Behavior and Target Site Selection of Conjugative Transposon Tn916in Two Different Strains of Toxigenic Clostridium difficile

ABSTRACTThe insertion sites of the conjugative transposon Tn916in the anaerobic pathogenClostridium difficilewere determined using Illumina Solexa high-throughput DNA sequencing of Tn916insertion libraries in two different clinical isolates: 630ΔE, an erythromycin-sensitive derivative of 630 (ribotype 012), and the ribotype 027 isolate R20291, which was responsible for a severe outbreak ofC. difficiledisease. A consensus 15-bp Tn916insertion sequence was identified which was similar in both strains, although an extended consensus sequence was observed in R20291. A search of theC. difficile630 genome showed that the Tn916insertion motif was present 100,987 times, with approximately 63,000 of these motifs located in genes and 35,000 in intergenic regions. To test the usefulness of Tn916as a mutagen, a functional screen allowed the isolation of a mutant. This mutant contained Tn916inserted into a gene involved in flagellar biosynthesis.

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The integration preference of Sleeping Beauty at non-TA site is related to the transposon end sequences

10.21203/rs.2.19101/v1 ◽

2019 ◽

Author(s):

Yiting Zhou ◽

Guangwei Ma ◽

Jiawen Yang ◽

Yabin Guo

Keyword(s):

Site Selection ◽

Genomic Dna ◽

Consensus Sequence ◽

Mouse Cell ◽

Sleeping Beauty ◽

Consensus Sequences ◽

Target Site Selection ◽

Target Sites ◽

End Sequences ◽

Selection Of

Abstract Background: Sleeping Beauty (SB) transposon had been thought to strictly integrate into TA dinucleotides. Recently, we found that SB also integrates into non-TA sites at a lower frequency. Here we performed further study on the non-TA integration of SB. Results: 1) SB can integrate into non-TA sites in HEK293T cells as well as in mouse cell lines. 2) Both the hyperactive transposase SB100X and the traditional SB11 catalyze integrations at non-TA sites. 3) The consensus sequence of the non-TA target sites only occur at the opposite side of the sequenced junction between transposon end and the genomic sequences, indicating that the integrations at non-TA sites are mainly aberrant integrations. 4) The consensus sequence of the non-TA target sites is corresponding to the transposon end sequence. When the transposon end sequence is mutated, the consensus sequences changed too. Conclusion: The interaction between the SB transposon end and genomic DNA may be involved in the target site selection of the SB integrations at non-TA sites.

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Genomic Epidemiology of a Protracted Hospital Outbreak Caused by a Toxin A-Negative Clostridium difficile Sublineage PCR Ribotype 017 Strain in London, England

Journal of Clinical Microbiology ◽

10.1128/jcm.00648-15 ◽

2015 ◽

Vol 53 (10) ◽

pp. 3141-3147 ◽

Cited By ~ 28

Author(s):

M. D. Cairns ◽

M. D. Preston ◽

T. D. Lawley ◽

T. G. Clark ◽

R. A. Stabler ◽

...

Keyword(s):

Clostridium Difficile ◽

De Novo ◽

University Hospital ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Conjugative Transposon ◽

Content Type ◽

Genomic Epidemiology ◽

Hospital Outbreak ◽

Nosocomial Diarrhea

Clostridium difficileremains the leading cause of nosocomial diarrhea worldwide, which is largely considered to be due to the production of two potent toxins: TcdA and TcdB. However, PCR ribotype (RT) 017, one of five clonal lineages of human virulentC. difficile, lacks TcdA expression but causes widespread disease. Whole-genome sequencing was applied to 35 isolates from hospitalized patients withC. difficileinfection (CDI) and two environmental ward isolates in London, England. The phylogenetic analysis of single nucleotide polymorphisms (SNPs) revealed a clonal cluster of temporally variable isolates from a single hospital ward at University Hospital Lewisham (UHL) that were distinct from other London hospital isolates.De novoassembled genomes revealed a 49-kbp putative conjugative transposon exclusive to this hospital clonal cluster which would not be revealed by current typing methodologies. This study identified three sublineages ofC. difficileRT017 that are circulating in London. Similar to the notorious RT027 lineage, which has caused global outbreaks of CDI since 2001, the lineage of toxin-defective RT017 strains appears to be continually evolving. By utilization of WGS technologies to identify SNPs and the evolution of clonal strains, the transmission of outbreaks caused by near-identical isolates can be retraced and identified.

