36 results on '"Sjollema, Klaas A."'
Search Results
2. Transient von Willebrand factor‐mediated platelet influx stimulates liver regeneration after partial hepatectomy in mice
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Kirschbaum, Marc, Jenne, Craig N., Veldhuis, Zwanida J., Sjollema, Klaas A., Lenting, Peter J., Giepmans, Ben N. G., Porte, Robert J., Kubes, Paul, Denis, Cécile V., and Lisman, Ton
- Published
- 2017
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- View/download PDF
3. FLIPPER, a combinatorial probe for correlated live imaging and electron microscopy, allows identification and quantitative analysis of various cells and organelles
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Kuipers, Jeroen, van Ham, Tjakko J., Kalicharan, Ruby D., Veenstra-Algra, Anneke, Sjollema, Klaas A., Dijk, Freark, Schnell, Ulrike, and Giepmans, Ben N. G.
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- 2015
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- View/download PDF
4. CLSM as Quantitative Method to Determine the Size of Drug Crystals in a Solid Dispersion
- Author
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de Waard, Hans, Hessels, Martin J. T., Boon, Maarten, Sjollema, Klaas A., Hinrichs, Wouter L. J., Eissens, Anko C., and Frijlink, Henderik W.
- Published
- 2011
- Full Text
- View/download PDF
5. The hydrogenosomal malic enzyme from the anaerobic fungus Neocallimastix frontalis is targeted to mitochondria of the methylotrophic yeast Hansenula polymorpha
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van der Giezen, M., Kiel, J. A. K. W., Sjollema, Klaas A., and Prins, Rudolf A.
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- 1998
- Full Text
- View/download PDF
6. Formation and maturation of parallel fiber-purkinje cell synapses in the staggerer cerebellum ex vivo
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Janmaat, Sonja, Frédéric, Florence, Sjollema, Klaas, Luiten, Paul, Mariani, Jean, and van der Want, Johannes
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- 2009
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7. Expression and cytosolic assembly of the S-layer fusion protein mSbsC-EGFP in eukaryotic cells
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Veenhuis Marten, Sjollema Klaas A, Zarschler Kristof, Blecha Andreas, and Rödel Gerhard
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Microbiology ,QR1-502 - Abstract
Abstract Background Native as well as recombinant bacterial cell surface layer (S-layer) protein of Geobacillus (G.) stearothermophilus ATCC 12980 assembles to supramolecular structures with an oblique symmetry. Upon expression in E. coli, S-layer self assembly products are formed in the cytosol. We tested the expression and assembly of a fusion protein, consisting of the mature part (aa 31–1099) of the S-layer protein and EGFP (enhanced green fluorescent protein), in eukaryotic host cells, the yeast Saccharomyces cerevisiae and human HeLa cells. Results Upon expression in E. coli the recombinant mSbsC-EGFP fusion protein was recovered from the insoluble fraction. After denaturation by Guanidine (Gua)-HCl treatment and subsequent dialysis the fusion protein assembled in solution and yielded green fluorescent cylindric structures with regular symmetry comparable to that of the authentic SbsC. For expression in the eukaryotic host Saccharomyces (S.) cerevisiae mSbsC-EGFP was cloned in a multi-copy expression vector bearing the strong constitutive GPD1 (glyceraldehyde-3-phosophate-dehydrogenase) promoter. The respective yeast transfomants were only slightly impaired in growth and exhibited a needle-like green fluorescent pattern. Transmission electron microscopy (TEM) studies revealed the presence of closely packed cylindrical structures in the cytosol with regular symmetry comparable to those obtained after in vitro recrystallization. Similar structures are observed in HeLa cells expressing mSbsC-EGFP from the Cytomegalovirus (CMV IE) promoter. Conclusion The mSbsC-EGFP fusion protein is stably expressed both in the yeast, Saccharomyces cerevisiae, and in HeLa cells. Recombinant mSbsC-EGFP combines properties of both fusion partners: it assembles both in vitro and in vivo to cylindrical structures that show an intensive green fluorescence. Fusion of proteins to S-layer proteins may be a useful tool for high level expression in yeast and HeLa cells of otherwise instable proteins in their native conformation. In addition the self assembly properties of the fusion proteins allow their simple purification. Moreover the binding properties of the S-layer part can be used to immobilize the fusion proteins to various surfaces. Arrays of highly ordered and densely structured proteins either immobilized on surfaces or within living cells may be advantageous over the respective soluble variants with respect to stability and their potential interference with cellular metabolism.
- Published
- 2005
- Full Text
- View/download PDF
8. Particle Bombardment of Ex Vivo Skin to Deliver DNA and Express Proteins
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Sokol, Ena, Nijenhuis, Miranda, Sjollema, Klaas A, Jonkman, Marcel F, Pas, Hendri H, Giepmans, Ben N G, Clausen, Björn E., Laman, Jon D., Translational Immunology Groningen (TRIGR), Microbes in Health and Disease (MHD), Center for Liver, Digestive and Metabolic Diseases (CLDM), and Basic and Translational Research and Imaging Methodology Development in Groningen (BRIDGE)
- Subjects
0301 basic medicine ,Human skin ,Transfection ,Biology ,Molecular biology ,Green fluorescent protein ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,Plasmid ,chemistry ,Live cell imaging ,Complementary DNA ,Biophysics ,Ex vivo ,DNA - Abstract
Particle bombardment of gold microparticles coated with plasmids, which are accelerated to high velocity, is used for transfection of cells within tissue. Using this method, cDNA encoding proteins of interest introduced into ex vivo living human skin enables studying of proteins of interest in real time. Here, technical aspects of particle bombardment of ex vivo skin are described using green fluorescent protein (GFP) as readout for efficiency. This method can be applied on numerous tissues, including in living model animals.
