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Elväng, Annelie
Alternative names
Publications (8 of 8) Show all publications
Hjort, K., Presti, I., Elväng, A., Marinelli, F. & Sjöling, S. (2014). Bacterial chitinase with phytopathogen control capacity from suppressive soil revealed by functional metagenomics. Applied Microbiology and Biotechnology, 98(6), 2819-2828
Open this publication in new window or tab >>Bacterial chitinase with phytopathogen control capacity from suppressive soil revealed by functional metagenomics
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2014 (English)In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 98, no 6, p. 2819-2828Article in journal (Refereed) Published
Abstract [en]

Plant disease caused by fungal pathogens results in vast crop damage globally. Microbial communities of soil that is suppressive to fungal crop disease provide a source for the identification of novel enzymes functioning as bioshields against plant pathogens. In this study, we targeted chitin-degrading enzymes of the uncultured bacterial community through a functional metagenomics approach, using a fosmid library of a suppressive soil metagenome. We identified a novel bacterial chitinase, Chi18H8, with antifungal activity against several important crop pathogens. Sequence analyses show that the chi18H8 gene encodes a 425-amino acid protein of 46 kDa with an N-terminal signal peptide, a catalytic domain with the conserved active site F175DGIDIDWE183, and a chitinase insertion domain. Chi18H8 was expressed (pGEX-6P-3 vector) in Escherichia coli and purified. Enzyme characterization shows that Chi18H8 has a prevalent chitobiosidase activity with a maximum activity at 35 °C at pH lower than 6, suggesting a role as exochitinase on native chitin. To our knowledge, Chi18H8 is the first chitinase isolated from a metagenome library obtained in pure form and which has the potential to be used as a candidate agent for controlling fungal crop diseases. Furthermore, Chi18H8 may also answer to the demand for novel chitin-degrading enzymes for a broad range of other industrial processes and medical purposes.

Keywords
metagenomic library, chitinase, terminal restriction fragment length polymorphism (T-RFLP), Streptomycetes, suppressive soil
National Category
Microbiology Environmental Sciences
Research subject
Baltic and East European studies; Environmental Studies
Identifiers
urn:nbn:se:sh:diva-20023 (URN)10.1007/s00253-013-5287-x (DOI)000332108100041 ()24121932 (PubMedID)2-s2.0-84905997072 (Scopus ID)47/42/2011 (Local ID)47/42/2011 (Archive number)47/42/2011 (OAI)
Projects
Metaexplore - metagenomics for bioexploration
Funder
EU, FP7, Seventh Framework Programme, KBBE-222625The Foundation for Baltic and East European Studies
Note

Electronic supplementary material

Available from: 2013-10-24 Created: 2013-10-24 Last updated: 2019-03-04Bibliographically approved
Bertrand, Y., Töpel, M., Elväng, A., Melik, W. & Johansson, M. (2012). First Dating of a Recombination Event in Mammalian Tick-Borne Flaviviruses. PLoS ONE, 7(2), e31981
Open this publication in new window or tab >>First Dating of a Recombination Event in Mammalian Tick-Borne Flaviviruses
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2012 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 2, p. e31981-Article in journal (Refereed) Published
Abstract [en]

The mammalian tick-borne flavivirus group (MTBFG) contains viruses associated with important human and animal diseases such as encephalitis and hemorrhagic fever. In contrast to mosquito-borne flaviviruses where recombination events are frequent, the evolutionary dynamic within the MTBFG was believed to be essentially clonal. This assumption was challenged with the recent report of several homologous recombinations within the Tick-borne encephalitis virus (TBEV). We performed a thorough analysis of publicly available genomes in this group and found no compelling evidence for the previously identified recombinations. However, our results show for the first time that demonstrable recombination (i.e., with large statistical support and strong phylogenetic evidences) has occurred in the MTBFG, more specifically within the Louping ill virus lineage. Putative parents, recombinant strains and breakpoints were further tested for statistical significance using phylogenetic methods. We investigated the time of divergence between the recombinant and parental strains in a Bayesian framework. The recombination was estimated to have occurred during a window of 282 to 76 years before the present. By unravelling the temporal setting of the event, we adduce hypotheses about the ecological conditions that could account for the observed recombination.

