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Kraus L, Duchardt-Ferner E, Bräuchle E, Fürbacher S, Kelvin D, Marx H, Boussebayle A, Maurer LM, Bofill-Bosch C, Wöhnert J, Suess B. Development of a novel tobramycin dependent riboswitch. Nucleic Acids Res 2023; 51:11375-11385. [PMID: 37791877 PMCID: PMC10639043 DOI: 10.1093/nar/gkad767] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/30/2023] [Accepted: 09/12/2023] [Indexed: 10/05/2023] Open
Abstract
We herein report the selection and characterization of a new riboswitch dependent on the aminoglycoside tobramycin. Its dynamic range rivals even the tetracycline dependent riboswitch to be the current best performing, synthetic riboswitch that controls translation initiation. The riboswitch was selected with RNA Capture-SELEX, a method that not only selects for binding but also for structural changes in aptamers on binding. This study demonstrates how this method can fundamentally reduce the labour required for the de novo identification of synthetic riboswitches. The initially selected riboswitch candidate harbours two distinct tobramycin binding sites with KDs of 1.1 nM and 2.4 μM, respectively, and can distinguish between tobramycin and the closely related compounds kanamycin A and B. Using detailed genetic and biochemical analyses and 1H NMR spectroscopy, the proposed secondary structure of the riboswitch was verified and the tobramycin binding sites were characterized. The two binding sites were found to be essentially non-overlapping, allowing for a separate investigation of their contribution to the activity of the riboswitch. We thereby found that only the high-affinity binding site was responsible for regulatory activity, which allowed us to engineer a riboswitch from only this site with a minimal sequence size of 33 nt and outstanding performance.
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Affiliation(s)
- Leon Kraus
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
- Centre for Synthetic Biology, TU Darmstadt, 64287 Darmstadt, Germany
| | - Elke Duchardt-Ferner
- Institut für Molekulare Biowissenschaften und Zentrum für Biomolekulare Magnetische Resonanz (BMRZ), Goethe-Universität Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt, Germany
| | - Eric Bräuchle
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Simon Fürbacher
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Daniel Kelvin
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
- Centre for Synthetic Biology, TU Darmstadt, 64287 Darmstadt, Germany
| | - Hans Marx
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
- Institute of Microbiology and Microbial Biotechnology BOKU University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Adrien Boussebayle
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
- Interdisciplinary Nanoscience Center (iNANO), Gustav Wieds Vej 14, Aarhus University, DK-8000 Aarhus, Denmark
| | - Lisa-Marie Maurer
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
- Centre for Synthetic Biology, TU Darmstadt, 64287 Darmstadt, Germany
- Institut für Molekulare Biowissenschaften und Zentrum für Biomolekulare Magnetische Resonanz (BMRZ), Goethe-Universität Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt, Germany
| | - Cristina Bofill-Bosch
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Jens Wöhnert
- Institut für Molekulare Biowissenschaften und Zentrum für Biomolekulare Magnetische Resonanz (BMRZ), Goethe-Universität Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt, Germany
| | - Beatrix Suess
- Fachbereich Biologie, TU Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
- Centre for Synthetic Biology, TU Darmstadt, 64287 Darmstadt, Germany
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Dmytruk KV, Ruchala J, Fayura LR, Chrzanowski G, Dmytruk OV, Tsyrulnyk AO, Andreieva YA, Fedorovych DV, Motyka OI, Mattanovich D, Marx H, Sibirny AA. Efficient production of bacterial antibiotics aminoriboflavin and roseoflavin in eukaryotic microorganisms, yeasts. Microb Cell Fact 2023; 22:132. [PMID: 37474952 PMCID: PMC10357625 DOI: 10.1186/s12934-023-02129-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 06/21/2023] [Indexed: 07/22/2023] Open
Abstract
BACKGROUND Actinomycetes Streptomyces davaonensis and Streptomyces cinnabarinus synthesize a promising broad-spectrum antibiotic roseoflavin, with its synthesis starting from flavin mononucleotide and proceeding through an immediate precursor, aminoriboflavin, that also has antibiotic properties. Roseoflavin accumulation by the natural producers is rather low, whereas aminoriboflavin accumulation is negligible. Yeasts have many advantages as biotechnological producers relative to bacteria, however, no recombinant producers of bacterial antibiotics in yeasts are known. RESULTS Roseoflavin biosynthesis genes have been expressed in riboflavin- or FMN-overproducing yeast strains of Candida famata and Komagataella phaffii. Both these strains accumulated aminoriboflavin, whereas only the latter produced roseoflavin. Aminoriboflavin isolated from the culture liquid of C. famata strain inhibited the growth of Staphylococcus aureus (including MRSA) and Listeria monocytogenes. Maximal accumulation of aminoriboflavin in shake-flasks reached 1.5 mg L- 1 (C. famata), and that of roseoflavin was 5 mg L- 1 (K. phaffii). Accumulation of aminoriboflavin and roseoflavin by K. phaffii recombinant strain in a bioreactor reached 22 and 130 mg L- 1, respectively. For comparison, recombinant strains of the native bacterial producer S. davaonensis accumulated near one-order less of roseoflavin while no recombinant producers of aminoriboflavin was reported at all. CONCLUSIONS Yeast recombinant producers of bacterial antibiotics aminoriboflavin and roseoflavin were constructed and evaluated.
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Affiliation(s)
- Kostyantyn V Dmytruk
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine
| | - Justyna Ruchala
- University of Rzeszow, Zelwerowicza 4, Rzeszow, 35-601, Poland
| | - Liubov R Fayura
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine
| | | | - Olena V Dmytruk
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine
| | - Andriy O Tsyrulnyk
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine
| | - Yuliia A Andreieva
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine
| | - Daria V Fedorovych
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine
| | - Olena I Motyka
- Research Institute of Epidemiology and Hygiene of the Danylo Halytsky Lviv National Medical University, Zelena St, 12, Lviv, 79005, Ukraine
| | - Diethard Mattanovich
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, Vienna, Vienna, 1190, Austria
| | - Hans Marx
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, Vienna, Vienna, 1190, Austria
| | - Andriy A Sibirny
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov St, 14/16, Lviv, 79005, Ukraine.
- University of Rzeszow, Zelwerowicza 4, Rzeszow, 35-601, Poland.
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Russmayer H, Ergoth S, Marx H, Sauer M. Process engineering towards an oxidative cellular state improves 3-hydroxypropionic acid production with Lentilactobacillus diolivorans. Bioresour Technol 2023; 382:129160. [PMID: 37178779 DOI: 10.1016/j.biortech.2023.129160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 05/04/2023] [Accepted: 05/08/2023] [Indexed: 05/15/2023]
Abstract
3-hydroxypropionic acid (3-HP) is among the top platform chemicals proposed for bio based production by microbial fermentation from renewable resources. A promising renewable substrate for 3-HP production is crude glycerol. Only a few microorganisms can efficiently convert glycerol to 3-HP. Among the most promising organisms is Lentilactobacillus diolivorans. In this study, an already established fed-batch process, accumulating 28 g/L 3-HP, was used as a starting point for process engineering. The engineering approaches focused on modulating the cellular redox household towards a more oxidized state, as these conditions favour 3-HP production. Variations of oxygen and glucose availability (controlled by the glucose/glycerol ratio in the feed medium) individually already improved 3-HP production. However, the combination of both optimal parameters (30% O2, 0.025 mol/mol glu/gly) led to the production of 67.7 g/L 3-HP after 180 h of cultivation, which is so far the highest titer reported for 3-HP production using Lactobacillus spp.