- Published
- 2017
9. PS13 - 65. Correlated microscopy and nanotomy to analyze complete cross sections of Islets of Langerhans in Type I diabetes
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Giepmans, Ben, Kalicharan, Ruby, Sjollema, Klaas, Dijk, Freark, Visser, Jeroen, Avramut, Cristina, Koster, Bram, Faas, Frank, and Ravelli, Raimond
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- 2011
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10. An improved method for light- and electron microscopial studies of nematode/fungal interactions
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Veenhuis, Marten, Sjollema, Klaas, Nordbring-Hertz, Birgit, and Harder, Wim
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- 1989
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11. Expression and cytosolic assembly of the S-layer fusion protein mSbsC-EGFP in eukaryotic cells
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Blecha, Andreas, Zarschler, Kristof, Sjollema, Klaas A., Veenhuis, Marten, Rödel, Gerhard, Rodel, G., and Molecular Cell Biology
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biology ,Research ,Saccharomyces cerevisiae ,lcsh:QR1-502 ,Bioengineering ,biology.organism_classification ,BACILLUS-STEAROTHERMOPHILUS ATCC-12980 ,GENE ,Applied Microbiology and Biotechnology ,Fusion protein ,Yeast ,lcsh:Microbiology ,Green fluorescent protein ,law.invention ,CLONING ,SBSC ,Cytosol ,Biochemistry ,law ,Recombinant DNA ,CHAIN ,NRS 2004/3A ,Gene ,S-layer ,Biotechnology - Abstract
Background Native as well as recombinant bacterial cell surface layer (S-layer) protein of Geobacillus (G.) stearothermophilus ATCC 12980 assembles to supramolecular structures with an oblique symmetry. Upon expression in E. coli, S-layer self assembly products are formed in the cytosol. We tested the expression and assembly of a fusion protein, consisting of the mature part (aa 31–1099) of the S-layer protein and EGFP (enhanced green fluorescent protein), in eukaryotic host cells, the yeast Saccharomyces cerevisiae and human HeLa cells. Results Upon expression in E. coli the recombinant mSbsC-EGFP fusion protein was recovered from the insoluble fraction. After denaturation by Guanidine (Gua)-HCl treatment and subsequent dialysis the fusion protein assembled in solution and yielded green fluorescent cylindric structures with regular symmetry comparable to that of the authentic SbsC. For expression in the eukaryotic host Saccharomyces (S.) cerevisiae mSbsC-EGFP was cloned in a multi-copy expression vector bearing the strong constitutive GPD 1 (glyceraldehyde-3-phosophate-dehydrogenase) promoter. The respective yeast transfomants were only slightly impaired in growth and exhibited a needle-like green fluorescent pattern. Transmission electron microscopy (TEM) studies revealed the presence of closely packed cylindrical structures in the cytosol with regular symmetry comparable to those obtained after in vitro recrystallization. Similar structures are observed in HeLa cells expressing mSbsC-EGFP from the Cytomegalovirus (CMV IE) promoter. Conclusion The mSbsC-EGFP fusion protein is stably expressed both in the yeast, Saccharomyces cerevisiae, and in HeLa cells. Recombinant mSbsC-EGFP combines properties of both fusion partners: it assembles both in vitro and in vivo to cylindrical structures that show an intensive green fluorescence. Fusion of proteins to S-layer proteins may be a useful tool for high level expression in yeast and HeLa cells of otherwise instable proteins in their native conformation. In addition the self assembly properties of the fusion proteins allow their simple purification. Moreover the binding properties of the S-layer part can be used to immobilize the fusion proteins to various surfaces. Arrays of highly ordered and densely structured proteins either immobilized on surfaces or within living cells may be advantageous over the respective soluble variants with respect to stability and their potential interference with cellular metabolism.
- Published
- 2005
12. Effect of UV B on cell characteristics of the marine diatom Cyclotella sp
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Buma, Anita, Zemmelink, Henk J, Sjollema, Klaas A, Gieskes, Winfried W.C., Bauer, H, Nolan, C, and Ocean Ecosystems
- Published
- 1995
13. Proteinuria Triggers Renal Lymphangiogenesis Prior to the Development of Interstitial Fibrosis.
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Yazdani, Saleh, Poosti, Fariba, Kramer, Andrea B., Mirković, Katarina, Kwakernaak, Arjan J., Hovingh, Menno, Slagman, Maartje C. J., Sjollema, Klaas A., de Borst, Martin H., Navis, Gerjan, van Goor, Harry, and van den Born, Jacob
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TUBERCULOSIS diagnosis ,MEDICAL imaging systems ,CLINICAL trials ,MICROSCOPY ,FLUORESCENCE microscopy - Abstract
Proteinuria is an important cause of progressive tubulo-interstitial damage. Whether proteinuria could trigger a renal lymphangiogenic response has not been established. Moreover, the temporal relationship between development of fibrosis, inflammation and lymphangiogenesis in chronic progressive kidney disease is not clear yet. Therefore, we evaluated the time course of lymph vessel (LV) formation in relation to proteinuria and interstitial damage in a rat model of chronic unilateral adriamycin nephrosis. Proteinuria and kidneys were evaluated up to 30 weeks after induction of nephrosis. LVs were identified by podoplanin/VEGFR3 double staining. After 6 weeks proteinuria was well-established, without influx of interstitial macrophages and myofibroblasts, collagen deposition, osteopontin expression (tubular activation) or LV formation. At 12 weeks, a ~3-fold increase in cortical LV density was found (p <0.001), gradually increasing over time. This corresponded with a significant increase in tubular osteopontin expression (p<0.01) and interstitial myofibroblast numbers (p<0.05), whereas collagen deposition and macrophage numbers were not yet increased. VEGF-C was mostly expressed by tubular cells rather than interstitial cells. Cultured tubular cells stimulated with FCS showed a dose-dependent increase in mRNA and protein expression of VEGF-C which was not observed by human albumin stimulation. We conclude that chronic proteinuria provoked lymphangiogenesis in temporal conjunction with tubular osteopontin expression and influx of myofibroblasts, that preceded interstitial fibrosis. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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14. Immunolabeling artifacts and the need for live-cell imaging.
