11 research outputs found

    Genexpressionsanalysen der frĂŒhen angeborenen Immunantwort des Haushuhns induziert durch eine Infektion mit Salmonella enteritidis mit Hilfe der Microarray Technologie

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    Salmonella infections in humans arise through chicken-based food such as eggs, egg-products, or chicken meat. The most common cause for these infections is Salmonella enteritidis, and the aim of this study has been to analyze the early innate immune response of chickens induced via this pathogen. Note that S. enteritidis is a host-adapted serovar, which only causes clinical findings in young chickens during their first week of life; adult chickens do not get sick, but may nevertheless act as inapparent infected carriers. We studied the reaction from the chicken immune system on S. enteritidis, using macrophage cultures as well as tissue samples of infected adult chickens. The gene expression studies were carried out by an “Agilent 4x44K chicken microarray” method. In our in vitro studies, we infected primary macrophages with S. enteritidis for 4 hours, using a MOI of 10. The gene expression studies resulted in the inductions of interleukins (IL1ÎČ, IL6, IL12p40, IL18), of chemokines (CCL1, CCL4 (K203), CCL20, CXCL8 (IL8), CXCL13), of some members of the tumor-nekrose-factor-superfamily (TNFSF), and of some toll-like receptors (TLR). Hence the cells have an inflammatory reaction. Particularly prominent were the expression changes of K60 (IL8 homolog), K203 (chCCLi2, MIP-1ÎČ), CCL20, and TL1a (TNFSF15). Finally, infected macrophages expressed a group of typical Th1-cytokines, including IL12p40, IL18, and IFN-Îł. In further analysis of our data, we focused on cytokines, chemokines, and members of the TNF-superfamily. In the ceca we found similar expression patterns within these three groups as was previously found for them in the macrophages study. In our in vivo studies, we infected chickens that were 8 weeks old and already had a well developed immune system. They were infected in the crop using a dose of 107 salmonella. At 5, 12, 24, and 48 hours of infection, we sampled the ceca and cecal tonsils for the bacterial, histological, and gene expression analyses. Already at 5 hours p.i., we were (for all but one animal) able to isolate bacteria from the ceca-tissue. The bacterial load reached its maximum at 12 hours p.i.. The infection of the cecal-tissues was confirmed in the histology, both by the detection of bacteria and by the occurrence of inflammatory cells. However, using histology, we could not detect any bacteria in cecal tonsils, which suggests that no infection was present in these organs. This suggestion was confirmed in gene expression analyses. When comparing the gene expression studies of cecal tonsils and ceca, the former showed lower counts of differential regulated genes (Tab. 11). Both their count maxima occurred at 12 hour p.i though. Moreover, at this time 41 significant regulated pathways had been identified.. In summary, the in vitro and the in vivo experiment both resulted in an initial inflammatory reaction, as well as in a typical Th1-cytokines reaction. To investigate functional characterisation of named candidate genes, in the first instance CCL20, CXCL8, K60, K203, and TL1a, future analyses of the innate immune response should involve them. This may contribute to a better understanding of the successful defense mechanisms against S. enteritidis in chicken, which may help to contain the amount of salmonellosis in humans

    A comprehensive analysis of Helicobacter pylori plasticity zones reveals that they are integrating conjugative elements with intermediate integration specificity

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    Background: The human gastric pathogen Helicobacter pylori is a paradigm for chronic bacterial infections. Its persistence in the stomach mucosa is facilitated by several mechanisms of immune evasion and immune modulation, but also by an unusual genetic variability which might account for the capability to adapt to changing environmental conditions during long-term colonization. This variability is reflected by the fact that almost each infected individual is colonized by a genetically unique strain. Strain-specific genes are dispersed throughout the genome, but clusters of genes organized as genomic islands may also collectively be present or absent. Results: We have comparatively analysed such clusters, which are commonly termed plasticity zones, in a high number of H. pylori strains of varying geographical origin. We show that these regions contain fixed gene sets, rather than being true regions of genome plasticity, but two different types and several subtypes with partly diverging gene content can be distinguished. Their genetic diversity is incongruent with variations in the rest of the genome, suggesting that they are subject to horizontal gene transfer within H. pylori populations. We identified 40 distinct integration sites in 45 genome sequences, with a conserved heptanucleotide motif that seems to be the minimal requirement for integration. Conclusions: The significant number of possible integration sites, together with the requirement for a short conserved integration motif and the high level of gene conservation, indicates that these elements are best described as integrating conjugative elements (ICEs) with an intermediate integration site specificity

