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This study aimed to examine the relationship between teachers' perceived psychological distance and structural distance from management and teachers' affective organisational commitment (AOC) and organisational citizenship behaviour (OCB). Teachers' trust in management was expected to mediate these relationships. Furthermore, the adequacy and openness of communication and participation in decision making were expected to reduce psychological distance. At 10 Dutch schools for vocational education and training, 884 teachers completed a questionnaire. The data were analysed using structural equation modelling. Teachers' psychological distance had a negative effect on trust in management (supervisor and higher management) and AOC. Trust in management had a positive effect on AOC, and trust in the supervisor had a positive effect on OCB. Structural distance did not influence teacher outcomes. Communication and participation in decision making reduced teachers' psychological distance from management. The discussion focuses on the implications of the findings to improve the effectiveness of schools.

In this study we examined the role of trust as a mediator in social exchange between teachers and their school, particularly between perceived procedural justice and perceived organizational support, on the one hand, and teachers' affective organizational commitment and organizational citizenship behaviour, on the other hand. A model was developed that distinguished between trust in three agents: team members, the supervisor and higher management. The model was tested in the context of Dutch schools for vocational education and training on a sample of 845 teachers. Data was collected using questionnaires and was analysed with structural equation modelling. Results show that trust was a predictor for desirable teacher outcomes and a mediator in social exchange. In particular trust in team members was related to affective organizational commitment and organizational citizenship behaviour. Trust in the supervisor and trust in higher management were neither related to organizational commitment nor to organizational citizenship behaviour. Perceived organizational support was related to teachers' trust in all trust targets. It also had a direct effect on organizational commitment. Procedural justice influenced trust in the supervisor and trust in higher management. The authors discuss the results in light of previous findings and the context of the study.

The bacterial chalcone isomerase (CHI) from Eubacterium ramulus catalyses the first step in a flavanone-degradation pathway by a reverse Michael addition. The overall fold and the constitution of the active site of the enzyme completely differ from the well-characterised chalcone isomerase of plants. For (+)-taxifolin, CHI catalyses the intramolecular ring contraction to alphitonin. In this study, Fwe perform crystal structure analyses of CHI and its active site mutant His33Ala in the presence of the substrate taxifolin at 2.15 and 2.8 Å resolution, respectively. The inactive enzyme binds the substrate (+)-taxifolin as well defined, whereas the electron density maps of the native CHI show a superposition of substrate, product alphitonin, and most probably also the reaction intermediate taxifolin chalcone. Evidently, His33 mediates the stereospecific acid-base reaction by abstracting a proton from the flavonoid scaffold. The stereospecificity of the product is discussed. [ABSTRACT FROM AUTHOR]

The Haemophilus surface fibril (Hsf) is an unusually large trimeric autotransporter adhesin (TAA) expressed by the most virulent strains of H. influenzae. Hsf is known to mediate adhesion between pathogen and host, allowing the establishment of potentially deadly diseases such as epiglottitis, meningitis and pneumonia. While recent research has suggested that this TAA might adopt a novel `hairpin-like' architecture, the characterization of Hsf has been limited to in silico modelling and electron micrographs, with no high-resolution structural data available. Here, the crystal structure of Hsf putative domain 1 (PD1) is reported at 3.3 Å resolution. The structure corrects the previous domain annotation by revealing the presence of an unexpected N-terminal TrpRing domain. PD1 represents the first Hsf domain to be solved, and thus paves the way for further research on the `hairpin-like' hypothesis. [ABSTRACT FROM AUTHOR]

The importance of amine transaminases for producing optically pure chiral precursors for pharmaceuticals and chemicals has substantially increased in recent years. The X-ray crystal structure of the (R) -selective amine transaminase from the fungus Aspergillus fumigatus was solved by S-SAD phasing to 1.84 Å resolution. The refined structure at 1.27 A resolution provides detailed knowledge about the molecular basis of substrate recognition and conversion to facilitate protein-engineering approaches. The protein forms a homodimer and belongs to fold class IV of the pyridoxal-5'-phosphate-dependent enzymes. Both subunits contribute residues to form two active sites. The structure of the holoenzyme shows the catalytically important cofactor pyridoxal-5'-phosphate bound as an internal aldimine with the catalytically responsible amino-acid residue Lys179, as well as in its free form. A long N-terminal helix is an important feature for the stability of this fungal (R)-selective amine transaminase, but is missing in branched-chain amino-acid aminotransferases and d-amino-acid aminotransferases. [ABSTRACT FROM AUTHOR]

