Urs von Stockar

Summary

Country: Switzerland

Publications

  1. ncbi request reprint Thermodynamics of microbial growth and metabolism: an analysis of the current situation
    Urs von Stockar
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne EPFL, CH 1015 Lausanne, Switzerland
    J Biotechnol 121:517-33. 2006
  2. ncbi request reprint Does microbial life always feed on negative entropy? Thermodynamic analysis of microbial growth
    U von Stockar
    Laboratory of Chemical and Biochemical Engineering, Institute of Chemical Engineering, Swiss Federal Institute of Technology Lausanne EPFL, CH 1015, Lausanne, Switzerland
    Biochim Biophys Acta 1412:191-211. 1999
  3. ncbi request reprint Back to basics: thermodynamics in biochemical engineering
    U von Stockar
    Institut de Génie Chimique, Swiss Federal Institute of Technology, 1015 Lausanne, Switzerland
    Adv Biochem Eng Biotechnol 80:1-17. 2003
  4. ncbi request reprint Simplified Fourier-transform mid-infrared spectroscopy calibration based on a spectra library for the on-line monitoring of bioprocesses
    Jonas Schenk
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne, CH 1015 Lausanne, Switzerland
    Anal Chim Acta 591:132-40. 2007
  5. ncbi request reprint pH prediction and control in bioprocesses using mid-infrared spectroscopy
    Jonas Schenk
    Laboratory of Chemical and Biological Engineering, Ecole Polytechnique Federale de Lausanne, CH J2 503, Station 6, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 100:82-93. 2008
  6. ncbi request reprint Influence of specific growth rate on specific productivity and glycosylation of a recombinant avidin produced by a Pichia pastoris Mut+ strain
    Jonas Schenk
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 99:368-77. 2008
  7. doi request reprint Data reconciliation of concentration estimates from mid-infrared and dielectric spectral measurements for improved on-line monitoring of bioprocesses
    Michal Dabros
    Laboratory of Chemical and Biological Engineering, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Federale de Lausanne, CH 1015 Lausanne, Switzerland
    Biotechnol Prog 25:578-88. 2009
  8. ncbi request reprint Real-time update of calibration model for better monitoring of batch processes using spectroscopy
    Henri Kornmann
    Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 87:593-601. 2004
  9. ncbi request reprint Mixed feeds of glycerol and methanol can improve the performance of Pichia pastoris cultures: A quantitative study based on concentration gradients in transient continuous cultures
    Carmen Jungo
    Ecole Polytechnique Federale de Lausanne, Laboratoire de Génie Chimique et Biologique, Station 6, 1015 Lausanne, Switzerland
    J Biotechnol 128:824-37. 2007
  10. ncbi request reprint A quantitative analysis of the benefits of mixed feeds of sorbitol and methanol for the production of recombinant avidin with Pichia pastoris
    Carmen Jungo
    Ecole Polytechnique Federale de Lausanne, Laboratoire de Génie Chimique et Biologique, Station 6, Lausanne, Switzerland
    J Biotechnol 131:57-66. 2007

Collaborators

  • Michal Dabros
  • Christoph Herwig
  • Andrea Zocchi
  • J Liu
  • Jens Nielsen
  • Dominique Bonvin
  • T Maskow
  • Jonas Schenk
  • Carmen Jungo
  • Ian Marison
  • Ian W Marison
  • Henri Kornmann
  • Christopher Cannizzaro
  • Veronique Breguet
  • Vojislav Vojinovic
  • Martin Rhiel
  • Julien Urfer
  • Ian William Marison
  • Raphaël Gugerli
  • Sergio Valentinotti
  • Philippe Duboc
  • Daniel Stark
  • Anna Marya Jobé
  • Sven Olaf Enfors
  • Krisztina Balazs
  • Carla Viscasillas
  • Carole Wegmann
  • Muriel Pasquier
  • Bjarke Christensen
  • Luuk van der Wielen
  • Bernhard Walker
  • Martin Surzyn
  • Ivan Bolzonella
  • Paul Ducommun