    CagI Is an Essential Component of the Helicobacter pylori Cag Type IV Secretion System and Forms a Complex with CagL

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    Helicobacter pylori, the causative agent of type B gastritis, peptic ulcers, gastric adenocarcinoma and MALT lymphoma, uses the Cag type IV secretion system to induce a strong proinflammatory response in the gastric mucosa and to inject its effector protein CagA into gastric cells. CagA translocation results in altered host cell gene expression profiles and cytoskeletal rearrangements, and it is considered as a major bacterial virulence trait. Recently, it has been shown that binding of the type IV secretion apparatus to integrin receptors on target cells is a crucial step in the translocation process. Several bacterial proteins, including the Cag-specific components CagL and CagI, have been involved in this interaction. Here, we have examined the localization and interactions of CagI in the bacterial cell. Since the cagI gene overlaps and is co-transcribed with the cagL gene, the role of CagI for type IV secretion system function has been difficult to assess, and conflicting results have been reported regarding its involvement in the proinflammatory response. Using a marker-free gene deletion approach and genetic complementation, we show now that CagI is an essential component of the Cag type IV secretion apparatus for both CagA translocation and interleukin-8 induction. CagI is distributed over soluble and membrane-associated pools and seems to be partly surface-exposed. Deletion of several genes encoding essential Cag components has an impact on protein levels of CagI and CagL, suggesting that both proteins require partial assembly of the secretion apparatus. Finally, we show by co-immunoprecipitation that CagI and CagL interact with each other. Taken together, our results indicate that CagI and CagL form a functional complex which is formed at a late stage of secretion apparatus assembly

    Human Practice. Digital Ecologies. Our Future. : 14. Internationale Tagung Wirtschaftsinformatik (WI 2019) : Tagungsband