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Affiliation(s)
- Hannes Russmayer
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria; University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, Muthgasse 18, 1190 Vienna, Austria
| | - Stefan Ergoth
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria; University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, Muthgasse 18, 1190 Vienna, Austria
| | - Hans Marx
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria; University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, Muthgasse 18, 1190 Vienna, Austria.
| | - Michael Sauer
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria; University of Natural Resources and Life Sciences, Vienna, Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, Muthgasse 18, 1190 Vienna, Austria
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Erian AM, Egermeier M, Marx H, Sauer M. Insights into the glycerol transport of Yarrowia lipolytica. Yeast 2022; 39:323-336. [PMID: 35348234 PMCID: PMC9311158 DOI: 10.1002/yea.3702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 02/18/2022] [Accepted: 03/07/2022] [Indexed: 12/02/2022] Open
Abstract
Cellular membranes separate cells from the environment and hence, from molecules essential for their survival. To overcome this hurdle, cells developed specialized transport proteins for the transfer of metabolites across these membranes. Crucial metabolites that need to cross the membrane of each living organism, are the carbon sources. While many organisms prefer glucose as a carbon source, the yeast Yarrowia lipolytica seems to favor glycerol over glucose. The fast growth of Y. lipolytica on glycerol and its flexible metabolism renders this yeast a fascinating organism to study the glycerol metabolism. Based on sequence similarities to the known fungal glycerol transporter ScStl1p and glycerol channel ScFps1p, ten proteins of Y. lipolytica were found that are potentially involved in glycerol uptake. To evaluate, which of these proteins is able to transport glycerol in vivo, a complementation assay with a glycerol transport‐deficient strain of Saccharomyces cerevisiae was performed. Six of the ten putative transporters enabled the growth of S. cerevisiae stl1Δ on glycerol and thus, were confirmed as glycerol transporting proteins. Disruption of the transporters in Y. lipolytica abolished its growth on 25 g/L glycerol, but the individual expression of five of the identified glycerol transporters restored growth. Surprisingly, the transporter‐disrupted Y. lipolytica strain retained its ability to grow on high glycerol concentrations. This study provides insight into the glycerol uptake of Y. lipolytica at low glycerol concentrations through the characterization of six glycerol transporters and indicates the existence of further mechanisms active at high glycerol concentrations. Six proteins of Yarrowia lipolytica were identified as glycerol transporters. Two channel proteins and four active transporters facilitated glycerol uptake. Identified transporters are involved in glycerol uptake <25 g/L glycerol. Indication of further glycerol transporters in Y. lipolytica was obtained.
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Affiliation(s)
- Anna M Erian
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Michael Egermeier
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Hans Marx
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Michael Sauer
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
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Vowinckel J, Hartl J, Marx H, Kerick M, Runggatscher K, Keller MA, Mülleder M, Day J, Weber M, Rinnerthaler M, Yu JSL, Aulakh SK, Lehmann A, Mattanovich D, Timmermann B, Zhang N, Dunn CD, MacRae JI, Breitenbach M, Ralser M. The metabolic growth limitations of petite cells lacking the mitochondrial genome. Nat Metab 2021; 3:1521-1535. [PMID: 34799698 PMCID: PMC7612105 DOI: 10.1038/s42255-021-00477-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 09/10/2021] [Indexed: 12/25/2022]
Abstract
Eukaryotic cells can survive the loss of their mitochondrial genome, but consequently suffer from severe growth defects. 'Petite yeasts', characterized by mitochondrial genome loss, are instrumental for studying mitochondrial function and physiology. However, the molecular cause of their reduced growth rate remains an open question. Here we show that petite cells suffer from an insufficient capacity to synthesize glutamate, glutamine, leucine and arginine, negatively impacting their growth. Using a combination of molecular genetics and omics approaches, we demonstrate the evolution of fast growth overcomes these amino acid deficiencies, by alleviating a perturbation in mitochondrial iron metabolism and by restoring a defect in the mitochondrial tricarboxylic acid cycle, caused by aconitase inhibition. Our results hence explain the slow growth of mitochondrial genome-deficient cells with a partial auxotrophy in four amino acids that results from distorted iron metabolism and an inhibited tricarboxylic acid cycle.
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Affiliation(s)
- Jakob Vowinckel
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK
- Biognosys AG, Schlieren, Switzerland
| | - Johannes Hartl
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Biochemistry, Berlin, Germany
| | - Hans Marx
- Department of Biotechnology, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
| | - Martin Kerick
- Sequencing Core Facility, Max Planck Institute for Molecular Genetics and Max Planck Unit for the Science of Pathogens, Berlin, Germany
- Institute of Parasitology and Biomedicine 'López-Neyra' (IPBLN, CSIC), Granada, Spain
| | - Kathrin Runggatscher
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK
| | - Markus A Keller
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK
- Institute of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael Mülleder
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Biochemistry, Berlin, Germany
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Jason Day
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
| | - Manuela Weber
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Mark Rinnerthaler
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Jason S L Yu
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Simran Kaur Aulakh
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Andrea Lehmann
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Biochemistry, Berlin, Germany
| | - Diethard Mattanovich
- Department of Biotechnology, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
| | - Bernd Timmermann
- Sequencing Core Facility, Max Planck Institute for Molecular Genetics and Max Planck Unit for the Science of Pathogens, Berlin, Germany
| | - Nianshu Zhang
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK
| | - Cory D Dunn
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
- Department of Molecular Biology and Genetics, Koç University, İstanbul, Turkey
| | - James I MacRae
- Metabolomics Laboratory, The Francis Crick Institute, London, UK
| | | | - Markus Ralser
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, UK.
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Biochemistry, Berlin, Germany.
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, UK.
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Li J, Rinnerthaler M, Hartl J, Weber M, Karl T, Breitenbach-Koller H, Mülleder M, Vowinckel J, Marx H, Sauer M, Mattanovich D, Ata Ö, De S, Greslehner GP, Geltinger F, Burhans B, Grant C, Doronina V, Ralser M, Streubel MK, Grabner C, Jarolim S, Moßhammer C, Gourlay CW, Hasek J, Cullen PJ, Liti G, Ralser M, Breitenbach M. Slow Growth and Increased Spontaneous Mutation Frequency in Respiratory Deficient afo1- Yeast Suppressed by a Dominant Mutation in ATP3. G3 (Bethesda) 2020; 10:4637-4648. [PMID: 33093184 PMCID: PMC7718765 DOI: 10.1534/g3.120.401537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/19/2020] [Indexed: 12/26/2022]
Abstract
A yeast deletion mutation in the nuclear-encoded gene, AFO1, which codes for a mitochondrial ribosomal protein, led to slow growth on glucose, the inability to grow on glycerol or ethanol, and loss of mitochondrial DNA and respiration. We noticed that afo1- yeast readily obtains secondary mutations that suppress aspects of this phenotype, including its growth defect. We characterized and identified a dominant missense suppressor mutation in the ATP3 gene. Comparing isogenic slowly growing rho-zero and rapidly growing suppressed afo1- strains under carefully controlled fermentation conditions showed that energy charge was not significantly different between strains and was not causal for the observed growth properties. Surprisingly, in a wild-type background, the dominant suppressor allele of ATP3 still allowed respiratory growth but increased the petite frequency. Similarly, a slow-growing respiratory deficient afo1- strain displayed an about twofold increase in spontaneous frequency of point mutations (comparable to the rho-zero strain) while the suppressed strain showed mutation frequency comparable to the respiratory-competent WT strain. We conclude, that phenotypes that result from afo1- are mostly explained by rapidly emerging mutations that compensate for the slow growth that typically follows respiratory deficiency.