Detail Information

Publications30

  1. ncbi request reprint Thermodynamics of microbial growth and metabolism: an analysis of the current situation
    Urs von Stockar
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne EPFL, CH 1015 Lausanne, Switzerland
    J Biotechnol 121:517-33. 2006
    ..Potential sources for errors have been analyzed and can be used to identify the most important needs for future research...
  2. ncbi request reprint Does microbial life always feed on negative entropy? Thermodynamic analysis of microbial growth
    U von Stockar
    Laboratory of Chemical and Biochemical Engineering, Institute of Chemical Engineering, Swiss Federal Institute of Technology Lausanne EPFL, CH 1015, Lausanne, Switzerland
    Biochim Biophys Acta 1412:191-211. 1999
    ..The ratio of enthalpy change and Gibbs energy change can also be predicted since it is shown to be approximately equal to the same ratio of the relevant catabolic process alone...
  3. ncbi request reprint Back to basics: thermodynamics in biochemical engineering
    U von Stockar
    Institut de Génie Chimique, Swiss Federal Institute of Technology, 1015 Lausanne, Switzerland
    Adv Biochem Eng Biotechnol 80:1-17. 2003
    ..The present contribution uses the course structure to provide an outline of the area and to characterize very briefly the achievements, the challenges, and the research needs in the various sub-topics...
  4. ncbi request reprint Simplified Fourier-transform mid-infrared spectroscopy calibration based on a spectra library for the on-line monitoring of bioprocesses
    Jonas Schenk
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne, CH 1015 Lausanne, Switzerland
    Anal Chim Acta 591:132-40. 2007
    ..Even though simple, this method allows more advanced calculations, such as determination of the explained variance and detection of unexpected compounds using residuals analysis...
  5. ncbi request reprint pH prediction and control in bioprocesses using mid-infrared spectroscopy
    Jonas Schenk
    Laboratory of Chemical and Biological Engineering, Ecole Polytechnique Federale de Lausanne, CH J2 503, Station 6, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 100:82-93. 2008
    ..12 pH units, and the technique was fast enough to implement a feedback controller to maintain the pH constant during cultivation...
  6. ncbi request reprint Influence of specific growth rate on specific productivity and glycosylation of a recombinant avidin produced by a Pichia pastoris Mut+ strain
    Jonas Schenk
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 99:368-77. 2008
    ..In terms of process optimization, this suggests that a compromise on the specific growth rate may have to be found, in certain cases, to work with an acceptable productivity while avoiding the addition of many mannoses...
  7. doi request reprint Data reconciliation of concentration estimates from mid-infrared and dielectric spectral measurements for improved on-line monitoring of bioprocesses
    Michal Dabros
    Laboratory of Chemical and Biological Engineering, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Federale de Lausanne, CH 1015 Lausanne, Switzerland
    Biotechnol Prog 25:578-88. 2009
    ..It is verified experimentally that the proposed approach reduces the standard error of prediction without the need for additional off-line analysis...
  8. ncbi request reprint Real-time update of calibration model for better monitoring of batch processes using spectroscopy
    Henri Kornmann
    Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 87:593-601. 2004
    ..11, 0.37, and 0.79 g/L for fructose, acetate, and gluconacetan, respectively. Therefore, the proposed algorithm is a valuable approach to reduce the calibration time of multiwavelength optical sensors...
  9. ncbi request reprint Mixed feeds of glycerol and methanol can improve the performance of Pichia pastoris cultures: A quantitative study based on concentration gradients in transient continuous cultures
    Carmen Jungo
    Ecole Polytechnique Federale de Lausanne, Laboratoire de Génie Chimique et Biologique, Station 6, 1015 Lausanne, Switzerland
    J Biotechnol 128:824-37. 2007
    ..Results obtained in a high cell density fed-batch culture with a mixed feed of 0.65 C-mol C-mol(-1) methanol and 0.35 C-mol C-mol(-1) glycerol were in agreement with results obtained during the transient nutrient gradient...
  10. ncbi request reprint A quantitative analysis of the benefits of mixed feeds of sorbitol and methanol for the production of recombinant avidin with Pichia pastoris