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    Erschienen bei: universi - UniversitĂ€tsverlag Siegen. - ISBN: 978-3-96182-063-4Aus dem Inhalt: Track 1: Produktion & Cyber-Physische Systeme Requirements and a Meta Model for Exchanging Additive Manufacturing Capacities Service Systems, Smart Service Systems and Cyber- Physical Systems—What’s the difference? Towards a Unified Terminology Developing an Industrial IoT Platform – Trade-off between Horizontal and Vertical Approaches Machine Learning und Complex Event Processing: Effiziente Echtzeitauswertung am Beispiel Smart Factory Sensor retrofit for a coffee machine as condition monitoring and predictive maintenance use case Stakeholder-Analyse zum Einsatz IIoT-basierter Frischeinformationen in der Lebensmittelindustrie Towards a Framework for Predictive Maintenance Strategies in Mechanical Engineering - A Method-Oriented Literature Analysis Development of a matching platform for the requirement-oriented selection of cyber physical systems for SMEs Track 2: Logistic Analytics An Empirical Study of Customers’ Behavioral Intention to Use Ridepooling Services – An Extension of the Technology Acceptance Model Modeling Delay Propagation and Transmission in Railway Networks What is the impact of company specific adjustments on the acceptance and diffusion of logistic standards? Robust Route Planning in Intermodal Urban Traffic Track 3: Unternehmensmodellierung & Informationssystemgestaltung (Enterprise Modelling & Information Systems Design) Work System Modeling Method with Different Levels of Specificity and Rigor for Different Stakeholder Purposes Resolving Inconsistencies in Declarative Process Models based on Culpability Measurement Strategic Analysis in the Realm of Enterprise Modeling – On the Example of Blockchain-Based Initiatives for the Electricity Sector Zwischenbetriebliche Integration in der Möbelbranche: Konfigurationen und Einflussfaktoren Novices’ Quality Perceptions and the Acceptance of Process Modeling Grammars Entwicklung einer Definition fĂŒr Social Business Objects (SBO) zur Modellierung von Unternehmensinformationen Designing a Reference Model for Digital Product Configurators Terminology for Evolving Design Artifacts Business Role-Object Specification: A Language for Behavior-aware Structural Modeling of Business Objects Generating Smart Glasses-based Information Systems with BPMN4SGA: A BPMN Extension for Smart Glasses Applications Using Blockchain in Peer-to-Peer Carsharing to Build Trust in the Sharing Economy Testing in Big Data: An Architecture Pattern for a Development Environment for Innovative, Integrated and Robust Applications Track 4: Lern- und Wissensmanagement (e-Learning and Knowledge Management) eGovernment Competences revisited – A Literature Review on necessary Competences in a Digitalized Public Sector Say Hello to Your New Automated Tutor – A Structured Literature Review on Pedagogical Conversational Agents Teaching the Digital Transformation of Business Processes: Design of a Simulation Game for Information Systems Education Conceptualizing Immersion for Individual Learning in Virtual Reality Designing a Flipped Classroom Course – a Process Model The Influence of Risk-Taking on Knowledge Exchange and Combination Gamified Feedback durch Avatare im Mobile Learning Alexa, Can You Help Me Solve That Problem? - Understanding the Value of Smart Personal Assistants as Tutors for Complex Problem Tasks Track 5: Data Science & Business Analytics Matching with Bundle Preferences: Tradeoff between Fairness and Truthfulness Applied image recognition: guidelines for using deep learning models in practice Yield Prognosis for the Agrarian Management of Vineyards using Deep Learning for Object Counting Reading Between the Lines of Qualitative Data – How to Detect Hidden Structure Based on Codes Online Auctions with Dual-Threshold Algorithms: An Experimental Study and Practical Evaluation Design Features of Non-Financial Reward Programs for Online Reviews: Evaluation based on Google Maps Data Topic Embeddings – A New Approach to Classify Very Short Documents Based on Predefined Topics Leveraging Unstructured Image Data for Product Quality Improvement Decision Support for Real Estate Investors: Improving Real Estate Valuation with 3D City Models and Points of Interest Knowledge Discovery from CVs: A Topic Modeling Procedure Online Product Descriptions – Boost for your Sales? EntscheidungsunterstĂŒtzung durch historienbasierte Dienstreihenfolgeplanung mit Pattern A Semi-Automated Approach for Generating Online Review Templates Machine Learning goes Measure Management: Leveraging Anomaly Detection and Parts Search to Improve Product-Cost Optimization Bedeutung von Predictive Analytics fĂŒr den theoretischen Erkenntnisgewinn in der IS-Forschung Track 6: Digitale Transformation und Dienstleistungen Heuristic Theorizing in Software Development: Deriving Design Principles for Smart Glasses-based Systems Mirroring E-service for Brick and Mortar Retail: An Assessment and Survey Taxonomy of Digital Platforms: A Platform Architecture Perspective Value of Star Players in the Digital Age Local Shopping Platforms – Harnessing Locational Advantages for the Digital Transformation of Local Retail Outlets: A Content Analysis A Socio-Technical Approach to Manage Analytics-as-a-Service – Results of an Action Design Research Project Characterizing Approaches to Digital Transformation: Development of a Taxonomy of Digital Units Expectations vs. Reality – Benefits of Smart Services in the Field of Tension between Industry and Science Innovation Networks and Digital Innovation: How Organizations Use Innovation Networks in a