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Affiliation(s)
- Jing Li
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
- Universite Cote d'Azur, CNRS, Inserm, IRCAN, Nice, France
| | | | - Johannes Hartl
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Department of Biochemistry, Charité University Medicine, Berlin Germany
| | - Manuela Weber
- Department of Biosciences, University of Salzburg, Austria
| | - Thomas Karl
- Department of Biosciences, University of Salzburg, Austria
| | | | - Michael Mülleder
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Department of Biochemistry, Charité University Medicine, Berlin Germany
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, 1Midland Rd, London NW1 1AT, UK
| | - Jakob Vowinckel
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Biognosys AG, Wagistrasse 21, 8952 Schlieren, Switzerland
| | - Hans Marx
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Michael Sauer
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Diethard Mattanovich
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Muthgasse 11, A-1190 Vienna, Austria
| | - Özge Ata
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Muthgasse 11, A-1190 Vienna, Austria
| | - Sonakshi De
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Muthgasse 11, A-1190 Vienna, Austria
| | | | | | - Bill Burhans
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, New York
| | - Chris Grant
- Faculty of Biology, Medicine, and Health, University of Manchester, Manchester M13 9PT, UK
| | | | - Meryem Ralser
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, 1Midland Rd, London NW1 1AT, UK
| | | | | | | | | | - Campbell W Gourlay
- Department of Biosciences, University of Kent, Canterbury Kent CT2 7NJ, United Kingdom
| | - Jiri Hasek
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, Prague 4 142 20, Czech Republic
| | - Paul J Cullen
- Department of Biological Sciences, University at Buffalo, NY 14260
| | - Gianni Liti
- Institute for Research on Cancer and Ageing of Nice (IRCAN), CNRS, INSERM, Université Côte d'Azur, 06107 NICE, France
| | - Markus Ralser
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Rd, Cambridge CB2 1GA, UK
- Department of Biochemistry, Charité University Medicine, Berlin Germany
- The Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, 1Midland Rd, London NW1 1AT, UK
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Erian AM, Egermeier M, Rassinger A, Marx H, Sauer M. Identification of the citrate exporter Cex1 of Yarrowia lipolytica. FEMS Yeast Res 2020; 20:5912837. [DOI: 10.1093/femsyr/foaa055] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 09/25/2020] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Yarrowia lipolytica is a yeast with many talents, one of them being the production of citric acid. Although the citrate biosynthesis is well studied, little is known about the transport mechanism by which citrate is exported. To gain better insight into this mechanism, we set out to identify a transporter involved in citrate export of Y. lipolytica. A total of five proteins were selected for analysis based on their similarity to a known citrate exporter, but neither a citrate transport activity nor any other phenotypic function could be attributed to them. Differential gene expression analysis of two strains with a distinct citrate productivity revealed another three putative transporters, one of which is YALI0D20196p. Disrupting YALI0D20196g in Y. lipolytica abolished citrate production, while extrachromosomal expression enhanced citrate production 5.2-fold in a low producing wildtype. Furthermore, heterologous expression of YALI0D20196p in the non-citrate secreting yeast Saccharomyces cerevisiae facilitated citrate export. Likewise, expression of YALI0D20196p complemented the ability to secrete citrate in an export-deficient strain of Aspergillus niger, confirming a citrate export function of YALI0D20196p. This report on the identification of the first citrate exporter in Y. lipolytica, termed Cex1, represents a valuable starting point for further investigations of the complex transport processes in yeasts.
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Affiliation(s)
- Anna Maria Erian
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU-University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Michael Egermeier
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU-University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Alice Rassinger
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU-University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Hans Marx
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU-University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Michael Sauer
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
- Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU-University of Natural Resources and Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
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Egermeier M, Sauer M, Marx H. Golden Gate-based metabolic engineering strategy for wild-type strains of Yarrowia lipolytica. FEMS Microbiol Lett 2019; 366:5304171. [PMID: 30698703 DOI: 10.1093/femsle/fnz022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 01/27/2019] [Indexed: 12/14/2022] Open
Abstract
The yeast Yarrowia lipolytica represents a future microbial cell factory for numerous applications in a bio-based economy. Outstanding feature of this yeast is the metabolic flexibility in utilising various substrates (sugars, fatty acids, glycerol, etc.). The potential of wild-type isolates of Y. lipolytica to convert glycerol into various value-added compounds is attracting attention of academia and industry. However, the already established tools for efficient engineering of the metabolism of Y. lipolytica are often dependent on genetic features like auxotrophic markers. With the present work we want to introduce a new set of vectors for metabolic engineering strategies, including CRISPR/Cas9 technology. The system is based on GoldenMOCS, a recently established rapid Golden Gate cloning strategy applicable in multiple organisms. We could show that our new GoldenMOCS plasmids are suitable for the extrachromosomal overexpression of the gene glycerol kinase (GUT1) in wild-type isolates of Y. lipolytica resulting in enhanced conversion of glycerol to erythritol and citric acid. Moreover, a GoldenMOCS plasmid for CRISPR/Cas9 mediated genome editing has been designed, which facilitates single gene knock-outs with efficiencies between 6% and 25% in strains with genetic wild-type background.
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Affiliation(s)
- Michael Egermeier
- CD-Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria.,Department of Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Michael Sauer
- CD-Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria.,Department of Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.,Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Hans Marx
- CD-Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria.,Department of Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
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Russmayer H, Marx H, Sauer M. Microbial 2-butanol production with Lactobacillus diolivorans. Biotechnol Biofuels 2019; 12:262. [PMID: 31709011 PMCID: PMC6833138 DOI: 10.1186/s13068-019-1594-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/16/2019] [Indexed: 05/14/2023]
Abstract
BACKGROUND Biobutanol has great potential as biofuel of the future. However, only a few organisms have the natural ability to produce butanol. Amongst them, Clostridium spp. are the most efficient producers. The high toxicity of biobutanol constitutes one of the bottlenecks within the biobutanol production process which often suffers from low final butanol concentrations and yields. Butanol tolerance is a key driver for process optimisation and, therefore, in the search for alternative butanol production hosts. Many Lactobacillus species show a remarkable tolerance to solvents and some Lactobacillus spp. are known to naturally produce 2-butanol from meso-2,3-butanediol (meso-2,3-BTD) during anaerobic sugar fermentations. Lactobacillus diolivorans showed already to be highly efficient in the production of other bulk chemicals using a simple two-step metabolic pathway. Exactly, the same pathway enables this cell factory for 2-butanol production. RESULTS Due to the inability of L. diolivorans to produce meso-2,3-BTD, a two-step cultivation processes with Serratia marcescens has been developed. S. marcescens is a very efficient producer of meso-2,3-BTD from glucose. The process yielded a butanol concentration of 10 g/L relying on wild-type bacterial strains. A further improvement of the maximum butanol titer was achieved using an engineered L. diolivorans strain overexpressing the endogenous alcohol dehydrogenase pduQ. The two-step cultivation process based on the engineered strain led to a maximum 2-butanol titer of 13.4 g/L, which is an increase of 34%. CONCLUSION In this study, L. diolivorans is for the first time described as a good natural producer for 2-butanol from meso-2,3-butanediol. Through the application of a two-step cultivation process with S. marcescens, 2-butanol can be produced from glucose in a one-vessel, two-step microbial process.
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Affiliation(s)
- Hannes Russmayer
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Hans Marx
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Michael Sauer
- CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, 1190 Vienna, Austria
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
- ACIB GmbH, Muthgasse 11, 1190 Vienna, Austria
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Prielhofer R, Barrero JJ, Steuer S, Gassler T, Zahrl R, Baumann K, Sauer M, Mattanovich D, Gasser B, Marx H. GoldenPiCS: a Golden Gate-derived modular cloning system for applied synthetic biology in the yeast Pichia pastoris. BMC Syst Biol 2017; 11:123. [PMID: 29221460 PMCID: PMC5723102 DOI: 10.1186/s12918-017-0492-3] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 11/13/2017] [Indexed: 01/05/2023]
Abstract
BACKGROUND State-of-the-art strain engineering techniques for the host Pichia pastoris (syn. Komagataella spp.) include overexpression of homologous and heterologous genes, and deletion of host genes. For metabolic and cell engineering purposes the simultaneous overexpression of more than one gene would often be required. Very recently, Golden Gate based libraries were adapted to optimize single expression cassettes for recombinant proteins in P. pastoris. However, an efficient toolbox allowing the overexpression of multiple genes at once was not available for P. pastoris. METHODS With the GoldenPiCS system, we provide a flexible modular system for advanced strain engineering in P. pastoris based on Golden Gate cloning. For this purpose, we established a wide variety of standardized genetic parts (20 promoters of different strength, 10 transcription terminators, 4 genome integration loci, 4 resistance marker cassettes). RESULTS All genetic parts were characterized based on their expression strength measured by eGFP as reporter in up to four production-relevant conditions. The promoters, which are either constitutive or regulatable, cover a broad range of expression strengths in their active conditions (2-192% of the glyceraldehyde-3-phosphate dehydrogenase promoter P GAP ), while all transcription terminators and genome integration loci led to equally high expression strength. These modular genetic parts can be readily combined in versatile order, as exemplified for the simultaneous expression of Cas9 and one or more guide-RNA expression units. Importantly, for constructing multigene constructs (vectors with more than two expression units) it is not only essential to balance the expression of the individual genes, but also to avoid repetitive homologous sequences which were otherwise shown to trigger "loop-out" of vector DNA from the P. pastoris genome. CONCLUSIONS GoldenPiCS, a modular Golden Gate-derived P. pastoris cloning system, is very flexible and efficient and can be used for strain engineering of P. pastoris to accomplish pathway expression, protein production or other applications where the integration of various DNA products is required. It allows for the assembly of up to eight expression units on one plasmid with the ability to use different characterized promoters and terminators for each expression unit. GoldenPiCS vectors are available at Addgene.