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Schnell, Ulrike, Dijk, Freark, Sjollema, Klaas A, and Giepmans, Ben N G
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SINGLE cell proteins ,PROTEIN analysis ,IMMUNOGLOBULINS ,IMMUNOFLUORESCENCE ,IMMUNOLOGY technique - Abstract
Fluorescent fusion proteins have revolutionized examination of proteins in living cells. Still, studies using these proteins are met with criticism because proteins are modified and ectopically expressed, in contrast to immunofluorescence studies. However, introducing immunoreagents inside cells can cause protein extraction or relocalization, not reflecting the in vivo situation. Here we discuss pitfalls of immunofluorescence labeling that often receive little attention and argue that immunostaining experiments in dead, permeabilized cells should be complemented with live-cell imaging when scrutinizing protein localization. [ABSTRACT FROM AUTHOR]
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- 2012
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15. CLSM as Quantitative Method to Determine the Size of Drug Crystals in a Solid Dispersion.
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Waard, Hans, Hessels, Martin, Boon, Maarten, Sjollema, Klaas, Hinrichs, Wouter, Eissens, Anko, and Frijlink, Henderik
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DRUG analysis ,DISPERSION (Chemistry) ,MICROSCOPY ,CRYSTALS ,DIPYRIDAMOLE ,FREEZE-drying ,CRYSTALLIZATION ,OPTICAL diffraction ,PARTICLE size determination - Abstract
Purpose: To test whether confocal laser scanning microscopy (CLSM) can be used as an analytical tool to determine the drug crystal size in a powder mixture or a crystalline solid dispersion. Methods: Crystals of the autofluorescent drug dipyridamole were incorporated in a matrix of crystalline mannitol by physical mixing or freeze-drying. Laser diffraction analysis and dissolution testing were used to validate the particle size that was found by CLSM. Results: The particle size of the pure drug as determined by laser diffraction and CLSM were similar (D of approximately 22 μm). CLSM showed that the dipyridamole crystals in the crystalline dispersion obtained by freeze-drying of less concentrated solutions were of sub-micron size (0.7 μm), whereas the crystals obtained by freeze-drying of more concentrated solutions were larger (1.3 μm). This trend in drug crystal size was in agreement with the dissolution behavior of the tablets prepared from these products. Conclusion: CLSM is a useful technique to determine the particle size in a powder mixture. Furthermore, CLSM can be used to determine the drug crystal size over a broad size distribution. A limitation of the method is that the drug should be autofluorescent. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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16. Differential Effects of TNF (TNFSF2) and IFN-c on Intestinal Epithelial Cell Morphogenesis and Barrier Function in Three-Dimensional Culture.
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Juuti-Uusitalo, Kati, Klunder, Leon J., Sjollema, Klaas A., Mackovicova, Katarina, Ohgaki, Ryuichi, Hoekstra, Dick, Dekker, Jan, and van IJzendoorn, Sven C. D.
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TUMOR necrosis factors ,CYTOKINES ,EPITHELIAL cells ,MORPHOGENESIS ,INFLAMMATORY bowel diseases ,INFLIXIMAB ,CASPASES ,CELL culture - Abstract
Background: The cytokines TNF (TNFSF2) and IFN&ggr; are important mediators of inflammatory bowel diseases and contribute to enhanced intestinal epithelial permeability by stimulating apoptosis and/or disrupting tight junctions. Apoptosis and tight junctions are also important for epithelial tissue morphogenesis, but the effect of TNF and IFN&ggr; on the process of intestinal epithelial morphogenesis is unknown. Methods/Principal Findings: We have employed a three-dimensional cell culture system, reproducing in vivo-like multicellular organization of intestinal epithelial cells, to study the effect of TNF on intestinal epithelial morphogenesis and permeability. We show that human intestinal epithelial cells in three-dimensional culture assembled into luminal spheres consisting of a single layer of cells with structural, internal, and planar cell polarity. Exposure of preformed luminal spheres to TNF or IFN&ggr; enhanced paracellular permeability, but via distinctive mechanisms. Thus, while both TNF and IFN&ggr;, albeit in a distinguishable manner, induced the displacement of selected tight junction proteins, only TNF increased paracellular permeability via caspase-driven apoptosis and cell shedding. Infliximab and adalumimab inhibited these effects of TNF. Moreover, we demonstrate that TNF via its stimulatory effect on apoptosis fundamentally alters the process of intestinal epithelial morphogenesis, which contributes to the de novo generation of intestinal epithelial monolayers with increased permeability. Also IFN&ggr; contributes to the de novo formation of monolayers with increased permeability, but in a manner that does not involve apoptosis. Conclusions: Our study provides an optimized 3D model system for the integrated analysis of (real-time) intestinal epithelial paracellular permeability and morphogenesis, and reveals apoptosis as a pivotal mechanism underlying the enhanced permeability and altered morphogenesis in response to TNF, but not IFN&ggr;. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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17. Expression, transport, and axonal sorting of neuronal CCL21 in large dense-core vesicles.