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The Integration Preference of Sleeping Beauty at Non-TA Site Is Related to the Transposon End Sequences

Frontiers in Genetics ◽

10.3389/fgene.2021.639125 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yiting Zhou ◽

Guangwei Ma ◽

Jiawen Yang ◽

Zenghong Gao ◽

Yabin Guo

Keyword(s):

Site Selection ◽

Genomic Dna ◽

Consensus Sequence ◽

Mouse Cell ◽

Sleeping Beauty ◽

Consensus Sequences ◽

Target Site Selection ◽

Target Sites ◽

End Sequences ◽

Selection Of

Recently, we proved that Sleeping Beauty (SB) transposon integrates into non-TA sites at a lower frequency. Here, we performed a further study on the non-TA integration of SB and showed that (1) SB can integrate into non-TA sites in HEK293T cells as well as in mouse cell lines; (2) Both the hyperactive transposase SB100X and the traditional SB11 catalyze integrations at non-TA sites; (3) The consensus sequence of the non-TA target sites only occurs at the opposite side of the sequenced junction between the transposon end and the genomic sequences, indicating that the integrations at non-TA sites are mainly aberrant integrations; and (4) The consensus sequence of the non-TA target sites is corresponding to the transposon end sequence. The consensus sequences changed following the changes of the transposon ends. This result indicated that the interaction between the SB transposon end and genomic DNA (gDNA) may be involved in the target site selection of the SB integrations at non-TA sites.

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Target Site Selection of Pseudomonas putida Transposon Tn4652

Journal of Bacteriology ◽

10.1128/jb.01863-06 ◽

2007 ◽

Vol 189 (10) ◽

pp. 3918-3921 ◽

Cited By ~ 7

Author(s):

Paula Ann Kivistik ◽

Maia Kivisaar ◽

Rita Hõrak

Keyword(s):

Pseudomonas Putida ◽

Site Selection ◽

Consensus Sequence ◽

Target Site ◽

Target Site Selection ◽

Insertion Sites ◽

Site Recognition ◽

Selection Of

ABSTRACT We analyzed the target preferences of a Tn3 family transposon Tn4652. Alignment of 93 different insertion sites revealed a consensus sequence which resembles that of Tn3, indicating that despite a low similarity between Tn4652 and Tn3 transposases, their target site recognition is conserved.

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In VivoSelection of Rifamycin-Resistant Clostridium difficile during Rifaximin Therapy

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00974-12 ◽

2012 ◽

Vol 56 (11) ◽

pp. 6019-6020 ◽

Cited By ~ 21

Author(s):

Robert J. Carman ◽

James H. Boone ◽

Harish Grover ◽

Kimberly N. Wickham ◽

Li Chen

Keyword(s):

Clostridium Difficile ◽

Nucleotide Substitutions ◽

Single Nucleotide ◽

Content Type ◽

Selection Of

ABSTRACTWe report the selection ofClostridium difficileresistant to the rifamycin class of antibiotics in a patient within 32 h of receiving rifaximin for the treatment of recurrentC. difficilediarrhea. Resistance was associated with single nucleotide substitutions withinrpoB.