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Affiliation(s)
- Roland Prielhofer
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Juan J Barrero
- Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria.,Present Address: Department of Chemical, Biological, and Environmental Engineering, Escola d'Enginyeria, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Stefanie Steuer
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Present Address: Novartis, Vienna, Austria
| | - Thomas Gassler
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Richard Zahrl
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Kristin Baumann
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Michael Sauer
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Diethard Mattanovich
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria
| | - Brigitte Gasser
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria. .,Austrian Centre of Industrial Biotechnology (acib), Vienna, Austria.
| | - Hans Marx
- Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria
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Lindlbauer KA, Marx H, Sauer M. 3-Hydroxypropionaldehyde production from crude glycerol by Lactobacillus diolivorans with enhanced glycerol uptake. Biotechnol Biofuels 2017; 10:295. [PMID: 29225699 PMCID: PMC5719546 DOI: 10.1186/s13068-017-0982-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/26/2017] [Indexed: 05/27/2023]
Abstract
BACKGROUND In their quest for sustainable development and effective management of greenhouse gas emissions, our societies pursue a shift away from fossil-based resources towards renewable resources. With 95% of our current transportation energy being petroleum based, the application of alternative, carbon-neutral products-among them biodiesel-is inevitable. In order to enhance the cost structure of biodiesel biorefineries, the valorization of the crude glycerol waste stream into high-value platform chemicals is of major importance. RESULTS The purpose of this study is the production of 3-hydroxypropionaldehyde (3-HPA) from biodiesel-derived crude glycerol by Lactobacillus diolivorans. Particular focus is given on overcoming potential limitations of glycerol transport into the cell, in order to use the cells' total glycerol dehydratase capability towards the formation of 3-HPA as the main product. Recombinant overexpression of the endogenous glycerol uptake facilitating protein PduF results in a significant increase of glycerol conversion by a factor of 1.3. Concomitantly, glycerol dehydratase activity increased from initially 1.70 ± 0.03 U/mg protein to 2.23 ± 0.11 U/mg protein. With this approach, an average productivity of 4.8 g3-HPA/(gCDM h) yielding up to 35.9 g/L 3-HPA and 0.91 mol3-HPA/molGlycerol have been obtained. CONCLUSION Lactobacillus diolivorans proves to be a valuable cell factory for the utilization of crude glycerol delivering high-value C3 chemicals like 3-HPA, 1,3-propanediol (1,3-PDO) and 3-hydroxypropionic acid (3-HP). Enhancing the glycerol influx into the cell by genetic engineering was successful paving the way towards the commercial production of 3-HPA.
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Affiliation(s)
- Katharina Anna Lindlbauer
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Hans Marx
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Michael Sauer
- CD-Laboratory for Biotechnology of Glycerol, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
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Sarkari P, Marx H, Blumhoff ML, Mattanovich D, Sauer M, Steiger MG. An efficient tool for metabolic pathway construction and gene integration for Aspergillus niger. Bioresour Technol 2017; 245:1327-1333. [PMID: 28533066 DOI: 10.1016/j.biortech.2017.05.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 04/28/2017] [Accepted: 05/01/2017] [Indexed: 06/07/2023]
Abstract
Metabolic engineering requires functional genetic tools for easy and quick generation of multiple pathway variants. A genetic engineering toolbox for A. niger is presented, which facilitates the generation of strains carrying heterologous expression cassettes at a defined genetic locus. The system is compatible with Golden Gate cloning, which facilitates the DNA construction process and provides high design flexibility. The integration process is mediated by a CRISPR/Cas9 strategy involving the cutting of both the genetic integration locus (pyrG) as well as the integrating plasmid. Only a transient expression of Cas9 is necessary and the carrying plasmid is readily lost using a size-reduced AMA1 variant. A high integration efficiency into the fungal genome of up to 100% can be achieved, thus reducing the screening process significantly. The feasibility of the approach was demonstrated by the integration of an expression cassette enabling the production of aconitic acid in A. niger.
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Affiliation(s)
- Parveen Sarkari
- ACIB GmbH, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Hans Marx
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Marzena L Blumhoff
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria; School of Bioengineering, University of Applied Sciences FH-Campus Wien, Vienna, Austria
| | - Diethard Mattanovich
- ACIB GmbH, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Michael Sauer
- ACIB GmbH, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria.
| | - Matthias G Steiger
- ACIB GmbH, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
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Abstract
The yeast Yarrowia lipolytica is a fascinating microorganism with an amazing metabolic flexibility. This yeast grows very well on a wide variety of carbon sources from alkanes over lipids, to sugars and glycerol. Y. lipolytica accumulates a wide array of industrially relevant metabolites. It is very tolerant to many environmental factors, above all the pH value. It grows perfectly well over a wide pH range, but it has been described, that the pH has a decisive influence on the metabolite pattern accumulated by this yeast. Here, we set out to characterize the metabolism of different Y. lipolytica strains, isolated from various environments, growing on glycerol at different pH values. The conditions applied for strain characterization are of utmost importance. Shake flask cultures lead to very different results, when compared to controlled conditions in bioreactors regarding pH and aeration. Only one of the tested strains was able to accumulate high amounts of citric acid in shake flask experiments, whereas a group of six strains turned out to accumulate citric acid efficiently under controlled conditions. The present study shows that strains isolated from dairy products predominantly accumulate sugar alcohols at any given pH, when grown on glycerol under nitrogen-limitation.
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Affiliation(s)
- Michael Egermeier
- Christian Doppler-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
- Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
| | - Hannes Russmayer
- Christian Doppler-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
- Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
| | - Michael Sauer
- Christian Doppler-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
- Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
- ACIB GmbH, Austrian Centre of Industrial BiotechnologyVienna, Austria
| | - Hans Marx
- Christian Doppler-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
- Department of Biotechnology, BOKU-Vienna Institute of Bio Technology (VIBT), University of Natural Resources and Life SciencesVienna, Austria
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Diethard M, Gasser B, Egermeier M, Marx H, Sauer M. Industrial Microorganisms: Saccharomyces cerevisiaeand other Yeasts. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807796.ch18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Mattanovich Diethard
- BOKU - University of Natural Resources and Life Sciences; Department of Biotechnology; Muthgasse 18 1190 Vienna Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH); Muthgasse 18 1190 Vienna Austria
| | - Brigitte Gasser
- BOKU - University of Natural Resources and Life Sciences; Department of Biotechnology; Muthgasse 18 1190 Vienna Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH); Muthgasse 18 1190 Vienna Austria
| | - Michael Egermeier
- BOKU - University of Natural Resources and Life Sciences; Department of Biotechnology; Muthgasse 18 1190 Vienna Austria
- BOKU - University of Natural Resources and Life Sciences; CD-Laboratory for Biotechnology of Glycerol; Muthgasse 18 1190 Vienna Austria
| | - Hans Marx
- BOKU - University of Natural Resources and Life Sciences; Department of Biotechnology; Muthgasse 18 1190 Vienna Austria
| | - Michael Sauer
- BOKU - University of Natural Resources and Life Sciences; Department of Biotechnology; Muthgasse 18 1190 Vienna Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH); Muthgasse 18 1190 Vienna Austria
- BOKU - University of Natural Resources and Life Sciences; CD-Laboratory for Biotechnology of Glycerol; Muthgasse 18 1190 Vienna Austria
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Lindlbauer KA, Marx H, Sauer M. Effect of carbon pulsing on the redox household of Lactobacillus diolivorans in order to enhance 1,3-propanediol production. N Biotechnol 2016; 34:32-39. [PMID: 27769866 DOI: 10.1016/j.nbt.2016.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/06/2016] [Accepted: 10/07/2016] [Indexed: 11/28/2022]
Abstract
This study investigates potential limitations of 1,3-propanediol formation by Lactobacillus diolivorans. Particular focus is given to enhanced glycerol utilization as well as the elimination of by-product formation. The key aspect is a modulation of the redox household by process engineering through the application of carbon pulses. A shift in the product pattern of C3 products was achieved, improving the ratio of 1,3-propanediol versus 3-hydroxypropionic acid up to a level of 20:1. Moreover, in combination with alternative feeding strategies this ratio was enhanced up to 45:1 and the maximum observed productivity of 1,3-propanediol could be significantly increased to 1.7g/Lh.
