1. |
- Aad, G, et al.
(författare)
-
- 2015
-
swepub:Mat__t
|
|
2. |
- de Graaf, M., et al.
(författare)
-
Emergence of a novel GII.17 norovirus - End of the GII.4 era?
- 2015
-
Ingår i: Eurosurveillance. - : EUR CENTRE DIS PREVENTION and CONTROL. - 1025-496X .- 1560-7917. ; 20:26, s. 21178-
-
Tidskriftsartikel (refereegranskat)abstract
- In the winter of 2014/15 a novel GII.P17-GII.17 norovirus strain (GII.17 Kawasaki 2014) emerged, as a major cause of gastroenteritis outbreaks in China and Japan. Since their emergence these novel GII.P17-GII.17 viruses have replaced the previously dominant GII.4 genotype Sydney 2012 variant in some areas in Asia but were only detected in a limited number of cases on other continents. This perspective provides an overview of the available information on GII.17 viruses in order to gain insight in the viral and host characteristics of this norovirus genotype. We further discuss the emergence of this novel GII.P17-GII.17 norovirus in context of current knowledge on the epidemiology of noroviruses. It remains to be seen if the currently dominant norovirus strain GII.4 Sydney 2012 will be replaced in other parts of the world. Nevertheless, the public health community and surveillance systems need to be prepared in case of a potential increase of norovirus activity in the next seasons caused by this novel GII.P17-GII.17 norovirus.
|
|
3. |
- Marques, W. L., et al.
(författare)
-
Combined engineering of disaccharide transport and phosphorolysis for enhanced ATP yield from sucrose fermentation in Saccharomyces cerevisiae
- 2018
-
Ingår i: Metabolic engineering. - : Academic Press Inc.. - 1096-7176 .- 1096-7184. ; 45, s. 121-133
-
Tidskriftsartikel (refereegranskat)abstract
- Anaerobic industrial fermentation processes do not require aeration and intensive mixing and the accompanying cost savings are beneficial for production of chemicals and fuels. However, the free-energy conservation of fermentative pathways is often insufficient for the production and export of the desired compounds and/or for cellular growth and maintenance. To increase free-energy conservation during fermentation of the industrially relevant disaccharide sucrose by Saccharomyces cerevisiae, we first replaced the native yeast α-glucosidases by an intracellular sucrose phosphorylase from Leuconostoc mesenteroides (LmSPase). Subsequently, we replaced the native proton-coupled sucrose uptake system by a putative sucrose facilitator from Phaseolus vulgaris (PvSUF1). The resulting strains grew anaerobically on sucrose at specific growth rates of 0.09 ± 0.02 h−1 (LmSPase) and 0.06 ± 0.01 h−1 (PvSUF1, LmSPase). Overexpression of the yeast PGM2 gene, which encodes phosphoglucomutase, increased anaerobic growth rates on sucrose of these strains to 0.23 ± 0.01 h−1 and 0.08 ± 0.00 h−1, respectively. Determination of the biomass yield in anaerobic sucrose-limited chemostat cultures was used to assess the free-energy conservation of the engineered strains. Replacement of intracellular hydrolase with a phosphorylase increased the biomass yield on sucrose by 31%. Additional replacement of the native proton-coupled sucrose uptake system by PvSUF1 increased the anaerobic biomass yield by a further 8%, resulting in an overall increase of 41%. By experimentally demonstrating an energetic benefit of the combined engineering of disaccharide uptake and cleavage, this study represents a first step towards anaerobic production of compounds whose metabolic pathways currently do not conserve sufficient free-energy.
|
|
4. |
- Juergens, H., et al.
(författare)
-
Evaluation of a novel cloud-based software platform for structured experiment design and linked data analytics
- 2018
-
Ingår i: Scientific Data. - : Nature Publishing Groups. - 2052-4463. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Open data in science requires precise definition of experimental procedures used in data generation, but traditional practices for sharing protocols and data cannot provide the required data contextualization. Here, we explore implementation, in an academic research setting, of a novel cloud-based software system designed to address this challenge. The software supports systematic definition of experimental procedures as visual processes, acquisition and analysis of primary data, and linking of data and procedures in machine-computable form. The software was tested on a set of quantitative microbial-physiology experiments. Though time-intensive, definition of experimental procedures in the software enabled much more precise, unambiguous definitions of experiments than conventional protocols. Once defined, processes were easily reusable and composable into more complex experimental flows. Automatic coupling of process definitions to experimental data enables immediate identification of correlations between procedural details, intended and unintended experimental perturbations, and experimental outcomes. Software-based experiment descriptions could ultimately replace terse and ambiguous ‘Materials and Methods’ sections in scientific journals, thus promoting reproducibility and reusability of published studies.
|
|
5. |
- Beatriz Badia, Mariana, et al.