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de Jong, Eiko K., Vinet, Jonathan, Stanulovic, Vesna S., Meijer, Michel, Wesseling, Evelyn, Sjollema, Klaas, Boddeke, Hendrikus W. G. M., and Biber, Knut
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NEURONS ,NEUROIMMUNOLOGY ,CHEMOKINES ,MICROGLIA ,AXONS - Abstract
Neurons are highly polarized cells, and neuron-neuron communication is based on directed transport and release of neurotransmitters, neuropeptides, and neurotrophins. Directed communication may also be attributed to neuron-microglia signaling, since neuronal damage can induce a microglia reaction at specific sites only. However, the mechanism underlying this site-specific microglia reaction is not yet understood. Neuronal CCL21 is a microglia-activating chemokine, which in brain is solely found in endangered neurons and is therefore a candidate for neuronmicroglia signaling. Here we present that neuronal CCL21 is sorted into large dense-core vesicles, the secretory granules of the regulated release pathway of neurons. Live-cell imaging studies show preferential sorting of CCL21-containing vesicles into axons, indicating its directed transport. Thus, mouse neurons express and transport a microglia activating factor very similar to signaling molecules used in neuron-neuron communication. These data show for the first time the directed transport of a microglia activating factor in neurons and corroborate the function of neuronal CCL21 in directed neuron-microglia communication. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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18. Nitrate-dependent [Fe(II)EDTA]2− oxidation by Paracoccus ferrooxidans sp. nov., isolated from a denitrifying bioreactor.
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Kumaraswamy, Rajkumari, Sjollema, Klaas, Kuenen, Gijs, van Loosdrecht, Mark, and Muyzer, Gerard
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ETHYLENEDIAMINETETRAACETIC acid ,DENITRIFICATION ,RNA ,DENITRIFYING bacteria ,ELECTRON donor-acceptor complexes ,BIOREACTORS - Abstract
Abstract: Enrichments with [Fe(II)EDTA]
2− as electron donor and nitrate or nitrite as electron acceptor were established using an inoculum from a bioreactor performing denitrification. A nitrate-reducing, [Fe(II)EDTA]2− oxidizing strain was isolated and named strain BDN-1. The G+C content of strain BDN-1 was 67%, and the organism was closely affiliated to Paracoccus denitrificans, P. pantotrophus and P. versutus by 16S rRNA sequence comparison. Results from DNA–DNA hybridization, rep-PCR, and whole cell protein analysis gave congruent results confirming the genotypic and phenotypic differences between strain BDN-1 and the other species of Paracoccus. From these results, we considered strain BDN-1 as a novel species for which we propose the name Paracoccus ferrooxidans. Apart from [Fe(II)EDTA]2− , BDN-1 could also use thiosulfate and thiocyanate as inorganic electron donors. Nitrate, nitrite, N2 O, [Fe(II)EDTA·NO]2− and oxygen could be used by strain BDN-1 as electron acceptors. Repeated transfer on a culture medium with bicarbonate as the sole carbon source confirmed that strain BDN-1 was a facultative autotroph. [Fe(II)EDTA]2− oxidation dependent denitrification was also performed by other Paracoccus species, that were closely affiliated to P. ferrooxidans. [Copyright &y& Elsevier]- Published
- 2006
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19. Microautophagy and macropexophagy may occur simultaneously in Hansenula polymorpha
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Monastryska, Iryna, Sjollema, Klaas, van der Klei, Ida J., Kiel, Jan A.K.W., and Veenhuis, Marten
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- *
NITROGEN , *PEROXISOMES , *YEAST , *GLUCOSE - Abstract
We subjected methanol-grown cells of wild type Hansenula polymorpha simultaneously to nitrogen depletion and excess glucose conditions. Both treatments induce the degradation of peroxisomes, either selective (via excess glucose) or non-selective (via nitrogen limitation). Our combined data strongly suggest that both processes occur simultaneously under these conditions. The implications of these findings on studies of autophagy and related transport pathways to the vacuole in yeast are discussed. [Copyright &y& Elsevier]
- Published
- 2004
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20. Detergent-Mediated Reconstitution of Membrane Proteins.
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Knol, Jan and Sjollema, Klaas
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MEMBRANE proteins , *LIPOSOMES - Abstract
Discusses a study on the detergent-mediated reconstitution of membrane proteins. Bacterial strains and growth conditions; Titrations of liposomes with detergent; Cryotransmission electron microscopy; Results and discussion.
- Published
- 1998
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21. A cytoplasmic lectin produced by the fungus Arthrobotrys oligospora functions as a storage...
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Rosen, Stefan and Sjollema, Klaas
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ARTHROBOTRYS - Abstract
Investigates the localization and expression of AOL in Arthrobotrys oligospora. Methodology utilized in the study; Results and conclusion of the study; Production of AOL in liquid cultures; Information on the AOL.
- Published
- 1997
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22. How antibodies alter the cell entry pathway of dengue virus particles in macrophages.
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Ayala-Nunez, Nilda V., Hoornweg, Tabitha E., van de Pol, Denise P.I., Sjollema, Klaas A., Flipse, Jacky, van der Schaar, Hilde M., and Smit, Jolanda M.
