Inactivation of DltA Modulates Virulence Factor Expression in Streptococcus pyogenes

D-alanylated lipoteichoic acid is a virtually ubiquitous component of gram-positive cell walls. Mutations in the dltABCD operon of numerous species exhibit pleiotropic effects, including reduced virulence, which has been attributed to increased binding of cationic antimicrobial peptides to the more negatively charged cell surface. In this study, we have further investigated the effects that mutating dltA has on virulence factor expression in Streptococcus pyogenes.Isogenic Delta dltA mutants had previously been created in two distinct M1T1 isolates of S. pyogenes. Immunoblots, flow cytometry, and immunofluorescence were used to quantitate M protein levels in these strains, as well as to assess their ability to bind complement. Bacteria were tested for their ability to interact with human PMN and to grow in whole human blood. Message levels for emm, sic, and various regulatory elements were assessed by quantitative RT-PCR. Cell walls of Delta dltA mutants contained much less M protein than cell walls of parent strains and this correlated with reduced levels of emm transcripts, increased deposition of complement, increased association of bacteria with polymorphonuclear leukocytes, and reduced bacterial growth in whole human blood. Transcription of at least one other gene of the mga regulon, sic, which encodes a protein that inactivates antimicrobial peptides, was also dramatically reduced in Delta dltA mutants. Concomitantly, ccpA and rofA were unaffected, while rgg and arcA were up-regulated.This study has identified a novel mechanism for the reduced virulence of dltA mutants of Streptococcus pyogenes in which gene regulatory networks somehow sense and respond to the loss of DltA and lack of D-alanine esterification of lipoteichoic acid. The mechanism remains to be determined, but the data indicate that the status of D-alanine-lipoteichoic acid can significantly influence the expression of at least some streptococcal virulence factors and provide further impetus to targeting the dlt operon of gram-positive pathogens in the search for novel antimicrobial compounds

Localism in Finland : The changing role and current crisis of the Finnish municipal system

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Kolme maaseutua - yksi trendi? : maaseutuluokitusten vertailua Etelä-Savossa

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Development of the education of open infra BIM based construction automation

Abstract This paper presents the results of the practical learning experience when combine three different school level students to learn open infrastructure building information modelling (infra BIM) and automation during OuluZone workshop week. Students started to build Speedway track in OuluZone test centre with one-week resources with the help of experts from industry and teachers. In addition, for students, ten different tricks were designed to present the tasks of the responsible person on the construction site. The idea of tricks was to teach students how these experts are using open infra BIM construction automation in their work. Infrakit, which is open infra BIM cloud service, was used to connect automation systems together. Based on the one-week workshop experience including questionnaire study answers and the results of pre-test and exam for students, it can be concluded that this type of practical learning is an effective way to teach open infra BIM based automation to students

A FRET-based high-throughput screening platform for the discovery of chemical probes targeting the scaffolding functions of human tankyrases

Abstract Tankyrases catalyse poly-ADP-ribosylation of their binding partners and the modification serves as a signal for the subsequent proteasomal degradation of these proteins. Tankyrases thereby regulate the turnover of many proteins involved in multiple and diverse cellular processes, such as mitotic spindle formation, telomere homeostasis and Wnt/β-catenin signalling. In recent years, tankyrases have become attractive targets for the development of inhibitors as potential therapeutics against cancer and fibrosis. Further, it has become clear that tankyrases are not only enzymes, but also act as scaffolding proteins forming large cellular signalling complexes. While many potent and selective tankyrase inhibitors of the poly-ADP-ribosylation function exist, the inhibition of tankyrase scaffolding functions remains scarcely explored. In this work we present a robust, simple and cost-effective high-throughput screening platform based on FRET for the discovery of small molecule probes targeting the protein–protein interactions of tankyrases. Validatory screening with the platform led to the identification of two compounds with modest binding affinity to the tankyrase 2 ARC4 domain, demonstrating the applicability of this approach. The platform will facilitate identification of small molecules binding to tankyrase ARC or SAM domains and help to advance a structure-guided development of improved chemical probes targeting tankyrase oligomerization and substrate protein interactions

On the trail of local welfare innovations in rural Finland

Final DraftIn Finland, the rural areas have been most affected by the developments threatening the survival of the welfare state as well as by conflicting efforts to save it. However, there are rural communities that have—as a response to the mainstream policy emphasizing economic efficiency and individual responsibility—developed innovative solutions to secure their welfare. Based on a case study focusing on two of such communities, these local welfare innovations are a result from a combination of external causes and local resources including the sense of community and a diverse enough community structure. The authors argue that in the context of welfare policy, the promotion of local welfare innovation calls for a comprehensive approach, which considers the broader viability dimension of the communities and works towards it in tight collaboration with various actors from different policy fields and societal sectors.peerReviewe