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Affiliation(s)
- Katharina Anna Lindlbauer
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Hans Marx
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria.
| | - Michael Sauer
- CD-Laboratory for Biotechnology of Glycerol, Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Vienna, Austria; Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
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Bellasio M, Peymann A, Steiger MG, Valli M, Sipiczki M, Sauer M, Graf AB, Marx H, Mattanovich D. Complete genome sequence and transcriptome regulation of the pentose utilizing yeastSugiyamaella lignohabitans. FEMS Yeast Res 2016; 16:fow037. [DOI: 10.1093/femsyr/fow037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2016] [Indexed: 01/17/2023] Open
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Neubauer S, Chu DB, Marx H, Sauer M, Hann S, Koellensperger G. LC-MS/MS-based analysis of coenzyme A and short-chain acyl-coenzyme A thioesters. Anal Bioanal Chem 2015; 407:6681-8. [PMID: 26168961 DOI: 10.1007/s00216-015-8825-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/03/2015] [Accepted: 06/03/2015] [Indexed: 11/27/2022]
Abstract
Absolute quantification of intracellular coenzyme A (CoA), coenzyme A disulfide, and short-chain acyl-coenzyme A thioesters was addressed by developing a tailored metabolite profiling method based on liquid chromatography in combination with tandem mass spectrometric detection (LC-MS/MS). A reversed phase chromatographic separation was established which is capable of separating a broad spectrum of CoA, its corresponding derivatives, and their isomers despite the fact that no ion-pairing reagent was used (which was considered as a key advantage of the method). Excellent analytical figures of merit such as high sensitivity (LODs in the nM to sub-nM range) and high repeatability (routinely 4 %; N = 15) were obtained. Method validation comprised a study on standard purity, stability, and recoveries during sample preparation. Uniformly labeled U(13)C yeast cell extracts offered ideal internal standards for validation purposes and for a quantification exercise in the rumen bacterium Megasphaera elsdenii.
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Affiliation(s)
- Stefan Neubauer
- Department of Chemistry, Division of Analytical Chemistry, University of Natural Resources and Life Sciences-BOKU, 1190, Vienna, Austria
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Pflügl S, Marx H, Mattanovich D, Sauer M. Heading for an economic industrial upgrading of crude glycerol from biodiesel production to 1,3-propanediol by Lactobacillus diolivorans. Bioresour Technol 2013; 152:499-504. [PMID: 24333679 DOI: 10.1016/j.biortech.2013.11.041] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 11/11/2013] [Accepted: 11/14/2013] [Indexed: 06/03/2023]
Abstract
Lactobacillus diolivorans was evaluated as a potential organism for production of 1,3-propanediol under industrially relevant conditions. Crude glycerol of different origins has been tested and showed no inhibitory effects on growth or production. Using crude glycerol from biodiesel production from palm oil 85 g/l 1,3-propanediol have been obtained with a productivity of 0.45 g/lh in a fed-batch cultivation. Sugar necessary for the formation of biomass was replaced with a hydrolysate from lignocellulosic material resulting in 75 g/l 1,3-propanediol and a productivity of 0.36 g/lh. Lignocellulosic hydrolysate contained the potential inhibitors furfural and 5-hydroxymethylfurfural at concentrations of 0.7 and 0.3 g/l, respectively. Addition of furfural and 5-hydroxymethylfurfural to batch cultures in said concentrations did not show inhibitory effects on growth or 1,3-propanediol production.
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Affiliation(s)
- Stefan Pflügl
- School of Bioengineering, FH Campus Wien - University of Applied Sciences, Muthgasse 62, 1190 Vienna, Austria; Department of Biotechnology, BOKU - VIBT University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Hans Marx
- Department of Biotechnology, BOKU - VIBT University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria.
| | - Diethard Mattanovich
- Department of Biotechnology, BOKU - VIBT University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria; Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Michael Sauer
- Department of Biotechnology, BOKU - VIBT University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria; Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 11, 1190 Vienna, Austria
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Pflügl S, Marx H, Mattanovich D, Sauer M. Genetic engineering ofLactobacillus diolivorans. FEMS Microbiol Lett 2013; 344:152-8. [DOI: 10.1111/1574-6968.12168] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 04/22/2013] [Accepted: 04/27/2013] [Indexed: 11/30/2022] Open
Affiliation(s)
| | - Hans Marx
- Department of Biotechnology; BOKU - VIBT University of Natural Resources and Life Sciences; Vienna; Austria
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Gasser B, Prielhofer R, Marx H, Maurer M, Nocon J, Steiger M, Puxbaum V, Sauer M, Mattanovich D. Pichia pastoris: protein production host and model organism for biomedical research. Future Microbiol 2013; 8:191-208. [DOI: 10.2217/fmb.12.133] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Pichia pastoris is the most frequently used yeast system for heterologous protein production today. The last few years have seen several products based on this platform reach approval as biopharmaceutical drugs. Successful glycoengineering to humanize N-glycans is further fuelling this development. However, detailed understanding of the yeast’s physiology, genetics and regulation has only developed rapidly in the last few years since published genome sequences have become available. An expanding toolbox of genetic elements and strains for the improvement of protein production is being generated, including promoters, gene copy-number enhancement, gene knockout and high-throughput methods. Protein folding and secretion have been identified as significant bottlenecks in yeast expression systems, pinpointing a major target for strain optimization. At the same time, it has become obvious that P. pastoris, as an evolutionarily more ‘ancient’ yeast, may in some cases be a better model for human cell biology and disease than Saccharomyces cerevisiae.
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Affiliation(s)
- Brigitte Gasser
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), 1190 Vienna, Austria
| | - Roland Prielhofer
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
| | - Hans Marx
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
| | - Michael Maurer
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), 1190 Vienna, Austria
- University of Applied Sciences FH-Campus Vienna, School of Bioengineering, 1190 Vienna, Austria
| | - Justyna Nocon
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
| | - Matthias Steiger
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), 1190 Vienna, Austria
| | - Verena Puxbaum
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), 1190 Vienna, Austria
| | - Michael Sauer
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), 1190 Vienna, Austria
| | - Diethard Mattanovich
- University of Natural Resources & Life Sciences (BOKU), Department of Biotechnology, 1190 Vienna, Austria
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Abstract
The rumen is one of the most complicated and most fascinating microbial ecosystems in nature. A wide variety of microbial species, including bacteria, fungi and protozoa act together to bioconvert (ligno)cellulosic plant material into compounds, which can be taken up and metabolized by the ruminant. Thus, the rumen perfectly resembles a solution to a current industrial problem: the biorefinery, which aims at the bioconversion of lignocellulosic material into fuels and chemicals. We suggest to intensify the studies of the ruminal microbial ecosystem from an industrial microbiologists point of view in order to make use of this rich source of organisms and enzymes.
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Affiliation(s)
- Michael Sauer
- Department of Biotechnology, BOKU-VIBT University of Natural Resources and Life Sciences, Muthgasse 18, Vienna 1190, Austria.