- Published
- 2016
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- View/download PDF
23. Entry of PIP3-containing polyplexes into MDCK epithelial cells by local apical-basal polarity reversal.
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Wang, Cuifeng, de Jong, Edwin, Sjollema, Klaas A., and Zuhorn, Inge S.
- Published
- 2016
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24. Dynamin-related proteins Vps1p and Dnm1p control peroxisome abundance in Saccharomyces cerevisiae.
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Kuravi, Kasinath, Nagotu, Shirisha, Krikken, Arjen M., Sjollema, Klaas, Deckers, Markus, Erdmann, Ralf, Veenhuis, Marten, and Van Der Klei, Ida J.
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DYNAMIN (Genetics) ,SACCHAROMYCES cerevisiae ,CELLS ,PROTEINS ,GLUCOSE ,PEROXISOMES ,FLUORESCENCE microscopy ,CELL division - Abstract
Saccharomyces cerevisiae contains three dynamin-related-proteins, Vps1p, Dnm1p and Mgm1p. Previous data from glucose-grown VPS1 and DNM1 null mutants suggested that Vps1p, but not Dnm1p, plays a role in regulating peroxisome abundance. Here we show that deletion of DNM1 also results in reduction of peroxisome numbers. This was not observed in glucose-grown dnm1 cells, but was evident in cells grown in the presence of oleate. Similar observations were made in cells lacking Fis1p, a protein involved in Dnm1p function. Fluorescence microscopy of cells producing Dnm1-GFP or GFP-Fis1p demonstrated that both proteins had a dual localization on mitochondria and peroxisomes. Quantitative analysis revealed a greater reduction in peroxisome number in oleate-induced vps1 cells relative to dnm1 or fis1 cells. A significant fraction of oleate-induced vps1 cells still contained two or more peroxisomes. Conversely, almost all cells of a dnm1 vps1 double-deletion strain contained only one, enlarged peroxisome. This suggests that deletion of DNM1 reinforces the vps1 peroxisome phenotype. Time-lapse imaging indicated that during budding of dnm1 vps1 cells, the single peroxisome present in the mother cell formed long protrusions into the developing bud. This organelle divided at a very late stage of the budding process, possibly during cytokinesis. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
25. Subcellular localization of vanillyl-alcohol oxidase in Penicillium simplicissimum
- Author
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Fraaije, Marco W, Sjollema, Klaas A, Veenhuis, Marten, and van Berkel, Willem J.H
- Published
- 1998
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26. Hydrogenosomes in the anaerobic fungus Neocallimastix frontalis have a double membrane but lack an associated organelle genome
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van der Giezen, Mark, Sjollema, Klaas A, Artz, Rebekka R.E, Alkema, Wynand, and Prins, Rudolf A
- Published
- 1997
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27. The unprocessed preprotein form IATC103S of the isopenicillin N acyltransferase is transported inside peroxisomes and regulates its self-processing
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García-Estrada, Carlos, Vaca, Inmaculada, Fierro, Francisco, Sjollema, Klaas, Veenhuis, Marten, and Martín, Juan Francisco
- Subjects
- *
ACYLTRANSFERASES , *TRANSFERASES , *PEROXISOMES , *MICROBODIES - Abstract
Abstract: Previous studies in Penicillium chrysogenum and Aspergillus nidulans suggested that self-processing of the isopenicillin N acyltransferase (IAT) is an important differential factor in these fungi. Expression of a mutant penDE C103S gene in P. chrysogenum gave rise to an unprocessed inactive variant of IAT (IATC103S) located inside peroxisomes, which indicates that transport of the proIAT inside these organelles is not dependent on the processing state of the protein. Co-expression of the penDE C103S and wild-type penDE genes in P. chrysogenum (Wis54-DE C103S strain) led to a decrease in benzylpenicillin levels. Changes in the wild-type IAT processing profile (β subunit formation) were observed in the Wis54-DE C103S strain, suggesting a regulatory role of the unprocessed IATC103S in the processing of the wild-type IAT. This was confirmed in Escherichia coli, where a delay in the processing of IAT in presence of the unprocessable IAT C103S was observed. Our results indicate that IAT is post-translationally regulated by its preprotein, which interferes with the self-processing. [Copyright &y& Elsevier]
- Published
- 2008
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28. <f>δ</f>-(l-<f>α</f>-Aminoadipyl)-l-cysteinyl-d-valine synthetase, that mediates the first committed step in penicillin biosynthesis, is a cytosolic enzyme
- Author
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van der Lende, Ted R., van de Kamp, Mart, Berg, Marco van den, Sjollema, Klaas, Bovenberg, Roel A.L., Veenhuis, Marten, Konings, Wil N., and Driessen, Arnold J.M.
- Subjects
- *
PENICILLIN , *BETA lactam antibiotics - Abstract
Penicillin biosynthesis by Penicillium chrysogenum is a compartmentalized process. The first catalytic step is mediated by
δ -(l-α -aminoadipyl)-l-cysteinyl-d-valine synthetase (ACV synthetase), a high molecular mass enzyme that condenses the amino acids l-α -aminoadipate, l-cysteine, and l-valine into the tripeptide ACV. ACV synthetase has previously been localized to the vacuole where it is thought to utilize amino acids from the vacuolar pools. We localized ACV synthetase by subcellular fractionation and immuno-electron microscopy under conditions that prevented proteolysis and found it to co-localize with isopenicillin N synthetase in the cytosol, while acyltransferase localizes in microbodies. These data imply that the key enzymatic steps in penicillin biosynthesis are confined to only two compartments, i.e., the cytosol and microbody. [Copyright &y& Elsevier]- Published
- 2002
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29. Particle Bombardment of Ex Vivo Skin to Deliver DNA and Express Proteins.