Digitized Environment Characterising Social Reading Platforms— A Taxonomy-Based Approach to Structure the Field Less Complex than Expected – What Really Drives IT Consulting Value Modularity Canvas – A Framework for Visualizing Potentials of Service Modularity Towards a Conceptualization of Capabilities for Innovating Business Models in the Industrial Internet of Things A Taxonomy of Barriers to Digital Transformation Ambidexterity in Service Innovation Research: A Systematic Literature Review Design and success factors of an online solution for cross-pillar pension information Track 7: IT-Management und -Strategie A Frugal Support Structure for New Software Implementations in SMEs How to Structure a Company-wide Adoption of Big Data Analytics The Changing Roles of Innovation Actors and Organizational Antecedents in the Digital Age Bewertung des Kundennutzens von Chatbots fĂŒr den Einsatz im Servicedesk Understanding the Benefits of Agile Software Development in Regulated Environments Are Employees Following the Rules? On the Effectiveness of IT Consumerization Policies Agile and Attached: The Impact of Agile Practices on Agile Team Members’ Affective Organisational Commitment The Complexity Trap – Limits of IT Flexibility for Supporting Organizational Agility in Decentralized Organizations Platform Openness: A Systematic Literature Review and Avenues for Future Research Competence, Fashion and the Case of Blockchain The Digital Platform Otto.de: A Case Study of Growth, Complexity, and Generativity Track 8: eHealth & alternde Gesellschaft Security and Privacy of Personal Health Records in Cloud Computing Environments – An Experimental Exploration of the Impact of Storage Solutions and Data Breaches Patientenintegration durch Pfadsysteme Digitalisierung in der StressprĂ€vention – eine qualitative Interviewstudie zu Nutzenpotenzialen User Dynamics in Mental Health Forums – A Sentiment Analysis Perspective Intent and the Use of Wearables in the Workplace – A Model Development Understanding Patient Pathways in the Context of Integrated Health Care Services - Implications from a Scoping Review Understanding the Habitual Use of Wearable Activity Trackers On the Fit in Fitness Apps: Studying the Interaction of Motivational Affordances and Users’ Goal Orientations in Affecting the Benefits Gained Gamification in Health Behavior Change Support Systems - A Synthesis of Unintended Side Effects Investigating the Influence of Information Incongruity on Trust-Relations within Trilateral Healthcare Settings Track 9: Krisen- und KontinuitĂ€tsmanagement Potentiale von IKT beim Ausfall kritischer Infrastrukturen: Erwartungen, Informationsgewinnung und Mediennutzung der Zivilbevölkerung in Deutschland Fake News Perception in Germany: A Representative Study of People’s Attitudes and Approaches to Counteract Disinformation Analyzing the Potential of Graphical Building Information for Fire Emergency Responses: Findings from a Controlled Experiment Track 10: Human-Computer Interaction Towards a Taxonomy of Platforms for Conversational Agent Design Measuring Service Encounter Satisfaction with Customer Service Chatbots using Sentiment Analysis Self-Tracking and Gamification: Analyzing the Interplay of Motivations, Usage and Motivation Fulfillment Erfolgsfaktoren von Augmented-Reality-Applikationen: Analyse von Nutzerrezensionen mit dem Review-Mining-Verfahren Designing Dynamic Decision Support for Electronic Requirements Negotiations Who is Stressed by Using ICTs? A Qualitative Comparison Analysis with the Big Five Personality Traits to Understand Technostress Walking the Middle Path: How Medium Trade-Off Exposure Leads to Higher Consumer Satisfaction in Recommender Agents Theory-Based Affordances of Utilitarian, Hedonic and Dual-Purposed Technologies: A Literature Review Eliciting Customer Preferences for Shopping Companion Apps: A Service Quality Approach The Role of Early User Participation in Discovering Software – A Case Study from the Context of Smart Glasses The Fluidity of the Self-Concept as a Framework to Explain the Motivation to Play Video Games Heart over Heels? An Empirical Analysis of the Relationship between Emotions and Review Helpfulness for Experience and Credence Goods Track 11: Information Security and Information Privacy Unfolding Concerns about Augmented Reality Technologies: A Qualitative Analysis of User Perceptions To (Psychologically) Own Data is to Protect Data: How Psychological Ownership Determines Protective Behavior in a Work and Private Context Understanding Data Protection Regulations from a Data Management Perspective: A Capability-Based Approach to EU-GDPR On the Difficulties of Incentivizing Online Privacy through Transparency: A Qualitative Survey of the German Health Insurance Market What is Your Selfie Worth? A Field Study on Individuals’ Valuation of Personal Data Justification of Mass Surveillance: A Quantitative Study An Exploratory Study of Risk Perception for Data Disclosure to a Network of Firms Track 12: Umweltinformatik und nachhaltiges Wirtschaften KommunikationsfĂ€den im Nadelöhr – Fachliche Prozessmodellierung der Nachhaltigkeitskommunikation am Kapitalmarkt Potentiale und Herausforderungen der Materialflusskostenrechnung Computing Incentives for User-Based Relocation in Carsharing Sustainability’s Coming Home: Preliminary Design Principles for the Sustainable Smart District Substitution of hazardous chemical substances using Deep Learning and t-SNE A Hierarchy of DSMLs in Support of Product Life-Cycle Assessment A Survey of Smart Energy Services for Private Households Door-to-Door Mobility Integrators as Keystone Organizations of Smart Ecosystems: Resources