(författare)
-
Specific Arabidopsis thaliana malic enzyme isoforms can provide anaplerotic pyruvate carboxylation function in Saccharomyces cerevisiae
- 2017
-
Ingår i: The FEBS Journal. - : WILEY. - 1742-464X .- 1742-4658. ; 284:4, s. 654-665
-
Tidskriftsartikel (refereegranskat)abstract
- NAD(P)-malic enzyme (NAD(P)-ME) catalyzes the reversible oxidative decarboxylation of malate to pyruvate, CO2, and NAD(P)H and is present as a multigene family in Arabidopsis thaliana. The carboxylation reaction catalyzed by purified recombinant Arabidopsis NADP-ME proteins is faster than those reported for other animal or plant isoforms. In contrast, no carboxylation activity could be detected in vitro for the NAD-dependent counterparts. In order to further investigate their putative carboxylating role in vivo, Arabidopsis NAD(P)-ME isoforms, as well as the NADP-ME2del2 (with a decreased ability to carboxylate pyruvate) and NADP-ME2R115A (lacking fumarate activation) versions, were functionally expressed in the cytosol of pyruvate carboxylase-negative (Pyc(-)) Saccharomyces cerevisiae strains. The heterologous expression of NADP-ME1, NADP-ME2 (and its mutant proteins), and NADP-ME3 restored the growth of Pyc(-) S. cerevisiae on glucose, and this capacity was dependent on the availability of CO2. On the other hand, NADP-ME4, NAD-ME1, and NAD-ME2 could not rescue the Pyc(-) strains from C-4 auxotrophy. NADP-ME carboxylation activity could be measured in leaf crude extracts of knockout and over-expressing Arabidopsis lines with modified levels of NADP-ME, where this activity was correlated with the amount of NADP-ME2 transcript. These results indicate that specific A. thaliana NADP-ME isoforms are able to play an anaplerotic role in vivo and provide a basis for the study on the carboxylating activity of NADP-ME, which may contribute to the synthesis of C-4 compounds and redox shuttling in plant cells.
|
|
6. |
- Håkansson, Malin, et al.
(författare)
-
Sustained lean transformation of working conditions : A Swedish longitudinal case study
- 2017
-
Ingår i: Human Factors and Ergonomics in Manufacturing. - : John Wiley & Sons. - 1090-8471 .- 1520-6564. ; 27:6, s. 268-279
-
Tidskriftsartikel (refereegranskat)abstract
- Studies of lean production’s effect on working conditions are mixed but point toward worsened conditions. The aim of this longitudinal study was to assess how lean contributes to transforming work characteristics in a medium-sized specialized industrial family business. A mixed methods approachwas used to combine an external assessment of work characteristics with selfreported employee questionnaires. Favorable psychosocial working conditions were indicated, with role conflicts decreasing over time. The assessment of work provided descriptions of how lean practices contributed to decreased task control due to standardized work and simplified work processes. At the same time, employees still had opportunities to influence their long-term work assignment. There was also a trend toward job enlargement through new, higher-skilled tasks, multiskilling, and extended opportunities to influence work through different continuous improvement activities. The participative lean approach and type of skilled jobs may have contributed to this transformation.
|
|
7. |
- Marques, Wesley Leoricy, et al.
(författare)
-
Elimination of sucrose transport and hydrolysis in Saccharomyces cerevisiae : a platform strain for engineering sucrose metabolism
- 2017
-
Ingår i: FEMS yeast research (Print). - : Oxford University Press. - 1567-1356 .- 1567-1364. ; 17:1
-
Tidskriftsartikel (refereegranskat)abstract
- Many relevant options to improve efficacy and kinetics of sucrose metabolism in Saccharomyces cerevisiae and, thereby, the economics of sucrose-based processes remain to be investigated. An essential first step is to identify all native sucrose-hydrolysing enzymes and sucrose transporters in this yeast, including those that can be activated by suppressor mutations in sucrose-negative strains. A strain in which all known sucrose-transporter genes (MAL11, MAL21, MAL31, MPH2, MPH3) were deleted did not grow on sucrose after 2 months of incubation. In contrast, a strain with deletions in genes encoding sucrose-hydrolysing enzymes (SUC2, MAL12, MAL22, MAL32) still grew on sucrose. Its specific growth rate increased from 0.08 to 0.25 h(-1) after sequential batch cultivation. This increase was accompanied by a 3-fold increase of in vitro sucrose-hydrolysis and isomaltase activities, as well as by a 3- to 5-fold upregulation of the isomaltase-encoding genes IMA1 and IMA5. One-step Cas9-mediated deletion of all isomaltase-encoding genes (IMA1-5) completely abolished sucrose hydrolysis. Even after 2 months of incubation, the resulting strain did not grow on sucrose. This sucrose-negative strain can be used as a platform to test metabolic engineering strategies and for fundamental studies into sucrose hydrolysis or transport.
|
|