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Sokol E, Nijenhuis M, Sjollema KA, Jonkman MF, Pas HH, and Giepmans BNG
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- Animals, Biolistics instrumentation, DNA, Complementary genetics, DNA, Complementary metabolism, Gene Expression, Genes, Reporter, Gold chemistry, Green Fluorescent Proteins metabolism, Helium, Humans, Microspheres, Particle Size, Plasmids chemistry, Spectrometry, Fluorescence, Biolistics methods, Green Fluorescent Proteins genetics, Plasmids metabolism, Skin metabolism, Tissue Culture Techniques methods
- Abstract
Particle bombardment of gold microparticles coated with plasmids, which are accelerated to high velocity, is used for transfection of cells within tissue. Using this method, cDNA encoding proteins of interest introduced into ex vivo living human skin enables studying of proteins of interest in real time. Here, technical aspects of particle bombardment of ex vivo skin are described using green fluorescent protein (GFP) as readout for efficiency. This method can be applied on numerous tissues, including in living model animals.
- Published
- 2017
- Full Text
- View/download PDF
30. Intravital correlated microscopy reveals differential macrophage and microglial dynamics during resolution of neuroinflammation.
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van Ham TJ, Brady CA, Kalicharan RD, Oosterhof N, Kuipers J, Veenstra-Algra A, Sjollema KA, Peterson RT, Kampinga HH, and Giepmans BN
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- Animals, Apolipoproteins E metabolism, Astrocytes pathology, Brain ultrastructure, Cell Count, Cell Death, Green Fluorescent Proteins metabolism, Larva, Membrane Glycoproteins metabolism, Microfilament Proteins metabolism, Microglia ultrastructure, Neurons pathology, Neutrophils pathology, Phagocytes pathology, Phagocytes ultrastructure, Phagocytosis, Time Factors, Zebrafish, Brain pathology, Inflammation pathology, Macrophages pathology, Microglia pathology, Microscopy methods
- Abstract
Many brain diseases involve activation of resident and peripheral immune cells to clear damaged and dying neurons. Which immune cells respond in what way to cues related to brain disease, however, remains poorly understood. To elucidate these in vivo immunological events in response to brain cell death we used genetically targeted cell ablation in zebrafish. Using intravital microscopy and large-scale electron microscopy, we defined the kinetics and nature of immune responses immediately following injury. Initially, clearance of dead cells occurs by mononuclear phagocytes, including resident microglia and macrophages of peripheral origin, whereas amoeboid microglia are exclusively involved at a later stage. Granulocytes, on the other hand, do not migrate towards the injury. Remarkably, following clearance, phagocyte numbers decrease, partly by phagocyte cell death and subsequent engulfment of phagocyte corpses by microglia. Here, we identify differential temporal involvement of microglia and peripheral macrophages in clearance of dead cells in the brain, revealing the chronological sequence of events in neuroinflammatory resolution. Remarkably, recruited phagocytes undergo cell death and are engulfed by microglia. Because adult zebrafish treated at the larval stage lack signs of pathology, it is likely that this mode of resolving immune responses in brain contributes to full tissue recovery. Therefore, these findings suggest that control of such immune cell behavior could benefit recovery from neuronal damage., (© 2014. Published by The Company of Biologists Ltd.)
- Published
- 2014
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31. Destruction of tissue, cells and organelles in type 1 diabetic rats presented at macromolecular resolution.
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Ravelli RB, Kalicharan RD, Avramut MC, Sjollema KA, Pronk JW, Dijk F, Koster AJ, Visser JT, Faas FG, and Giepmans BN
- Subjects
- Animals, Cell Nucleolus metabolism, Cell Nucleolus pathology, Cell Nucleolus ultrastructure, Diabetes Mellitus, Experimental metabolism, Diabetes Mellitus, Type 1 metabolism, Disease Progression, Endocrine Cells metabolism, Endocrine Cells pathology, Endocrine Cells ultrastructure, Endoplasmic Reticulum Stress physiology, Erythrocytes metabolism, Erythrocytes pathology, Erythrocytes ultrastructure, Glycogen metabolism, Granulocytes metabolism, Granulocytes pathology, Granulocytes ultrastructure, Insulin metabolism, Insulin-Secreting Cells metabolism, Insulin-Secreting Cells pathology, Insulin-Secreting Cells ultrastructure, Islets of Langerhans metabolism, Islets of Langerhans ultrastructure, Leukocytes metabolism, Leukocytes pathology, Leukocytes ultrastructure, Microscopy, Electron methods, Rats, Diabetes Mellitus, Experimental pathology, Diabetes Mellitus, Type 1 pathology, Islets of Langerhans pathology
- Abstract
Finding alternatives for insulin therapy and making advances in etiology of type 1 diabetes benefits from a full structural and functional insight into Islets of Langerhans. Electron microscopy (EM) can visualize Islet morphology at the highest possible resolution, however, conventional EM only provides biased snapshots and lacks context. We developed and employed large scale EM and compiled a resource of complete cross sections of rat Islets during immuno-destruction to provide unbiased structural insight of thousands of cells at macromolecular resolution. The resource includes six datasets, totalling 25.000 micrographs, annotated for cellular and ultrastructural changes during autoimmune diabetes. Granulocytes are attracted to the endocrine tissue, followed by extravasation of a pleiotrophy of leukocytes. Subcellullar changes in beta cells include endoplasmic reticulum stress, insulin degranulation and glycogen accumulation. Rare findings include erythrocyte extravasation and nuclear actin-like fibers. While we focus on a rat model of autoimmune diabetes, our approach is general applicable.