and Value Co-Creation – A Literature Review Ein EntscheidungsunterstĂŒtzungssystem zur ökonomischen Bewertung von Mieterstrom auf Basis der Clusteranalyse Discovering Blockchain for Sustainable Product-Service Systems to enhance the Circular Economy Digitale RĂŒckverfolgbarkeit von Lebensmitteln: Eine verbraucherinformatische Studie Umweltbewusstsein durch audiovisuelles Content Marketing? Eine experimentelle Untersuchung zur Konsumentenbewertung nachhaltiger Smartphones Towards Predictive Energy Management in Information Systems: A Research Proposal A Web Browser-Based Application for Processing and Analyzing Material Flow Models using the MFCA Methodology Track 13: Digital Work - Social, mobile, smart On Conversational Agents in Information Systems Research: Analyzing the Past to Guide Future Work The Potential of Augmented Reality for Improving Occupational First Aid Prevent a Vicious Circle! The Role of Organizational IT-Capability in Attracting IT-affine Applicants Good, Bad, or Both? Conceptualization and Measurement of Ambivalent User Attitudes Towards AI A Case Study on Cross-Hierarchical Communication in Digital Work Environments ‘Show Me Your People Skills’ - Employing CEO Branding for Corporate Reputation Management in Social Media A Multiorganisational Study of the Drivers and Barriers of Enterprise Collaboration Systems-Enabled Change The More the Merrier? The Effect of Size of Core Team Subgroups on Success of Open Source Projects The Impact of Anthropomorphic and Functional Chatbot Design Features in Enterprise Collaboration Systems on User Acceptance Digital Feedback for Digital Work? Affordances and Constraints of a Feedback App at InsurCorp The Effect of Marker-less Augmented Reality on Task and Learning Performance Antecedents for Cyberloafing – A Literature Review Internal Crowd Work as a Source of Empowerment - An Empirical Analysis of the Perception of Employees in a Crowdtesting Project Track 14: GeschĂ€ftsmodelle und digitales Unternehmertum Dividing the ICO Jungle: Extracting and Evaluating Design Archetypes Capturing Value from Data: Exploring Factors Influencing Revenue Model Design for Data-Driven Services Understanding the Role of Data for Innovating Business Models: A System Dynamics Perspective Business Model Innovation and Stakeholder: Exploring Mechanisms and Outcomes of Value Creation and Destruction Business Models for Internet of Things Platforms: Empirical Development of a Taxonomy and Archetypes Revitalizing established Industrial Companies: State of the Art and Success Principles of Digital Corporate Incubators When 1+1 is Greater than 2: Concurrence of Additional Digital and Established Business Models within Companies Special Track 1: Student Track Investigating Personalized Price Discrimination of Textile-, Electronics- and General Stores in German Online Retail From Facets to a Universal Definition – An Analysis of IoT Usage in Retail Is the Technostress Creators Inventory Still an Up-To-Date Measurement Instrument? Results of a Large-Scale Interview Study Application of Media Synchronicity Theory to Creative Tasks in Virtual Teams Using the Example of Design Thinking TrustyTweet: An Indicator-based Browser-Plugin to Assist Users in Dealing with Fake News on Twitter Application of Process Mining Techniques to Support Maintenance-Related Objectives How Voice Can Change Customer Satisfaction: A Comparative Analysis between E-Commerce and Voice Commerce Business Process Compliance and Blockchain: How Does the Ethereum Blockchain Address Challenges of Business Process Compliance? Improving Business Model Configuration through a Question-based Approach The Influence of Situational Factors and Gamification on Intrinsic Motivation and Learning Evaluation von ITSM-Tools fĂŒr Integration und Management von Cloud-Diensten am Beispiel von ServiceNow How Software Promotes the Integration of Sustainability in Business Process Management Criteria Catalog for Industrial IoT Platforms from the Perspective of the Machine Tool Industry Special Track 3: Demos & Prototyping Privacy-friendly User Location Tracking with Smart Devices: The BeaT Prototype Application-oriented robotics in nursing homes Augmented Reality for Set-up Processe Mixed Reality for supporting Remote-Meetings Gamification zur Motivationssteigerung von Werkern bei der Betriebsdatenerfassung Automatically Extracting and Analyzing Customer Needs from Twitter: A “Needmining” Prototype GaNEsHA: Opportunities for Sustainable Transportation in Smart Cities TUCANA: A platform for using local processing power of edge devices for building data-driven services Demonstrator zur Beschreibung und Visualisierung einer kritischen Infrastruktur Entwicklung einer alltagsnahen persuasiven App zur Bewegungsmotivation fĂŒr Ă€ltere Nutzerinnen und Nutzer A browser-based modeling tool for studying the learning of conceptual modeling based on a multi-modal data collection approach Exergames & Dementia: An interactive System for People with Dementia and their Care-Network Workshops Workshop Ethics and Morality in Business Informatics (Workshop Ethik und Moral in der Wirtschaftsinformatik – EMoWI’19) Model-Based Compliance in Information Systems - Foundations, Case Description and Data Set of the MobIS-Challenge for Students and Doctoral Candidates Report of the Workshop on Concepts and Methods of Identifying Digital Potentials in Information Management Control of Systemic Risks in Global Networks - A Grand Challenge to Information Systems Research Die Mitarbeiter von morgen - Kompetenzen kĂŒnftiger Mitarbeiter im Bereich Business Analytics Digitaler Konsum: Herausforderungen und Chancen der Verbraucherinformati

