zhengzhou University

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

Qijing Zhang

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 transferrable to ...


Phenotypic And Genotypic Evidence For L-Fucose Utilization By Campylobacter Jejuni, Wayne T. Muroaka, Qijing Zhang 2017 U.S. Department of Agriculture

Phenotypic And Genotypic Evidence For L-Fucose Utilization By Campylobacter Jejuni, Wayne T. Muroaka, Qijing Zhang

Qijing Zhang

Campylobacter jejuni remains among the leading causes of bacterial food-borne illness. The current understanding of Campylobacter physiology suggests that it is asaccharolytic and is unable to catabolize exogenous carbohydrates. Contrary to this paradigm, we provide evidence for l-fucose utilization by C. jejuni. The fucose phenotype, shown in chemically defined medium, is strain specific and linked to an 11-open reading frame (ORF) plasticity region of the bacterial chromosome. By constructing a mutation in fucP (encoding a putative fucose permease), one of the genes in the plasticity region, we found that this locus is required for fucose utilization. Consistent with their function ...


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 2017 Zhengzhou University

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

Qijing Zhang

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.


Advances In Campylobacter Biology And Implications For Biotechnological Applications, Byeonghwa Jeon, Wayne T. Muraoka, Qijing Zhang 2017 Iowa State University

Advances In Campylobacter Biology And Implications For Biotechnological Applications, Byeonghwa Jeon, Wayne T. Muraoka, Qijing Zhang

Qijing Zhang

Campylobacter jejuni is a major foodborne pathogen of animal origin and a leading cause of bacterial gastroenteritis in humans. During the past decade, especially since the publication of the first C. jejuni genome sequence, major advances have been made in understanding the pathobiology and physiology of this organism. It is apparent that C. jejuni utilizes sophisticated mechanisms for effective colonization of the intestinal tracts in various animal species. Although Campylobacter is fragile in the environment and requires fastidious growth conditions, it exhibits great flexibility in the adaptation to various habitats including the gastrointestinal tract. This high adaptability is attributable to ...


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 2017 Iowa State University

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

Qijing Zhang

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.


Dual Repression Of The Multidrug Efflux Pump Cmeabc By Cosr And Cmer In Campylobacter Jejuni, Tara Grinnage-Pulley, Yang Mu, Lei Dai, Qijing Zhang 2017 Iowa State University

Dual Repression Of The Multidrug Efflux Pump Cmeabc By Cosr And Cmer In Campylobacter Jejuni, Tara Grinnage-Pulley, Yang Mu, Lei Dai, Qijing Zhang

Qijing Zhang

During transmission and intestinal colonization, Campylobacter jejuni, a major foodborne human pathogen, experiences oxidative stress. CosR, a response regulator in C. jejuni, modulates the oxidative stress response and represses expression of the CmeABC multidrug efflux pump. CmeABC, a key component in resistance to toxic compounds including antimicrobials and bile salts, is also under negative regulation by CmeR, a TetR family transcriptional regulator. How CosR and CmeR interact in binding to the cmeABC promoter and how CosR senses oxidative stress are still unknown. To answer these questions, we conducted various experiments utilizing electrophoretic mobility shift assays and transcriptional fusion assays ...


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