National Category
Biological Sciences
Identifiers
urn:nbn:se:sh:diva-17058 (URN)10.1371/journal.pone.0031981 (DOI)000302875500062 ()2-s2.0-84857493482 (Scopus ID)
Funder
The Foundation for Baltic and East European Studies
Available from: 2012-09-13 Created: 2012-09-13 Last updated: 2018-12-17Bibliographically approved
Melik, W., Ellencrona, K., Wigerius, M., Elväng, A., Hedström, C. & Johansson, M. (2012). Two PDZ binding motifs within NS5 have roles in Tick-borne encephalitis virus replication. Virus Research, 169(1), 54-62
Open this publication in new window or tab >>Two PDZ binding motifs within NS5 have roles in Tick-borne encephalitis virus replication
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2012 (English)In: Virus Research, ISSN 0168-1702, E-ISSN 1872-7492, Vol. 169, no 1, p. 54-62Article in journal (Refereed) Published
Abstract [en]

The flavivirus genus includes important human pathogens like Tick-borne encephalitis virus (TBEV), Dengue virus (DV) and West-Nile virus (WNV), that can cause severe disease e.g. encephalitis or hemorrhagic fever. The NS5 protein is a multifunctional RNA dependent RNA polymerase indispensable for the flavivirus replication. We have previously shown that TBEVNS5 contains a unique internal PDZ binding motif (YS223) for specific targeting of the PDZ protein Scribble. This interaction has impact on both viral down regulation of host cellular defense systems and neurite outgrowth. Putative C-terminal PDZ binding motifs present in TBEVNS5 (-SII903) and WNVNS5 (-TVL905) have also previously been highlighted.

To determine whether the PDZ binding motifs of TBEVNS5 has an effect on virus replication we constructed a DNA based sub-genomic TBEV replicon expressing firefly luciferase. The motifs within NS5 were mutated individually and in concert and the replicons were assayed in cell culture. Our results show that the replication rate was impaired in all mutants, which indicates that PDZ dependent host interactions influence flavivirus replication.We also find that the C-terminal PDZ binding motif present in TBEVNS5 and WNVNS5 are targeting various human PDZ domain proteins. TBEVNS5 has high affinity to Zonulaoccludens-2 (ZO-2),GIAP C-terminus interacting protein (GIPC), Calcium/calmodulin-dependent serine protein kinase (CASK) and Interleukin 16 (IL-16).A different pattern was observed for WNVNS5 as it associated with IL-16, and several other putative interaction partners.

National Category
Biological Sciences
Research subject
Molecular Genetics
Identifiers
urn:nbn:se:sh:diva-14831 (URN)10.1016/j.virusres.2012.07.001 (DOI)000311133800008 ()22796133 (PubMedID)2-s2.0-84867223730 (Scopus ID)
Funder
The Foundation for Baltic and East European StudiesKnowledge Foundation
Note

Som manuskript i avhandling. As manuscript in dissertation.

Available from: 2011-12-22 Created: 2012-01-19 Last updated: 2017-12-08Bibliographically approved
Elväng, A., Melik, W., Bertrand, Y., Lönn, M. & Johansson, M. (2011). Sequencing of a Tick-Borne Encephalitis Virus from Ixodes ricinus Reveals a Thermosensitive RNA Switch Significant for Virus Propagation in Ectothermic Arthropods.. Vector Borne and Zoonotic Diseases, 11(6), 649-658
Open this publication in new window or tab >>Sequencing of a Tick-Borne Encephalitis Virus from Ixodes ricinus Reveals a Thermosensitive RNA Switch Significant for Virus Propagation in Ectothermic Arthropods.
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2011 (English)In: Vector Borne and Zoonotic Diseases, ISSN 1530-3667, E-ISSN 1557-7759, Vol. 11, no 6, p. 649-658Article in journal (Refereed) Published
Abstract [en]