Flavonoide stellen eine große Gruppe pflanzlicher Sekundärmetabolite dar und haben eine Vielzahl unterschiedlicher biologischer Eigenschaften. Aufgrund dessen stehen sie im Interesse vieler Wissenschaftler, da sie zu vielen industriell interessanten Verbindungen führen können. Das anaerobe Darmbakterium Eubacterium ramulus kann über einen bislang unbekannten Abbauweg diese Flavonoide verstoffwechseln. Über eine Vollgenom ‐ Sequenzierung wurden in dieser Arbeit die entscheidenden Enzyme, eine Chalconisomerase (CHI) und eine Enoatreduktase (ERED), identifiziert, kloniert und funktionell sogar unter aeroben Bedingungen exprimiert. Mittels Biotransformation des Flavanons zum Dihydrochalcon konnte der Flavonoid ‐ Abbauweg bewiesen werden. Der beide Enzyme exprimierende E. ‐ coli ‐ Stamm kann für die Umsetzung verschiedener Flavanone eingesetzt werden. Dies unterstreicht die Anwendbarkeit des in dieser Arbeit entwickelten biokatalytischen Systems. Der biokatalytisch ‐ metabolische Weg für die Umsetzung von Flavonoiden aus Eubacterium ramulus wurde identifiziert. Eine Chalconisomerase und eine Enoatreduktase wurden erfolgreich kloniert und in E. coli exprimiert und unter aeroben Bedingungen eingesetzt, obwohl E. ramulus ein strikt anaerobes Bakterium ist. Der beide Enzyme exprimierende E. ‐ coli ‐ Stamm kann für die Umsetzung verschiedener Flavanone eingesetzt werden. [ABSTRACT FROM AUTHOR]

Flavonoids are a large group of plant secondary metabolites with a variety of biological properties and are therefore of interest to many scientists, as they can lead to industrially interesting intermediates. The anaerobic gut bacterium Eubacterium ramulus can catabolize flavonoids, but until now, the pathway has not been experimentally confirmed. In the present work, a chalcone isomerase (CHI) and an enoate reductase (ERED) could be identified through whole genome sequencing and gene motif search. These two enzymes were successfully cloned and expressed in Escherichia coli in their active form, even under aerobic conditions. The catabolic pathway of E. ramulus was confirmed by biotransformations of flavanones into dihydrochalcones. The engineered E. coli strain that expresses both enzymes was used for the conversion of several flavanones, underlining the applicability of this biocatalytic cascade reaction. [ABSTRACT FROM AUTHOR]

The ( R)-selective amine transaminase from Aspergillus fumigatus was expressed in Escherichia coli and purified to homogeneity. Bright yellow crystals appeared while storing the concentrated solution in the refrigerator and belonged to space group C2221. X-ray diffraction data were collected to 1.27 Å resolution, as well as an anomalous data set to 1.84 Å resolution that was suitable for S-SAD phasing. [ABSTRACT FROM AUTHOR]

Size-exclusion chromatography coupled to multiangle laser light scattering (SEC-MALLS) is the perfect method to determine the oligomeric state of membrane proteins as this method works in solution and is totally independent from prior assumptions such as detergent-to-protein ratio or the shape of the protein. In a relatively short time (ca. 30 min), the molecular mass and quality of a membrane protein preparation can be determined. Here, I provide a detailed protocol on how to perform a SEC-MALLS run and show exemplary chromatograms and their analysis.

Introduction: Women often develop malignant mesothelioma (MM) without occupational asbestos exposure. Northern Jutland has a high prevalence of MM due to previously high occupational exposures to asbestos. The aim of this study was to elucidate a possible domestic exposure to asbestos through first-degree relatives in women who develop MM., Material and Methods: This was a retrospective study in women with MM of the pleura. A total of 30 women were diagnosed with and treated for MM in Northern Jutland from 1996 to 2012. In all, 24 women were included. Demographic data, subtype of MM, time from first hospital contact to diagnosis, survival and information on occupational and domestic exposure to asbestos were obtained from hospital records., Results: A total of 12.5% of the study population were primarily exposed to asbestos. 46% had domestic exposure to asbestos through their husbands or sons. The median age of the study population was 66.5 years. In all, 75% suffered from the epitheloid subtype, 12.5% from the biphasic and 8.4% from the sarcomatoid subtype. Time from first hospital contact to diagnosis was one month and the median survival time was 12 months. The 1- and 5- year-survival were 58% and 0%, respectively., Conclusion: Nearly 50% of the women affected by MM have been domestically exposed to asbestos through first-degree relatives., Funding: not relevant., Trial Registration: not relevant.

In an extracorporeal combination therapy, the impact of different replacement fluids on survival was tested in a bacterial sepsis model in pigs. In an animal study 19 pigs, weighing 7.5-11.1 kg, were included. All groups received an intravenous lethal dose of live Staphylococcus aureus over 1 h. The animals were treated by an extracorporeal circuit consisting of online centrifugation and subsequent plasma filtration for 4 h. The extracorporeal circuit was pre-filled with 400 mL replacement fluid. In the P0 group 100% hydroxyethyl starch 130/0.4 was used as replacement fluid; in the P30 group 30% pig plasma and 70% hydroxyethyl starch; and in the P100 group 100% pig plasma. The observation time was 7 days. All animals of the group P100 survived, while all animals of group P0 and five out of seven animals of the P30 group died during the observation time. Extracorporeal therapy consisting of online centrifugation and plasma filtration with 100% pig plasma as replacement fluid significantly improved survival in a pig model of sepsis. Further studies with this approach are encouraged., (© 2012 The Authors. Therapeutic Apheresis and Dialysis © 2012 International Society for Apheresis.)