- Published
- 2013
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32. Nonviral gene delivery vectors use syndecan-dependent transport mechanisms in filopodia to reach the cell surface.
- Author
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ur Rehman Z, Sjollema KA, Kuipers J, Hoekstra D, and Zuhorn IS
- Subjects
- Nanocapsules ultrastructure, DNA administration & dosage, DNA genetics, Genetic Vectors genetics, Nanocapsules chemistry, Pseudopodia genetics, Syndecans chemistry, Transfection methods
- Abstract
Lipoplexes and polyplexes, that is, assemblies of cationic lipids and polymers with nucleic acids, respectively, are popular nanocarriers for delivery of genes or siRNA into cells for therapeutic or cell biological purposes. Although endocytosis represents a major mechanism for their cellular entry, very little is known about parameters that govern early events in the initial interaction of such delivery devices with the cell surface. Here, we demonstrate that prior to entry, poly- and lipoplexes are captured by thin, actin-rich filopodial extensions, protruding from the cell surface. Subsequent additional recruitment and local clustering of filopodia-localized syndecans, presumably driven by multivalent interactions with the polycationic nanocarriers, appear instrumental in their processing to the cell body. Detailed microscopic analyses reveal that the latter relies on either directional surfing along or retraction of the filopodia. By interfering with actin polymerization or inhibiting the motor protein myosin II, localized at the base of filopodia, our data reveal that the binding of the nanocarriers to and subsequent clustering of syndecans initiates actin retrograde flow, which moves the syndecan-bound nanocarriers to the cell body. At the present experimental conditions, inhibition of this process inhibits nanocarrier-mediated transfection by 50-90%. The present findings add novel insight to our understanding of the mechanism of nanocarrier-cell surface interaction, which may be instrumental in further improving delivery efficiency. In addition, the current experimental approach may also be of relevance to improving our understanding of cellular infection by viruses and pathogenic bacteria, given a striking parallel in filopodia-mediated processing of these infectious particles and nanocarriers.
- Published
- 2012
- Full Text
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33. Correlated light microscopy and electron microscopy.
- Author
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Sjollema KA, Schnell U, Kuipers J, Kalicharan R, and Giepmans BN
- Subjects
- Animals, Cells, Cultured, Fluorescent Dyes chemistry, Humans, Image Processing, Computer-Assisted, Microscopy, Electron, Scanning, Microscopy, Fluorescence, Microtomy, Single-Cell Analysis, Staining and Labeling, Microscopy, Electron, Transmission
- Abstract
Understanding where, when, and how biomolecules (inter)act is crucial to uncover fundamental mechanisms in cell biology. Recent developments in fluorescence light microscopy (FLM) allow protein imaging in living cells and at the near molecular level. However, fluorescence microscopy only reveals selected biomolecules or organelles but not the (ultra)structural context, as can be examined by electron microscopy (EM). LM and EM of the same cells, so-called correlative (or correlated) light and electron microscopy (CLEM), allow examining rare or dynamic events first by LM, and subsequently by EM. Here, we review progress in CLEM, with focus on matching the areas between different microscopic modalities. Moreover, we introduce a method that includes a virtual overlay and automated large-scale imaging, allowing to switch between most microscopes. Ongoing developments will revolutionize and standardize CLEM in the near future, which thus holds great promise to become a routine technique in cell biology., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
34. Differential effects of TNF (TNFSF2) and IFN-γ on intestinal epithelial cell morphogenesis and barrier function in three-dimensional culture.
- Author
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Juuti-Uusitalo K, Klunder LJ, Sjollema KA, Mackovicova K, Ohgaki R, Hoekstra D, Dekker J, and van Ijzendoorn SC
- Subjects
- Adalimumab, Antibodies, Monoclonal pharmacology, Antibodies, Monoclonal, Humanized pharmacology, Apoptosis drug effects, Caco-2 Cells, Cell Membrane Permeability drug effects, Cell Polarity drug effects, Epithelial Cells metabolism, Epithelial Cells ultrastructure, Extracellular Space drug effects, Extracellular Space metabolism, Humans, Infliximab, Mitotic Index, Models, Biological, Protein Transport drug effects, Subcellular Fractions drug effects, Subcellular Fractions metabolism, Tight Junctions drug effects, Tight Junctions metabolism, Cell Culture Techniques methods, Epithelial Cells cytology, Epithelial Cells drug effects, Interferon-gamma pharmacology, Intestines cytology, Morphogenesis drug effects, Tumor Necrosis Factor-alpha pharmacology
- Abstract
Background: The cytokines TNF (TNFSF2) and IFNγ are important mediators of inflammatory bowel diseases and contribute to enhanced intestinal epithelial permeability by stimulating apoptosis and/or disrupting tight junctions. Apoptosis and tight junctions are also important for epithelial tissue morphogenesis, but the effect of TNF and IFNγ on the process of intestinal epithelial morphogenesis is unknown., Methods/principal Findings: We have employed a three-dimensional cell culture system, reproducing in vivo-like multicellular organization of intestinal epithelial cells, to study the effect of TNF on intestinal epithelial morphogenesis and permeability. We show that human intestinal epithelial cells in three-dimensional culture assembled into luminal spheres consisting of a single layer of cells with structural, internal, and planar cell polarity. Exposure of preformed luminal spheres to TNF or IFNγ enhanced paracellular permeability, but via distinctive mechanisms. Thus, while both TNF and IFNγ, albeit in a distinguishable manner, induced the displacement of selected tight junction proteins, only TNF increased paracellular permeability via caspase-driven apoptosis and cell shedding. Infliximab and adalumimab inhibited these effects of TNF. Moreover, we demonstrate that TNF via its stimulatory effect on apoptosis fundamentally alters the process of intestinal epithelial morphogenesis, which contributes to the de novo generation of intestinal epithelial monolayers with increased permeability. Also IFNγ contributes to the de novo formation of monolayers with increased permeability, but in a manner that does not involve apoptosis., Conclusions: Our study provides an optimized 3D model system for the integrated analysis of (real-time) intestinal epithelial paracellular permeability and morphogenesis, and reveals apoptosis as a pivotal mechanism underlying the enhanced permeability and altered morphogenesis in response to TNF, but not IFNγ.