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PROMETHEE-based ranking of project managers based on the five personality traits

Kybernetes ◽

10.1108/k-10-2018-0551 ◽

2019 ◽

Vol 49 (4) ◽

pp. 1083-1102

Author(s):

Georgios N. Aretoulis ◽

Jason Papathanasiou ◽

Fani Antoniou

Keyword(s):

Personality Traits ◽

Questionnaire Survey ◽

Multicriteria Decision Making ◽

Project Managers ◽

Preference Ranking ◽

Infrastructure Projects ◽

Public Infrastructure ◽

Content Type ◽

The One ◽

Selection Of

Purpose This paper aims to rank and identify the most efficient project managers (PMs) based on personality traits, using Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) methodology. Design/methodology/approach The proposed methodology relies on the five personality traits. These were used as the selection criteria. A questionnaire survey among 82 experienced engineers was used to estimate the required weights per personality trait. A second two-part questionnaire survey aimed at recording the PMs profile and assess the performance of personality traits per PM. PMs with the most years of experience are selected to be ranked through Visual PROMETHEE. Findings The findings suggest that a competent PM is the one that scores low on the “Neuroticism” trait and high especially on the “Conscientiousness” trait. Research limitations/implications The research applied a psychometric test specifically designed for Greek people. Furthermore, the proposed methodology is based on the personality characteristics to rank the PMs and does not consider the technical skills. Furthermore, the type of project is not considered in the process of ranking PMs. Practical implications The findings could contribute in the selection of the best PM that maximizes the project team’s performance. Social implications Improved project team communication and collaboration leading to improved project performance through better communication and collaboration. This is an additional benefit for the society, especially in the delivery of public infrastructure projects. A lot of public infrastructure projects deviate largely as far as cost and schedule is concerned and this is an additional burden for public and society. Proper project management through efficient PMs would save people’s money and time. Originality/value Identification of the best PMbased on a combination of multicriteria decision-making and psychometric tests, which focus on personality traits.

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Characterizations of Clinical Isolates of Clostridium difficile by Toxin Genotypes and by Susceptibility to 12 Antimicrobial Agents, Including Fidaxomicin (OPT-80) and Rifaximin: a Multicenter Study in Taiwan

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00191-12 ◽

2012 ◽

Vol 56 (7) ◽

pp. 3943-3949 ◽

Cited By ~ 34

Author(s):

Chun-Hsing Liao ◽

Wen-Chien Ko ◽

Jang-Jih Lu ◽

Po-Ren Hsueh

Keyword(s):

Clostridium Difficile ◽

Care Setting ◽

Antimicrobial Agents ◽

Teaching Hospitals ◽

Binary Toxin ◽

Content Type ◽

Vancomycin Mics ◽

Major Teaching ◽

Southern Taiwan

ABSTRACTA total of 403 nonduplicate isolates ofClostridium difficilewere collected at three major teaching hospitals representing northern, central, and southern Taiwan from January 2005 to December 2010. Of these 403 isolates, 170 (42.2%) were presumed to be nontoxigenic due to the absence of genes for toxins A or B or binary toxin. The remaining 233 (57.8%) isolates carried toxin A and B genes, and 39 (16.7%) of these also had binary toxin genes. The MIC90of all isolates for fidaxomicin and rifaximin was 0.5 μg/ml (range, ≤0.015 to 0.5 μg/ml) and >128 μg/ml (range, ≤0.015 to >128 μg/ml), respectively. All isolates were susceptible to metronidazole (MIC90of 0.5 μg/ml; range, ≤0.03 to 4 μg/ml). Two isolates had reduced susceptibility to vancomycin (MICs, 4 μg/ml). Only 13.6% of isolates were susceptible to clindamycin (MIC of ≤2 μg/ml). Nonsusceptibility to moxifloxacin (n= 81, 20.1%) was accompanied by single or multiple mutations ingyrAandgyrBgenes in all but eight moxifloxacin-nonsusceptible isolates. Two previously unreportedgyrBmutations might independently confer resistance (MIC, 16 μg/ml), Ser416 to Ala and Glu466 to Lys. Moxifloxacin-resistant isolates were cross-resistant to ciprofloxacin and levofloxacin, but some moxifloxacin-nonsusceptible isolates remained susceptible to gemifloxacin or nemonoxacin at 0.5 μg/ml. This study found the diversity of toxigenic and nontoxigenic strains ofC. difficilein the health care setting in Taiwan. All isolates tested were susceptible to metronidazole and vancomycin. Fidaxomicin exhibited potentin vitroactivity against all isolates tested, while the more than 10% of Taiwanese isolates with rifaximin MICs of ≥128 μg/ml raises concerns.