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Pflügl S, Marx H, Mattanovich D, Sauer M. 1,3-Propanediol production from glycerol with Lactobacillus diolivorans. Bioresour Technol 2012; 119:133-140. [PMID: 22728193 DOI: 10.1016/j.biortech.2012.05.121] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 05/22/2012] [Accepted: 05/23/2012] [Indexed: 05/27/2023]
Abstract
The aim of this study was to evaluate the natural producer Lactobacillus diolivorans as potential production organism of 1,3-propanediol from glycerol. Different cultivation parameters, such as oxygen supply, feeding-strategy, or medium composition have been tested in batch and fed-batch cultivations. The 1,3-propanediol concentration obtained in batch cultivations was 41.7 g/l. This could be increased to 73.7 g/l in a fed-batch co-feeding glucose and glycerol with a molar ratio of 0.1. Yeast extract as part of the MRS cultivation medium could be replaced by nicotinic acid and riboflavin. Furthermore, the addition of Vitamin B(12) to the culture medium increased production by 15% to a final titer of 84.5 g/l 1,3-propanediol.
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Affiliation(s)
- Stefan Pflügl
- School of Bioengineering, FH Campus Wien - University of Applied Sciences, Muthgasse 62, 1190 Vienna, Austria
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Blumhoff M, Steiger MG, Marx H, Mattanovich D, Sauer M. Six novel constitutive promoters for metabolic engineering of Aspergillus niger. Appl Microbiol Biotechnol 2012; 97:259-67. [DOI: 10.1007/s00253-012-4207-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 05/22/2012] [Accepted: 05/30/2012] [Indexed: 11/29/2022]
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Blatzonis K, Fernández-Sanchez J, Marx H. Real-time Elastosonographie der Weichteilpathologie - Aktueller Stand und Möglichkeiten. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Bloomston M, Marsh C, Walker J, Coyle W, Marx H, Tahiri S, Moran Cruz C, Aguilar LK, Aguilar-Cordova E, Chung VM. Phase I trial of gene-mediated cytotoxic immunotherapy in combination with chemoradiation for locally advanced pancreatic cancer. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.4_suppl.195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
195 Background: More than 80% of patients with pancreatic cancer present with locally advanced or metastatic disease and have a median survival of only 6 months. Immunotherapy approaches may improve outcomes. Gene Mediated Cytotoxic Immunotherapy (GMCI) is an approach that generates a systemic anti-tumor vaccine effect through intra-tumoral delivery of an adenoviral vector expressing the HSV-thymidine kinase gene (AdV-tk) followed by anti-herpetic prodrug and synergy with chemoradiation. The mechanisms of action involve tumor cytotoxicity, activation of antigen presenting cells and stimulation of systemic anti-tumor T-cell immunity. Safety with potential efficacy has been demonstrated in multiple clinical studies. This is the first application of GMCI in pancreatic cancer. Methods: This study evaluated 4 dose levels of AdV-tk (3x1010 to 1x1012 vector particles) injected into locally advanced tumors via EUS or CT-guidance before and during week 3 of standard 5-FU-chemoradiation. Valacyclovir (Valtrex, GSK) prodrug was given for 14 days after each of 2 AdV-tk injections. Results: The study completed accrual with 13 patients enrolled and 12 completing therapy with 3 at each of the 4 dose levels. One patient refused further participation during course 1 after recovering from azotemia. Median age was 64 years (range 55-81) and median baseline CA19-9 was 1634 U/ml. No dose limiting toxicities and no injection related complications occurred. Possibly related grade 3-4 toxicities, all of which were transient, included dehydration, azotemia and worsening elevation of bilirubin and AST. Kaplan-Meier estimated median survival is 12.2 months with 6 patients still alive at 8-20 months. Two patients achieved a partial response by RECIST criteria. One occurred in week 6 despite discontinuing 5-FU/radiation during week 1. The other had gradual decrease of a 7 cm tumor over 11 months. Serum CA19-9 levels decreased in 8/8 evaluable patients by 32-91% at 3 months after treatment initiation. Conclusions: AdV-tk can be safely injected into pancreatic tumors and combined with standard chemoradiation. Early results are highly encouraging and justify further evaluation in a phase II study. [Table: see text]
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Affiliation(s)
- M. Bloomston
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - C. Marsh
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - J. Walker
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - W. Coyle
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - H. Marx
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - S. Tahiri
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - C. Moran Cruz
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - L. K. Aguilar
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - E. Aguilar-Cordova
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
| | - V. M. Chung
- The Ohio State University Medical Center, Columbus, OH; Scripps Green Hospital, La Jolla, CA; City of Hope National Medical Center, Duarte, CA; The Ohio State University, Columbus, OH; Advantagene, Inc., Auburndale, MA; City of Hope, Duarte, CA
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Marx H, Mecklenbräuker A, Gasser B, Sauer M, Mattanovich D. Directed gene copy number amplification inPichia pastorisby vector integration into the ribosomal DNA locus. FEMS Yeast Res 2009; 9:1260-70. [DOI: 10.1111/j.1567-1364.2009.00561.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Resina D, Maurer M, Cos O, Arnau C, Carnicer M, Marx H, Gasser B, Valero F, Mattanovich D, Ferrer P. Engineering of bottlenecks in Rhizopus oryzae lipase production in Pichia pastoris using the nitrogen source-regulated FLD1 promoter. N Biotechnol 2009; 25:396-403. [DOI: 10.1016/j.nbt.2009.01.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Revised: 01/23/2009] [Accepted: 01/29/2009] [Indexed: 10/21/2022]
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Marx H. Untersuchungen zur Innervation des Kehlkopfes. Acta Otolaryngol 2009. [DOI: 10.3109/00016482809121010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Marx H, Mattanovich D, Sauer M. Overexpression of the riboflavin biosynthetic pathway in Pichia pastoris. Microb Cell Fact 2008; 7:23. [PMID: 18664246 PMCID: PMC2517057 DOI: 10.1186/1475-2859-7-23] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Accepted: 07/29/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND High cell density cultures of Pichia pastoris grown on methanol tend to develop yellow colored supernatants, attributed to the release of free flavins. The potential of P. pastoris for flavin overproduction is therefore given, but not pronounced when the yeast is grown on glucose. The aim of this study is to characterize the relative regulatory impact of each riboflavin synthesis gene. Deeper insight into pathway control and the potential of deregulation is established by overexpression of the single genes as well as a combined deregulation of up to all six riboflavin synthesis genes. RESULTS Overexpression of the first gene of the riboflavin biosynthetic pathway (RIB1) is already sufficient to obtain yellow colonies and the accumulation of riboflavin in the supernatant of shake flask cultures growing on glucose. Sequential deregulation of all the genes, by exchange of their native promoter with the strong and constitutive glyceraldehyde-3-phosphate dehydrogenase promoter (PGAP) increases the riboflavin accumulation significantly. CONCLUSION The regulation of the pathway is distributed over more than one gene. High cell density cultivations of a P. pastoris strain overexpressing all six RIB genes allow the accumulation of 175 mg/L riboflavin in the supernatant. The basis for rational engineering of riboflavin production in P. pastoris has thus been established.
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Affiliation(s)
- Hans Marx
- Institute of Applied Microbiology, Department of Biotechnology, BOKU – University of Natural Resources and Applied Life Sciences, Muthgasse 18, 1190, Wien, Austria
| | - Diethard Mattanovich
- Institute of Applied Microbiology, Department of Biotechnology, BOKU – University of Natural Resources and Applied Life Sciences, Muthgasse 18, 1190, Wien, Austria
- School of Bioengineering, FH Campus Wien – University of Applied Sciences, Muthgasse 18, 1190, Wien, Austria
| | - Michael Sauer
- Institute of Applied Microbiology, Department of Biotechnology, BOKU – University of Natural Resources and Applied Life Sciences, Muthgasse 18, 1190, Wien, Austria
- School of Bioengineering, FH Campus Wien – University of Applied Sciences, Muthgasse 18, 1190, Wien, Austria
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Fernandez Sanchez J, Blatzonis K, Backes M, Marx H. Bildgebung der Nebenmilz und deren Differentialdiagnose. ROFO-FORTSCHR RONTG 2008. [DOI: 10.1055/s-2008-1074032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
The introduction of economic production processes for 1,3-propanediol is a success story for the creation of a new market for a (bulk) chemical. The compound and its favorable properties have long been known; also the fermentation of glycerol to 1,3-propanediol had been described more than 120 years ago. Nevertheless, the product remained a specialty chemical until recently, when two new processes were introduced, providing 1,3-propanediol at a competitive price. Remarkably, one of the processes is in the field of white biotechnology and based on microbial fermentation, converting a renewable carbon source into a bulk chemical. This review covers the most important patents that led to the commercialization of bio-based 1,3-propanediol. Furthermore, some of the recent developments towards a sustainable industry are addressed. Similar questions arise for a variety of products if they are to be produced bio-based in large scale. However, special emphasis is given to 1,3-propanediol production.