- Published
- 2011
- Full Text
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35. Thialkalivibrio nitratireducens sp. nov., a nitrate-reducing member of an autotrophic denitrifying consortium from a soda lake.
- Author
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Sorokin DY, Tourova TP, Sjollema KA, and Kuenen JG
- Subjects
- Chromatiaceae cytology, Chromatiaceae isolation & purification, Chromatiaceae metabolism, Egypt, Geologic Sediments microbiology, Hydrogen-Ion Concentration, Molecular Sequence Data, Oxidation-Reduction, Oxygen Consumption, Sulfates metabolism, Sulfur metabolism, Chromatiaceae classification, Nitrates metabolism, Phylogeny, Water Microbiology
- Abstract
Strain ALEN 2(T) was isolated from a mixed culture capable of complete autotrophic denitrification with thiosulfate as electron donor at pH 10; the mixed culture was enriched from sediment from Lake Fazda (Wadi Natrun, Egypt), a hypersaline alkaline lake. The isolate had large, non-motile, coccoid or barrel-shaped cells with intracellular sulfur globules. The bacterium was obligately chemolithoautotrophic. It grew with reduced sulfur compounds aerobically and anaerobically with nitrate as electron acceptor, nitrate being reduced to nitrite. It was moderately halophilic and obligately alkaliphilic. On the basis of genetic analysis and its unique phenotype, strain ALEN 2(T) (=DSM 14787(T)=UNIQEM 213(T)) is proposed as the type strain of a novel species of the genus Thialkalivibrio, Thialkalivibrio nitratireducens.
- Published
- 2003
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36. Thioalkalispira microaerophila gen. nov., sp. nov., a novel lithoautotrophic, sulfur-oxidizing bacterium from a soda lake.
- Author
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Sorokin DY, Tourova TP, Kolganova TV, Sjollema KA, and Kuenen JG
- Subjects
- Base Sequence, Cytochromes metabolism, DNA, Bacterial genetics, DNA, Ribosomal genetics, Fresh Water microbiology, Gammaproteobacteria genetics, Gammaproteobacteria isolation & purification, Gammaproteobacteria metabolism, Microscopy, Electron, Molecular Sequence Data, Oxidation-Reduction, Phenotype, Phylogeny, RNA, Bacterial genetics, RNA, Ribosomal, 16S genetics, Sulfur metabolism, Terminology as Topic, Gammaproteobacteria classification
- Abstract
An anaerobic enrichment medium (pH 10) with thiosulfate as electron donor and nitrate as electron acceptor was inoculated with sediment from soda lake Fazda (Wadi Natrun, Egypt); a novel strain, ALEN 1(T), was isolated from the subsequent enrichment culture. Cells of strain ALEN 1(T) had a spiral morphology (0.3-0.45 x 1-4 microm), were motile and had a single polar flagellum. Sphaeroplasts were formed by the cells and were rapidly lysed during prolonged aerobic incubation of cultures. Cells of strain ALEN 1(T) contained a membrane-associated yellow pigment. The metabolism of this novel organism was obligately chemolithoautotrophic, and thiosulfate or sulfide were utilized as electron donors. Washed cells of strain ALEN 1(T) oxidized thiosulfate, sulfide, polysulfide and elemental sulfur to sulfate. Best growth was observed when the strain was grown under micro-oxic conditions (1-2% O2 in gas phase), whereas growth was inhibited under fully oxic conditions. Nitrate was reduced to nitrite without growth of the novel organism, but other nitrogen oxides were not utilized as electron acceptors. Strain ALEN 1(T) was alkaliphilic and moderately halophilic. It grew between pH 8 and 10.4 (optimum around pH 10) with a salt concentration of between 0.3 and 1.5 M Na+ (optimum 0-5 M). The maximum growth rate (0.08 h(-1)) of the organism was achieved in a thiosulfate-limited micro-oxic continuous culture (pH 10). Phylogenetic analyses of the 16S rDNA sequences of strain ALEN 1(T) and its closest relatives demonstrated that this strain formed a deep branch within the gamma-Proteobacteria, with no obvious association to any described cluster of species/genera. On the basis of its unique physiological properties and distinct phylogenetic position, it is proposed that strain ALEN 1(T) (= DSM 14786(T) = UNICEM 212(T)) represents a novel genus within the gamma-Proteobacteria, for which the name Thioalkalispira is proposed. It is also proposed that the type species of this novel genus be named Thioalkalispira microaerophila.
- Published
- 2002
- Full Text
- View/download PDF
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