144 research outputs found
Tietointensiivisten palvelujen rooli metsäklusterissa
Tutkimuksessa tarkastellaan tietointensiivisten palvelujen (KISA) roolia suomalaisessa metsäklusterissa. Tutkimuksen tarkoitus on selvittää metsäklusterin tietointensiivisten palvelujen käytön määrä ja luonnetta. Erityisenä tarkastelun kohteena ovat T&K sekä ICT-toiminnot. Tutkimus tarkastelee tietointensiivisten palvelujen roolia suhteessa metsäklusterin uudelleen järjestäytymiseen samalla kun se pyrkii löytämään joitakin keskeisiä piirteitä erilaisten tietointensiivisten toimintojen ja toimijoiden välisessä rajapinnassa, erityisesti innovaatioiden näkökulmasta. Tulosten mukaan metsäteollisuuden kehitystoiminta on selvästi jakautunut eri toimialoille ja erittäin suuri osa siitä tehdään panostoimittajien (kemikaalit, mineraalit etc.) sekä kone- ja laitetoimittajien piirissä. Yritysten sisäisten tietointensiivisten palvelutoimintojen (I-KISA) ja innovaatioiden merkitys on suuri, mutta eri toimialojen välisissä rahavirroissa ne sisältyvät panosten ja koneiden sekä laitteiden ostoihin. Tietointensiivisten liike-elämän palvelujen (KIBS) ja verkostoihin liittyvien tietointensiivisten palvelutoimintojen (N-KISA) merkitys on tiedonsiirtäjinä ja innovaatioiden välittäjänä kasvanut. Niitä tarvitaan myös integraattoreina, koska innovaatioilla on jalostusketjun eri osissa vaikutusta toisiinsa. Tässä integraattorin roolissa kone- ja laitevalmistajat ovat kuitenkin edelleen merkittävimpiä. – KIBS ; KISA ; metsäklusteri ; tietointensiiviset palvelutThis study employs case studies to explore the role of knowledge-intensive service activities (KISA) in the Finnish forest and related engineering and electronics industries (Forenel). Specifically, the study aims to determine the nature of these service activities and the extent to which they are used in the cluster, with a particular emphasis on ICT and R&D services. The report examines the role of KISAs in the restructuring trend found in the forest cluster. At the same time, it seeks to establish some key characteristics of the interface that lies between various KISA actors and the KISA suppliers themselves, especially in relation to innovations. According to the results, the development activities of the forest cluster are spread out across different industries and very many of them are carried out by input providers (manufacturers of chemicals and minerals, etc.) and suppliers of machinery and equipment. Internal knowledge-intensive service activities (I-KISA) and innovations are also important, but they are included in the purchases of inputs, machinery and equipment made across various industries. The significance of knowledge-intensive business services (KIBS) and networks-related, knowledge-intensive service activities (NKISA) as transferrers of knowledge and innovations has increased. These services are also needed as integrators because innovations impact each other in different stages of the production chain. Machinery and equipment manufacturers are still the most important integrators in this respect. – KIBS ; KISA ; Finnish Forest Cluster ; Knowledge Intensive Service Activit
Screening of the two-component-system histidine kinases of Listeria monocytogenes EGD-e. LiaS is needed for growth under heat, acid, alkali, osmotic, ethanol and oxidative stresses
To study the role of each two-component system (TCS) histidine kinase (HK) in stress tolerance of Listeria monocytogenes EGD-e, we monitored the growth of individual HIC deletion mutant strains under heat (42.5 degrees C), acid (pH 5.6), alkali (pH 9.4), osmotic (6% NaCl), ethanol (3.5 vol%), and oxidative (5 mM H2O2) stresses. The growth of Delta liaS (Delta lmo1021) strain was impaired under each stress, with the most notable decrease under heat and osmotic stresses. The Delta ivirS (Delta lmo1741) strain showed nearly completely restricted growth at high temperature and impaired growth in ethanol. The growth of Delta agrC (Delta lmo0050) strain was impaired under osmotic stress and slightly under oxidative stress. We successfully complemented the HIC mutations using a novel allelic exchange based approach. This approach avoided the copy-number problems associated with in trans complementation from a plasmid. The mutant phenotypes were restored to the wild-type level in the complemented strains. This study reveals novel knowledge on the HKs needed for growth of L monocytogenes EGD-e under abovementioned stress conditions, with LiaS playing multiple roles in stress tolerance of L monocytogenes EGD-e. (C) 2017 Elsevier Ltd. All rights reserved.Peer reviewe
Humans as Reservoir for Enterotoxin Gene–carrying Clostridium perfringens Type A
Humans may play a role in the transmission of gastrointestinal diseases caused by C. perfringens
Specific Isolation of Clostridium botulinum Group I Cells by Phage Lysin Cell Wall Binding Domain with the Aid of S-Layer Disruption