    Localization of CagI and CagL in bacterial cell fractions.

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    <p>(A) <i>H. pylori</i> cells grown in liquid culture for 24–48 hours were lysed by ultrasonication and subsequently fractionated into soluble and insoluble proteins by ultracentrifugation. Ultracentrifugation pellets containing membrane-associated and other insoluble proteins were extracted with 1% triton X-100 to separate outer membrane-associated (TX100 insol) from inner membrane-associated (TX100 sol) proteins. Comparable amounts of each fraction were analysed by immunoblot for their CagI and CagL content. As controls, immunoblots against the outer membrane-associated proteins CagX and AlpB, and the partly soluble and partly inner membrane-associated protein RecA were used. Representative immunoblots are shown. CagI and CagL bands are indicated by arrowheads. (B) Ultracentrifugation pellets were resuspended and subjected to isopycnic density gradient centrifugation on 25–60% sucrose gradients. Fractions were collected from the gradients and analyzed by immunoblotting with the indicated antisera. CagI and CagL bands are indicated by arrowheads. (C) Bacteria were subjected to limited proteolytic digestion by proteinase K. Equal amounts of untreated control cells (P12) and proteinase K-treated bacteria (P12 PK) were analyzed by immunoblot with the indicated antisera.</p

    Presence of several Cag components influences CagI and CagL protein levels.