    Carmen Jungo
    Ecole Polytechnique Federale de Lausanne, Laboratoire de Génie Chimique et Biologique, Station 6, Lausanne, Switzerland
    J Biotechnol 131:57-66. 2007
    ....
  11. doi request reprint Cole-Cole, linear and multivariate modeling of capacitance data for on-line monitoring of biomass
    Michal Dabros
    Laboratory of Chemical and Biological Engineering LGCB, Ecole Polytechnique Federale de Lausanne EPFL, Station 6, 1015 Lausanne, Switzerland
    Bioprocess Biosyst Eng 32:161-73. 2009
    ..In less noisy conditions, the three models performed similarly. Estimates of the mean cell size were done additionally using the Cole-Cole and PLS models, the latter technique giving more satisfactory results...
  12. ncbi request reprint On-line biomass monitoring of CHO perfusion culture with scanning dielectric spectroscopy
    Christopher Cannizzaro
    Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 84:597-610. 2003
    ..34 microm (2%). Upon extension to a subsequent experiment (B16), the predicted error was 1.18 microm (9%)...
  13. ncbi request reprint Regulation of alcohol oxidase of a recombinant Pichia pastoris Mut+ strain in transient continuous cultures
    Carmen Jungo
    Ecole Polytechnique Federale de Lausanne, Laboratoire de Génie Chimique et Biologique, Station 6, CH 1015 Lausanne, Switzerland
    J Biotechnol 130:236-46. 2007
    ..High rate of methanol consumption was due to high specific AOX activities observed at low residual methanol concentrations...
  14. doi request reprint On-line monitoring of nine different batch cultures of E. coli by mid-infrared spectroscopy, using a single spectra library for calibration
    Jonas Schenk
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne EPFL, CH 1015 Lausanne, Switzerland
    J Biotechnol 134:93-102. 2008
    ....
  15. ncbi request reprint On-line monitoring of Phaffia rhodozyma fed-batch process with in situ dispersive Raman spectroscopy
    Christopher Cannizzaro
    Laboratory of Chemical and Biochemical Engineering, Department of Chemistry, Swiss Federal Institute of Technology EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 83:668-80. 2003
    ....
  16. ncbi request reprint Generally applicable fed-batch culture concept based on the detection of metabolic state by on-line balancing
    Anna Marya Jobé
    Laboratory of Chemical and Biological Engineering, Swiss Federal Institute of Technology Lausanne EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 82:627-39. 2003
    ..These data certainly help the operator to additionally evaluate the state of the process on-line...
  17. ncbi request reprint On-line recalibration of spectral measurements using metabolite injections and dynamic orthogonal projection
    Michal Dabros
    Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Federale de Lausanne, Station 6, Lausanne, Switzerland
    Appl Spectrosc 61:507-13. 2007
    ..Applying this technique led to a noticeable decrease in the standard error of prediction of metabolite concentrations monitored during an anaerobic fermentation of the yeast Saccharomyces cerevisiae...
  18. ncbi request reprint A simple method to monitor and control methanol feeding of Pichia pastoris fermentations using mid-IR spectroscopy
    Jonas Schenk
    Laboratory of Chemical and Biochemical Engineering LGCB, Station 6 CH J2 503, Ecole Polytechnique Federale de Lausanne EPFL, CH 1015 Lausanne, Switzerland
    J Biotechnol 128:344-53. 2007
    ..12gl(-1). Even though methanol acts both as carbon source and inducer of protein expression, no significant effect was observed on the level of protein expression in the recombinant strain used...
  19. ncbi request reprint In situ product removal (ISPR) in whole cell biotechnology during the last twenty years
    Daniel Stark
    Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology EPFL, 1015 Lausanne, Switzerland
    Adv Biochem Eng Biotechnol 80:149-75. 2003
    ..Furthermore, additional process aspects, biological and legal constraint need to be considered from the very beginning for the design of an ISPR project. Finally, future trends of new, modified or improved ISPR techniques are given...
  20. ncbi request reprint Optimisation of culture conditions with respect to biotin requirement for the production of recombinant avidin in Pichia pastoris
    Carmen Jungo
    Ecole Polytechnique Federale de Lausanne, Laboratoire de Génie Chimique et Biologique, Station 6, CH 1015 Lausanne, Switzerland
    J Biotechnol 127:703-15. 2007