Tick-borne encephalitis virus (TBEV) is a flavivirus with major impact on global health. The geographical TBEV distribution is expanding, thus making it pivotal to further characterize the natural virus populations. In this study, we completed the earlier partial sequencing of a TBEV pulled out of a pool of RNA extracted from 115 ticks collected on Torö in the Stockholm archipelago. The total RNA was sufficient for all sequencing of a TBEV genome (Torö-2003), without conventional enrichment procedures such as cell culturing or suckling mice amplification. To our knowledge, this is the first time that the genome of TBEV has been sequenced directly from an arthropod reservoir. The Torö-2003 sequence has been characterized and compared with other TBE viruses. In silico analyses of secondary RNA structures formed by the two untranslated regions revealed a temperature-sensitive structural shift between a closed replicative form and an open AUG accessible form, analogous to a recently described bacterial thermoswitch. Additionally, novel phylogenetic conserved structures were identified in the variable part of the 3'-untranslated region, and their sequence and structure similarity when compared with earlier identified structures suggests an enhancing function on virus replication and translation. We propose that the thermo-switch mechanism may explain the low TBEV prevalence often observed in environmentally sampled ticks. Finally, we were able to detect variations that help in the understanding of virus adaptations to varied environmental temperatures and mammalian hosts through a comparative approach that compares RNA folding dynamics between strains with different mammalian cell passage histories.

National Category
Microbiology in the medical area
Identifiers
urn:nbn:se:sh:diva-6139 (URN)10.1089/vbz.2010.0105 (DOI)000291717500010 ()21254926 (PubMedID)2-s2.0-79959411565 (Scopus ID)
Available from: 2011-02-10 Created: 2011-02-10 Last updated: 2018-01-12Bibliographically approved
Wigerius, M., Melik, W., Elväng, A. & Johansson, M. (2010). Rac1 and Scribble are targets for the arrest of neurite outgrowth by TBE virus NS5. Molecular and Cellular Neuroscience, 44(3), 260-271
Open this publication in new window or tab >>Rac1 and Scribble are targets for the arrest of neurite outgrowth by TBE virus NS5
2010 (English)In: Molecular and Cellular Neuroscience, ISSN 1044-7431, E-ISSN 1095-9327, Vol. 44, no 3, p. 260-271Article in journal (Refereed) Published
Abstract [en]

Tick-borne encephalitis virus (TBEV) causes extensive CNS disease in humans known as TBE, however, relatively little is known of the molecular mechanisms for its progress. Here, we now show that TBEV produces defects in neuronal development of PC12 cells through a function of the viral NS5 protein. The methyltransferase domain of NS5 is critical and sufficient for restriction of nerve growth factor induced neurite outgrowth. This effect is reversed by expression of NS5 mutants unable to bind Scribble and unexpectedly, in Scribble depleted cells with binding-competent NS5. Furthermore, we also demonstrate that the Rho GTPase Rac1 and the guanine nucleotide-exchange factor, beta PIX are outcompeted by NS5 for binding to Scribble, linking to effects on neurite outgrowth by TBEV. Together, these findings provide the first experimental evidence that Rac1 and beta PIX are indirect targets of NS5 acting through the multifunctional polarity protein Scribble to oppose neuronal differentiation. In conclusion, our results offer a potential mechanism by which TBEV alters neuronal circuitry and opens new avenues for therapeutic interventions.

National Category
Microbiology in the medical area
Identifiers
urn:nbn:se:sh:diva-6055 (URN)10.1016/j.mcn.2010.03.012 (DOI)000278728200006 ()20363326 (PubMedID)2-s2.0-77953231504 (Scopus ID)
Available from: 2011-02-07 Created: 2011-02-07 Last updated: 2018-01-12Bibliographically approved
Elväng, A. M., Westerberg, K., Jernberg, C. & Jansson, J. K. (2001). Use of green fluorescent protein and luciferase biomarkers to monitor survival and activity of Arthrobacter chlorophenolicus A6 cells during degradation of 4-chlorophenol in soil. Environmental Microbiology, 3(1), 32-42
Open this publication in new window or tab >>Use of green fluorescent protein and luciferase biomarkers to monitor survival and activity of Arthrobacter chlorophenolicus A6 cells during degradation of 4-chlorophenol in soil
2001 (English)In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 3, no 1, p. 32-42Article in journal (Refereed) Published
Abstract [en]