Clostridium botulinum is a notorious pathogen that raises health and food safety concerns by producing the potent botulinum neurotoxin and causing botulism, a potentially fatal neuroparalytic disease in humans and animals. Efficient methods for the identification and isolation of C. botulinum are warranted for laboratory diagnostics of botulism and for food safety risk assessment. The cell wall binding domains (CBD) of phage lysins are recognized by their high specificity and affinity to distinct types of bacteria, which makes them promising for the development of diagnostic tools. We previously identified CBO1751, which is the first antibotulinal phage lysin showing a lytic activity against C. botulinum Group I. In this work, we assessed the host specificity of the CBD of CBO1751 and tested its feasibility as a probe for the specific isolation of C. botulinum Group I strains. We show that the CBO1751 CBD specifically binds to C. botulinum Group I sensu lato (including C. sporogenes) strains. We also demonstrate that some C. botulinum Group I strains possess an S-layer, the disruption of which by an acid glycine treatment is required for efficient binding of the CBO1751 CBD to the cells of these strains. We further developed CBO1751 CBD-based methods using flow cytometry and magnetic separation to specifically isolate viable cells of C. botulinum Group I. These methods present potential for applications in diagnostics and risk assessment in order to control the botulism hazard
High prevalence of Clostridium botulinum in vegetarian sausages
Clostridium botulinum is a significant food safety concern due to its ability to produce highly potent neurotoxin and resistant endospores. Vegetarian sausages have become a popular source of plant protein and alternative for meat products. While vegetarian sausages have not been linked to botulism, numerous outbreaks due to preserved vegetables suggest a frequent occurrence of C. botulinum spores in the raw material. The product formulation of vegetarian sausages involves limited NaCl and preservatives, and shelf-lives may be several months. The safety of vegetarian sausages thus relies mainly on heat treatment and chilled storage. The main food safety concern is C. botulinum Group II that can grow and produce toxin at refrigeration temperatures. Here we show a high overall prevalence (32%) of C. botulinum in 74 samples of vegetarian sausages from seven producers. Both Groups I and II strains and genes for neurotoxin types A, B, E and F were detected in the products. The highest cell counts (1200 spores/kg) were observed for C. botulinum Group II in products with remaining shelf-lives of 6 months at the time of purchase. We conclude that vacuum-packaged vegetarian sausage products frequently contain C. botulinum spores and may possess a high risk of C. botulinum growth and toxin production. Chilled storage below 3°C and thorough reheating before consumption are warranted.Peer reviewe
Heat shock and prolonged heat stress attenuate neurotoxin and sporulation gene expression in group I Clostridium botulinum strain ATCC 3502
Foodborne pathogenic bacteria are exposed to a number of environmental stresses during food processing, storage, and preparation, and in the human body. In order to improve the safety of food, the understanding of molecular stress response mechanisms foodborne pathogens employ is essential. Many response mechanisms that are activated during heat shock may cross-protect bacteria against other environmental stresses. To better understand the molecular mechanisms Clostridium botulinum, the causative agent of botulism, utilizes during acute heat stress and during adaptation to stressfully high temperature, the C. botulinum Group I strain ATCC 3502 was grown in continuous culture at 39 degrees C and exposed to heat shock at 45 degrees C, followed by prolonged heat stress at 45 degrees C to allow adaptation of the culture to the high temperature. Growth in continuous culture was performed to exclude secondary growth phase effects or other environmental impacts on bacterial gene transcription. Changes in global gene expression profiles were studied using DNA microarray hybridization. During acute heat stress, Class I and III heat shock genes as well as members of the SOS regulon were activated. The neurotoxin gene botA and genes encoding the neurotoxin-associated proteins were suppressed throughout the study. Prolonged heat stress led to suppression of the sporulation machinery whereas genes related to chemotaxis and motility were activated. Induced expression of a large proportion of prophage genes was detected, suggesting an important role of acquired genes in the stress resistance of C. botulinum. Finally, changes in the expression of a large number of genes related to carbohydrate and amino acid metabolism indicated remodeling of the cellular metabolism.Peer reviewe
Sporulation Strategies and Potential Role of the Exosporium in Survival and Persistence of Clostridium botulinum
Clostridium botulinum produces the botulinum neurotoxin that causes botulism, a rare but potentially lethal paralysis. Endospores play an important role in the survival, transmission, and pathogenesis of C. botulinum. C. botulinum strains are very diverse, both genetically and ecologically. Group I strains are terrestrial, mesophilic, and produce highly heat-resistant spores, while Group II strains can be terrestrial (type B) or aquatic (type E) and are generally psychrotrophic and produce spores of moderate heat resistance. Group III strains are either terrestrial or aquatic, mesophilic or slightly thermophilic, and the heat resistance properties of their spores are poorly characterized. Here, we analyzed the sporulation dynamics in population, spore morphology, and other spore properties of 10 C. botulinum strains belonging to Groups I–III. We propose two distinct sporulation strategies used by C. botulinum Groups I–III strains, report their spore properties, and suggest a putative role for the exosporium in conferring high heat resistance. Strains within each physiological group produced spores with similar characteristics, likely reflecting adaptation to respective environmental habitats. Our work provides new information on the spores and on the population and single-cell level strategies in the sporulation of C. botulinum
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