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Affiliation(s)
- Michael Sauer
- School of Bioengineering, FH Campus Wien-University of Applied Sciences, Muthgasse 18, 1190 Vienna, Austria.
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Sun VC, Nelson R, Wagman B, Carroll M, Lee B, Marx H, Yen Y, Wagman LD. Quality of life in colorectal cancer patients with hepatic arterial infusion (HAI) pumps. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.19602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
19602 Background: More than half of patients diagnosed with colorectal cancer will develop hepatic metastases. Most patients with hepatic metastases will recur within two years after resection. Hepatic arterial infusion (HAI) pumps deliver regional treatment. However, very few studies quantitatively explore the patient's experience of living with an HAI pump and how this experience impacts HAI-related quality of life (QOL). This study explored the impact of HAI pump treatment on patient's overall QOL within the specific domains of physical, psychological, social, and functional well-being. Methods: Twenty-five colorectal cancer patients treated with HAI pumps completed an HAI pump- specific QOL assessment tool at one data collection time point. The QOL assessment tool items were derived from the investigator's previous QOL research with this patient population [Blair et al., 2002, Annals of Surgical Oncology]. Demographic, disease and QOL data were summarized using descriptive statistics. Results: Of the 25 patients accrued, 32% were receiving treatments through their HAI pump and 68% were not. There were no significant difference in QOL between treatment status, gender, and age (<65 or = 65). Currently treated pump patients experienced more appetite changes (p=0.03), sleep changes (p=0.08), and more restrictions in traveling (p=0.08). Male patients had more concerns with lifting heavy items (p=0.05), while female patients had more concerns with isolation (p=0.17) and changes in the type of clothing worn (p=0.16). Younger patients had more concerns with vigorous activity (p=0.01), bending (p=0.08), and were more self-conscious of their appearance with the pump (p=0.01). Conclusions: Overall, in this study, colorectal cancer patients with HAI pumps reported good QOL and were satisfied with their overall treatment experience. Although there was no comparative statistical analysis performed in this study, several QOL concerns remain worrisome for patients. Defining these specific QOL concerns in HAI patients will enhance clinical understanding of their unique experience with this treatment modality and impact patient management. This will enable further development of educational tools and research to test interventions to support HAI patients and sustain their QOL. No significant financial relationships to disclose.
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Affiliation(s)
- V. C. Sun
- City of Hope National Medical Center, Duarte, CA
| | - R. Nelson
- City of Hope National Medical Center, Duarte, CA
| | - B. Wagman
- City of Hope National Medical Center, Duarte, CA
| | - M. Carroll
- City of Hope National Medical Center, Duarte, CA
| | - B. Lee
- City of Hope National Medical Center, Duarte, CA
| | - H. Marx
- City of Hope National Medical Center, Duarte, CA
| | - Y. Yen
- City of Hope National Medical Center, Duarte, CA
| | - L. D. Wagman
- City of Hope National Medical Center, Duarte, CA
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Marx H, Sauer M, Resina D, Vai M, Porro D, Valero F, Ferrer P, Mattanovich D. Cloning, disruption and protein secretory phenotype of theGAS1homologue ofPichia pastoris. FEMS Microbiol Lett 2006; 264:40-7. [PMID: 17020547 DOI: 10.1111/j.1574-6968.2006.00427.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The aim of the study was the identification, cloning and disruption of the GAS1 homologue of Pichia pastoris. Gas1p is a glycoprotein anchored to the outer layer of the plasma membrane through a glycosylphosphatidylinositol (GPI) anchor. Gas1p is a beta-1,3-glucanosyltransglycosylase (EC 2.4.1.-). This cross-linking enzyme highly affects the structure and permeability of the yeast cell wall. The gene coding for the GAS1 homologue of P. pastoris was cloned by PCR, and its functionality was proven in a Saccharomyces cerevisiae GAS1 null mutant. Based on the nucleotide sequence information of the P. pastoris GAS1 homologue, a disruption cassette was constructed for the knockout of the GAS1 in P. pastoris. The morphology of DeltaGAS1 P. pastoris was identical to that of S. cerevisiae GAS1 mutants. Finally, the impact of GAS1 disruption on secretion of three recombinant model proteins in P. pastoris, human trypsinogen, human serum albumin and Rhizopus oryzae lipase, was evaluated. While the disruption had no effect on the secretion of trypsinogen and albumin, the amount of lipase released from the cells was doubled.
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Affiliation(s)
- Hans Marx
- Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Vienna, Austria
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Marx H, Sauer M, Resina D, Vai M, Porro D, Valero F, Ferrer P, Mattanovich D. Disruption of the GAS1 gene of Pichia pastoris confers a supersecretory phenotype for Rhizopus oryzae lipase, but not for human trypsinogen. Microb Cell Fact 2006. [DOI: 10.1186/1475-2859-5-s1-p69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Shibata S, Yen Y, Doroshow J, Leong L, Wagman L, Marx H, Clarke K, Frankel P, Lenz H, Gandara D. Phase II study of oxaliplatin in patients with unresectable, metastatic or recurrent hepatocellular cancer. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.4161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- S. Shibata
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - Y. Yen
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - J. Doroshow
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - L. Leong
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - L. Wagman
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - H. Marx
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - K. Clarke
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - P. Frankel
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - H. Lenz
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
| | - D. Gandara
- City of Hope Natl Cancer Ctr, Duarte, CA; NIH, Washington DC; USC, Los Angeles, CA; UC Davis, Sacramento, CA
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Gehrig H, Gaußmann O, Marx H, Schwarzott D, Kluge M. Molecular phylogeny of the genus Kalanchoe (Crassulaceae) inferred from nucleotide sequences of the ITS-1 and ITS-2 regions. Plant Sci 2001; 160:827-835. [PMID: 11297779 DOI: 10.1016/s0168-9452(00)00447-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The study presents an analysis of genotypic diversity in the genus Kalanchoe (Crassulaceae) on the level of Internal Transcribed Spacer (ITS) sequences and the attempt to correlate this diversity with previous findings on ecophysiological behavior, habitat preference, infrageneric taxonomic position of the species and DNA polymorphism derived from RAPD-PCR data. The Kalanchoe species are mainly abundant in Madagascar and eastern continental Africa and perform in situ diverse modes of crassulacean acid metabolism (CAM), an ecophysiologically relevant adaptation of photosynthesis. Total DNA was extracted from 68 Kalanchoe species and varieties. The ITS-1 and ITS-2 regions of the nuclear RNA genes were amplified by polymerase chain reaction, cloned and sequenced. The alignments of the sequences were evaluated by distance (neighbor joining) and character state (maximum parsimony) methods. The main topologies of the obtained ITS phylogenetic trees were quite similar irrespective of the mode of evaluation and show: (A) within the Crassulaceae the genus Kalanchoe forms a monophyletic clade; and (B) within the genus the species form three main clusters which coincide well with the previously reported three infrageneric sections of the species distinguishable by classical taxonomic criteria, the mode of in situ CAM performance, and DNA fragment pattern obtained by RAPD-PCR analyses. Moreover, the ITS phylogenetic trees show that all African Kalanchoe species form a distinct group within the most derived of the three main clusters. This is consistent with the view that the center of phylogenetic radiation of the genus is located in Madagascar from where the species have spread into the continental Africa.