The recently isolated novel species Arthrobacter chlorophenolicus A6 is capable of growth on and degradation of high concentrations of 4-chlorophenol (up to 350 mug ml(-1)) as the sole carbon and energy source, This strain shows promise for bioremediation of environmental sites contaminated with high levels of chlorophenols. In this study, green fluorescent protein (gfp) or luciferase (luc) genes were used as biomarkers for monitoring cell number and activity, respectively, during degradation of 4-chlorophenol by A. chlorophenolicus cells. The individual marked strains, Arthrobacter chlorophenolicus A6L (luc-tagged) and Arthrobacter chlorophenolicus A6G (gfp-tagged), were monitored during degradation of 250 mug ml(-1) 4-chlorophenol in pure culture and 175 mug g(-1) 4-chlorophenol in soil microcosms. Both gene-tagged strains were capable of cleaning up the contaminated soil during 9 d incubation. During the bioremediation experiments, the luc-tagged cells were monitored using luminometry and the gfp tagged cells using flow cytometry, in addition to selective plate counting for both strains. The cells remained at high population levels in the soil (evidenced by GFP-fluorescent cell counts) and the A. chlorophenolicus A6L population was metabolically active (evidenced by luciferase activity measurements). These results demonstrate that the Arthrobacter chlorophenolicus A6 inoculum is effective for cleaning-up soil containing high concentrations of 4-chlorophenol.

National Category
Microbiology
Identifiers
urn:nbn:se:sh:diva-17374 (URN)10.1046/j.1462-2920.2001.00156.x (DOI)000167056100004 ()11225721 (PubMedID)2-s2.0-0035202047 (Scopus ID)
Available from: 2012-11-22 Created: 2012-11-19 Last updated: 2017-12-07Bibliographically approved
Westerberg, K., Elväng, A. M., Stackebrandt, E. & Jansson, J. K. (2000). Arthrobacter chlorophenolicus sp nov., a new species capable of degrading high concentrations of 4-chlorophenol. International Journal of Systematic and Evolutionary Microbiology, 50, 2083-2092
Open this publication in new window or tab >>Arthrobacter chlorophenolicus sp nov., a new species capable of degrading high concentrations of 4-chlorophenol
2000 (English)In: International Journal of Systematic and Evolutionary Microbiology, ISSN 1466-5026, E-ISSN 1466-5034, Vol. 50, p. 2083-2092Article in journal (Refereed) Published
Abstract [en]

A micro-organism was isolated from soil which could grow on high concentrations [up to 350 p.p.m. (2.7 mM)] of 4-chlorophenol (4-CP). The isolate, designated strain A6(T), was obtained from a soil suspension that had been selectively enriched with gradually increasing concentrations of 4-CP. Strain A6T could also grow on several other para-substituted phenols. Characterization of strain A6T with respect to chemical, biochemical and morphological properties, 16S rDNA sequencing and DNA-DNA hybridization indicated that the isolate is a novel species within the genus Arthrobacter for which the name Arthrobacter chlorophenolicus sp. nov. is proposed. The type strain is DSM 12829(T).

National Category
Microbiology
Identifiers
urn:nbn:se:sh:diva-15729 (URN)10.1099/00207713-50-6-2083 (DOI)000166156700016 ()11155983 (PubMedID)2-s2.0-0034519183 (Scopus ID)
Available from: 2012-03-07 Created: 2012-03-07 Last updated: 2017-12-07Bibliographically approved
Wouters, J., Elväng, A., Pawlowski, K. & Bergan, B.Sucrose synthase and glutamine synthetase expression in greenhouse cultivated Gunnera manicata forming symbiosis with Nostoc sp..
Open this publication in new window or tab >>Sucrose synthase and glutamine synthetase expression in greenhouse cultivated Gunnera manicata forming symbiosis with Nostoc sp.
(English)Manuscript (preprint) (Other academic)
National Category
Natural Sciences
Identifiers
urn:nbn:se:sh:diva-17127 (URN)
Note

Som manuskript i avhandling. As manuscript in dissertation.

Available from: 2008-01-30 Created: 2012-10-01 Last updated: 2012-10-01Bibliographically approved
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