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hfqPlays Important Roles in Virulence and Stress Adaptation in Cronobacter sakazakii ATCC 29544

Infection and Immunity ◽

10.1128/iai.03161-14 ◽

2015 ◽

Vol 83 (5) ◽

pp. 2089-2098 ◽

Cited By ~ 21

Author(s):

Seongok Kim ◽

Hyelyeon Hwang ◽

Kwang-Pyo Kim ◽

Hyunjin Yoon ◽

Dong-Hyun Kang ◽

...

Keyword(s):

Pathogenic Bacteria ◽

Bacterial Species ◽

Soft Agar ◽

Host Cells ◽

Neonatal Meningitis ◽

Animal Cells ◽

Content Type ◽

Flagellar Biosynthesis

Cronobacterspp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated withCronobacterinfection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq inC. sakazakiivirulence. In the absence ofhfq,C. sakazakiiwas highly attenuated in disseminationin vivo, showed defects in invasion (3-fold) into animal cells and survival (103-fold) within host cells, and exhibited low resistance to hydrogen peroxide (102-fold). Remarkably, the loss ofhfqled to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lackinghfq. Together, these data strongly suggest thathfqplays important roles in the virulence ofC. sakazakiiby participating in the regulation of multiple genes.

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Impact of Variations in Test Method Parameters onIn VitroActivity of Surotomycin against Clostridium difficile and Surotomycin Quality Control Limits for Broth Microdilution and Agar Dilution Susceptibility Testing

Journal of Clinical Microbiology ◽

10.1128/jcm.02881-15 ◽

2015 ◽

Vol 54 (3) ◽

pp. 749-753 ◽

Cited By ~ 1

Author(s):

Maria M. Traczewski ◽

Jennifer Deane ◽

Daniel Sahm ◽

Steven D. Brown ◽

Laurent Chesnel

Keyword(s):

Quality Control ◽

Clostridium Difficile ◽

Calcium Concentration ◽

Susceptibility Testing ◽

Test Method ◽

Test Parameter ◽

Content Type ◽

Parameter Variations ◽

Agar Dilution ◽

Control Limits

Test parameter variations were evaluated for their effects on surotomycin MICs. Calcium concentration was the only variable that influenced MICs; therefore, 50 μg/ml (standard for lipopeptide testing) is recommended. Quality control ranges forClostridium difficile(0.12 to 1 μg/ml) andEggerthella lenta(broth, 1 to 4 μg/ml; agar, 1 to 8 μg/ml) were approved by the Clinical and Laboratory Standards Institute based on these data.

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Does knowing overcome wanting? The impact of consumer knowledge and materialism upon credit card selection with young consumers

Young Consumers Insight and Ideas for Responsible Marketers ◽

10.1108/yc-01-2014-00418 ◽

2015 ◽

Vol 16 (1) ◽

pp. 50-70 ◽

Cited By ~ 7

Author(s):

Jakob Cakarnis ◽

Steve Peter D'Alessandro

Keyword(s):

Comparative Study ◽

Survey Research ◽

Credit Card ◽

Design Methodology ◽

Credit Cards ◽

Consumer Knowledge ◽

Content Type ◽

Young Professionals ◽

The Impact ◽

Selection Of

Purpose – This paper investigates the determinants of credit card use and misuse by student and young professionals. Critical to the research is the impact of materialism and knowledge on selection of the appropriate credit card. Design/methodology/approach – This study uses survey research and partial least squares to investigate credit card behaviors of students versus young professionals. Findings – In a comparative study of young professionals and students, it was found that consumer knowledge, as expected, leads to better consumer selection of credit cards. Materialism was also found to increase the motivation for more optimal consumer outcomes. For more experienced consumers, such as young professionals, it was found that despite them being more knowledgeable, they were more likely to select a credit card based on impulse. Originality/value – This paper examines how materialism may in fact encourage some consumers to make better decisions because they are more motivated to develop better knowledge. It also shows how better credit card selection may inhibit impulse purchasing.

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