    ..The specific avidin production rate was 22 microg g(-1) h(-1) at a dilution rate of 0.06 h(-1)...
  21. pmc Influence of nutritional factors on the nature, yield, and composition of exopolysaccharides produced by Gluconacetobacter xylinus I-2281
    Henri Kornmann
    Laboratory of Chemical and Biological Engineering, Institute of Chemical Engineering, Swiss Federal Institute of Technology Lausanne EPFL, CH 1015 Lausanne, Switzerland
    Appl Environ Microbiol 69:6091-8. 2003
    ....
  22. doi request reprint Influence of uncertainties in pH, pMg, activity coefficients, metabolite concentrations, and other factors on the analysis of the thermodynamic feasibility of metabolic pathways
    Vojislav Vojinovic
    Laboratory of Chemical and Biological Engineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
    Biotechnol Bioeng 103:780-95. 2009
    ..It also suggests an urgent need for experimental determinations of such factors as a prerequisite for sensible thermodynamic analysis of metabolism on a genome-wide scale...
  23. ncbi request reprint Metabolic network analysis on Phaffia rhodozyma yeast using 13C-labeled glucose and gas chromatography-mass spectrometry
    Christopher Cannizzaro
    Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology EPFL, CH 1015 Lausanne, Switzerland
    Metab Eng 6:340-51. 2004
    ..The central carbon metabolism of the mutant strain was similar to that of the wildtype strain, though the relative pentose phosphate flux was lower and the TCA cycle flux in accordance with the biomass yield being lower...
  24. ncbi request reprint Quantitative comparison of transient growth of Saccharomyces cerevisiae, Saccharomyces kluyveri, and Kluyveromyces lactis
    Christoph Herwig
    Laboratory of Chemical and Biochemical Engineering, Swiss Federal Institute of Technology Lausanne EPFL, CH 1015 Lausanne, Switzerland
    Biotechnol Bioeng 81:837-47. 2003
    ..Used in an online context, this approach serves as an efficient tool for strain characterization and physiological studies...
  25. pmc CHO immobilization in alginate/poly-L: -lysine microcapsules: an understanding of potential and limitations
    Veronique Breguet
    Laboratory of Biological and Chemical Engineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
    Cytotechnology 53:81-93. 2007
    ..This was confirmed by experiments showing reduced growth rates of batch suspension cultures of CHO cells in medium containing dissolved alginate. Removal of this alginate would therefore be expected to increase microcapsule colonization...
  26. ncbi request reprint Real-time in situ monitoring of freely suspended and immobilized cell cultures based on mid-infrared spectroscopic measurements
    Martin Rhiel
    Laboratory of Chemical and Biochemical Engineering LGCB, Swiss Federal Institute of Technology Lausanne EPFL, 1015 Lausanne, Switzerland
    Biotechnol Bioeng 77:174-85. 2002
    ..The sensor system proved to be reliable, simple, accurate, sterile, and capable of long-term automatic operation and is considered to be mature enough to be routinely applied for in situ (on-line) cell culture monitoring...
  27. ncbi request reprint Monitoring and control of Gluconacetobacter xylinus fed-batch cultures using in situ mid-IR spectroscopy
    Henri Kornmann
    Serono Biotech Center, route de Fenil, ZI B, CH 1809 Fenil sur Corsier, Switzerland
    J Biotechnol 113:231-45. 2004
    ..In this way, the productivity of gluconacetan was increased from 1.8 x 10(-3) [C-mol/C-mol substrate/h] in the batch process to 2.9 x 10(-3) [C-mol/C-mol substrate/h] in the fed-batch process described in this study...
  28. ncbi request reprint How reliable are thermodynamic feasibility statements of biochemical pathways?
    Thomas Maskow
    Department of Environmental Microbiology, UFZ Centre for Environmental Research Leipzig Halle GmbH, Germany
    Biotechnol Bioeng 92:223-30. 2005
    ....
  29. ncbi request reprint Enzymatic hydrolysis of organic-core microcapsules to produce aqueous-core microcapsules
    Veronique Breguet
    Laboratory of Biological and Chemical Engineering, Ecole Polytechnique Federale de Lausanne, Switzerland
    J Microencapsul 25:179-86. 2008
    ..Under these conditions, incubation of tripropionin-alginate microcapsules in a buffer containing the enzyme successfully produced aqueous-core capsules with reduced accumulation of alginate in the core in approximately 3 h...
  30. ncbi request reprint Process integration challenges in biotechnology yesterday, today and tomorrow
    Sven Olaf Enfors
    Adv Biochem Eng Biotechnol 80:IX-XV. 2003