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Affiliation(s)
- H Gehrig
- Smithsonian Tropical Research Institute, Unit 0948, APO AA, 34002-0948, Panama
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Abstract
The caesarean section rate in the Royal Gwent Hospital has, as in the rest of the UK, risen significantly over the last 10 years. A commonly proposed reason for this increase is that women themselves are now more likely to request an elective caesarean section, when there is little or no medical indication. The aim of this survey, carried out prospectively, was to find out whether patients' requests for caesarean section are contributing significantly to the rise in the section rate, by attempting to actually quantify the influence of patients' choice on the decision to perform a caesarean section. The results showed that it is possible to quantify this influence, and that maternal request does play a major role in the decision-making process.
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Affiliation(s)
- H Marx
- Department of Obstetrics and Gynaecology, Royal Gwent Hospital, Newport, Wales, UK
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Winnefeld K, Streck S, Treff E, Jütte H, Kroll E, Marx H. [Reference ranges of antioxidant parameters in whole blood (erythrocytes) in a Thüringen region]. Med Klin (Munich) 1999; 94 Suppl 3:101-2. [PMID: 10554543 DOI: 10.1007/bf03042205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND The oxidant stress is characterized by measurement of the activities of glutathione peroxidase, superoxiddismutase and also by concentrations of glutathione and selenium in erythrocytes. A standardization of the methods of determination is very important. MATERIAL AND METHODS In erythrocytes of blood donors (n = 101) the parameters glutathione peroxidase, glutathione, superoxiddismutase and selenium were determined. RESULTS The following results of the antioxidant parameters in erythrocytes of blood donors were found: Selenium 67.1 +/- 20.1 nmol/mmol Hb, glutathione peroxidase 842 +/- 290 U/mmol Hb, glutathione 108 +/- 48 mumol/mmol Hb, superoxiddismutase 15.8 +/- 6.4 U/mumol Hb. CONCLUSION Selenium, glutathione peroxidase, glutathione and superoxiddismutase in erythrocytes of blood donors are normally distributed. There are no significant differences between men and women. The use of "own reference values" is necessary because no standardization of the methods of determination exists.
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Affiliation(s)
- K Winnefeld
- Institut für Klinische Chemie und Laboratoriumsdiagnostik, Friedrich-Schiller-Universität Jena.
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Schneider W, Küspert P, Roth E, Visé M, Marx H. Short- and long-term effects of training phonological awareness in kindergarten: evidence from two German studies. J Exp Child Psychol 1997; 66:311-40. [PMID: 9299078 DOI: 10.1006/jecp.1997.2384] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Two training studies replicated and extended a Scandinavian study by Lundberg, Frost, and Petersen (1988). In Study 1, a 6-month metalinguistic training program was given to kindergartners (mean age: 5 years 7 months) who were later compared to a control group in the regular kindergarten program. Tests of phonological awareness and other metalinguistic and cognitive variables were given before and after training; a metalinguistic transfer test was given after training. Reading and spelling skills were assessed at the end of Grades 1 and 2, respectively. The training program was improved and monitored more closely in Study 2. Both studies revealed short- and long-term effects, consistent with Lundberg et al. (1988) and extending findings from Anglo-American and Scandinavian populations to German children.
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Affiliation(s)
- W Schneider
- Department of Psychology, University of W-urzburg, Wurzburg, Germany
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Marx H, Brunner B, Weinzierl W, Hoffmann R, Stolle A. Methods of stunning freshwater fish: impact on meat quality and aspects of animal welfare. ACTA ACUST UNITED AC 1997. [DOI: 10.1007/s002170050078] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Stolle A, Marx H, Kühnlein C. [Evaluation of the meat quality of game]. Zentralbl Veterinarmed B 1995; 42:345-54. [PMID: 8578914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The carcasses of 140 roe deer, 129 wild boars, 81 red deer and 55 fallow deer were examined to determine meat quality with respect to the influence of typical hunting situations. After hunting, many carcasses had not been cooled, which significantly influenced meat-quality parameters. The pH-value, detected electrochemically, gave the most reliable results out of all the meat-quality parameters investigated. Determination of the pH-value with regard to the pH indexes ascertained for different points of measurement and types of game is helpful in properly judging the substantial quality of venison. Determination of electrical conductivity and water-holding capacity (Q) can be helpful in judging meat quality. The value of residual-blood content in judging substantial venison quality is, however, doubtful. The measurement of rapid glycolysis and the evaluation of rigor mortis are not appropriate for determining the substantial quality of venison.
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Affiliation(s)
- A Stolle
- Institut für Hygiene und Technologie, Lebensmittel tierischen Ursprungs, München, Deutschland
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Marx H, Gedek B, Kollarczik B. [Comparative investigations of mycotoxological status of alternatively and conventionally grown crops]. Z Lebensm Unters Forsch 1995; 201:83-6. [PMID: 7571872 DOI: 10.1007/bf01193206] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
100 samples of rye and 101 samples of wheat coming out of both conventional and alternative or ecological production were investigated for contamination with mycotoxins with interest for our degree of latitude. Deoxynivalenol (DON) was found with thin-layer-chromatography in 131 of 201 samples altogether. A top level of 1250 micrograms DON kg-1 in rye of alternative offspring was detected. The average burden in contaminated rye coming from ecological production was 427 micrograms kg-1 and a mean level of 160 micrograms kg-1 resulting in rye out of conventional growth conditions. In wheat, conventionally grown yield showed slightly lower contamination (mean levels of 420 micrograms DON kg-1 towards 486 micrograms kg-1). The toxins 3-acetyl-deoxynivalenol, nivalenol and fusarenone X were detected in some samples by thin-layer-chromatography. This results could not be confirmed by gas chromatography -mass spectrometry. Zearalenone was found in 40 out of the number of 201 samples of grain by HPLC with fluorescence detection. An average of 6 micrograms and 24 micrograms zearalenone kg-1 in conventionally and alternatively grown wheat and 4 micrograms and 51 micrograms zearalenone kg-1 in conventionally and alternatively produced rye was detected. The highest finding of zearalenone was 199 micrograms kg-1 in alternatively grown rye. Skin toxicity testing did not show any reference of contamination with type-A-trichothecenes. No correlation between contamination of zearalenone or deoxynivalenol and thousand-kernel-weight was detected.
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Affiliation(s)
- H Marx
- Institut für medizinische Mikrobiologie, Infektions- und Seuchenlehre, Ludwig-Maximilians-Universität, München, Germany
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Marx H. Comparison of the biomechanical motions and forces involved in high-profile versus low-profile dynamic splinting. J Hand Ther 1995; 8:41. [PMID: 7742899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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47
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Marx H, Gedek B, Kollarczik B. [Comparative studies of the bacterial and mycological status of ecologically and conventionally grown crops]. Z Ernahrungswiss 1994; 33:239-43. [PMID: 7810182 DOI: 10.1007/bf01610789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Wheat and rye derived from conventional and from alternative or ecological production was examined for bacterial and fungal contamination. The overall bacterial and fungal contamination was lower than 10(7.7) germs/g. The amount and type of germs in the grain corresponded to typical contamination of fresh crop. No difference in germ contamination of both conventionally and alternatively grown wheat and rye could be found. No correlation between bacterial or fungal contamination and thousand-kernel-weight was detected.
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Affiliation(s)
- H Marx
- Institut für medizinische Mikrobiologie, Infektions- und Seuchenlehre, Tierärztliche Fakultät der Ludwig-Maximilians-Universität München
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Marx H. [40 years of German Society for Prosthodontics and Material Sciences]. Dtsch Zahnarztl Z 1991; 46:646-8. [PMID: 1817852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The German Society for Prosthodontics and Material Sciences is turning 40 years this year. This event is reason enough to look back and remember its stages in development.
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Affiliation(s)
- H Marx
- Univ. Zahn-, Mund- und Keiferklinik Mainz
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Marx H. [Abrasion resistance of dental veneering materials]. Dent Labor (Munch) 1990; 38:1785-6. [PMID: 2097211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Marx H. [The problems of bonding strength tests for metal-acrylic-bonds]. Dtsch Zahnarztl Z 1988; 43:1024-7. [PMID: 3255555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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