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    <p>Whole cell lysates of equal amounts of the wild-type strain P12 and of isogenic mutants in single <i>cag</i> genes (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0035341#pone-0035341-t001" target="_blank">Table 1</a>) were separated by SDS-PAGE and examined by immunoblotting with the anti-CagI and anti-CagL antisera, respectively. Representative immunoblots are shown. Note that the <i>cagI</i> mutant shown here was generated with plasmid pWS327. Arrowheads indicate the positions of CagI and CagL protein bands, respectively.</p

    CagI is an essential component of the Cag type IV secretion apparatus.

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    <p>(A) AGS cells were infected for 4 h with the indicated strains at a multiplicity of infection of 100, and infection lysates were examined by immunoblot for the presence of CagA and CagA tyrosine phosphorylation (PTyr). Infected cells were also examined by light microscopy for induction of the hummingbird phenotype. (B) Culture supernatants of AGS cells infected with the indicated <i>H. pylori</i> strains as above were tested for their IL-8 content. IL-8 values induced by wild-type P12 were set to 100%, and other values are given in relation to wild-type levels. Data shown are average values of at least three independent experiments with standard deviations.</p

    Operon organization of the <i>cagH</i>, <i>cagI</i> and <i>cagL</i> genes.

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    <p>(A) Gene arrangement of the <i>cag</i> pathogenicity island in <i>H. pylori</i> strain P12. Genes are represented as arrows, and their designations are indicated below. The operon containing <i>cagI</i> may comprise five (<i>cagF</i>, <i>cagG</i>, <i>cagH</i>, <i>cagI</i> and <i>cagL</i>) or even more genes, but <i>cagH</i>, <i>cagI</i> and <i>cagL</i> are particularly tightly associated since they have overlapping reading frames or Shine-Dalgarno (SD) sequences. Translational starts are indicated by arrows. (B) A <i>cagI</i> deletion mutant containing a terminatorless chloramphenicol resistance cassette <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0035341#pone.0035341-Fischer2" target="_blank">[16]</a> was generated by transformation with plasmid pSO171. A polyclonal rabbit antiserum raised against CagI was used for immunoblot analysis of whole cell lysates of the P12 wild-type strain or isogenic <i>cagA</i> or <i>cagI</i> mutants. The same lysates were examined by Western blot for the presence of CagL using the polyclonal rabbit antiserum AK271. CagI and CagL protein bands, respectively, are marked by arrowheads. Note that both antisera recognize cross-reactive bands, but anti-CagI does not react with CagL or vice versa (data not shown). (C) Plasmid constructs used for generation and complementation of <i>cagI</i> mutants. A counterselection strategy was used for generating marker-free deletion mutants. Mutants generated with plasmids pWS320 and pWS326 retain the 3â€Č part of <i>cagI</i>, whereas the mutant generated with plasmid pWS327 has a complete deletion without any <i>cagI</i> traces. For complementation of <i>cagI</i> mutants <i>in trans</i>, the <i>cagI</i> gene was cloned under the control of the <i>cagA</i> promoter and integrated into the <i>recA</i> gene (plasmid pWS322).</p

    Analysis of CagI and CagL production, and of <i>cagL</i> transcription, in <i>cagI</i> mutants and complemented strains.

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    <p>(A) Whole cell lysates of the P12 wild-type strain and the indicated <i>cagI</i> mutants or complemented mutants were examined for CagI and CagL production by immunoblot analysis. Numbers in brackets indicate the plasmids used for mutant generation or complementation. (B) The indicated strains were grown in liquid culture to mid-exponential phase, and harvested for total RNA preparation and cDNA synthesis. Transcript levels of <i>cagL</i> were analyzed by quantitative real-time PCR (qPCR) and normalized to levels of 16S-rRNA for each cDNA sample. Bars represent mean values and standard deviations of <i>cagL</i> transcript levels in relation to wild-type levels for at least three independent RNA preparations.</p
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