1
|
Tang E, Shen X, Wang J, Sun X, Yuan Q. Synergetic utilization of glucose and glycerol for efficient myo-inositol biosynthesis. Biotechnol Bioeng 2020; 117:1247-1252. [PMID: 31903546 DOI: 10.1002/bit.27263] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [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: 10/09/2019] [Revised: 01/01/2020] [Accepted: 01/02/2020] [Indexed: 02/04/2023]
Abstract
myo-Inositol (MI) as a dietary supplement can provide various health benefits. One major challenge to its efficient biosynthesis is to achieve proper distribution of carbon flux between growth and production. Herein, this challenge was overcome by synergetic utilization of glucose and glycerol. Specifically, glycerol was catabolized to support cell growth while glucose was conserved as the building block for MI production. Growth and production were coupled via the phosphotransferase system, and both modules were optimized to achieve efficient production. First, the optimal enzyme combination was established for the production module. It was observed that enhancing the production module resulted in both increased MI production and better cell growth. In addition, glucose was shown to inhibit glycerol utilization via carbon catabolite repression and the inhibition was released by over-expressing glycerol kinase. Furthermore, the inducible promoter was replaced by strong constitutive promoters to avoid inducer use. With these efforts, the final strain produced MI with both high titer and yield. In fed-batch cultivation, 76 g/L of MI was produced, showing scale-up potential. This study provides a promising strategy to achieve rational distribution of carbon flux.
Collapse
Affiliation(s)
- Erju Tang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Xiaolin Shen
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Jia Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Xinxiao Sun
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Qipeng Yuan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| |
Collapse
|
2
|
Shilyashki G, Pfützner H, Palkovits M, Windischhofer A, Giefing M. 3D-Printed Detector Band for Magnetic Off-Plane Flux Measurements in Laminated Machine Cores. Sensors (Basel) 2017; 17:s17122953. [PMID: 29257063 PMCID: PMC5750794 DOI: 10.3390/s17122953] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [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: 11/07/2017] [Revised: 12/06/2017] [Accepted: 12/07/2017] [Indexed: 11/16/2022]
Abstract
Laminated soft magnetic cores of transformers, rotating machines etc. may exhibit complex 3D flux distributions with pronounced normal fluxes (off-plane fluxes), perpendicular to the plane of magnetization. As recent research activities have shown, detections of off-plane fluxes tend to be essential for the optimization of core performances aiming at a reduction of core losses and of audible noise. Conventional sensors for off-plane flux measurements tend to be either of high thickness, influencing the measured fluxes significantly, or require laborious preparations. In the current work, thin novel detector bands for effective and simple off-plane flux detections in laminated machine cores were manufactured. They are printed in an automatic way by an in-house developed 3D/2D assembler. The latter enables a unique combination of conductive and non-conductive materials. The detector bands were effectively tested in the interior of a two-package, three-phase model transformer core. They proved to be mechanically resilient, even for strong clamping of the core.
Collapse
Affiliation(s)
- Georgi Shilyashki
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Gußhausstraße 25/354, 1040 Vienna, Austria.
| | - Helmut Pfützner
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Gußhausstraße 25/354, 1040 Vienna, Austria.
| | - Martin Palkovits
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Gußhausstraße 25/354, 1040 Vienna, Austria.
| | - Andreas Windischhofer
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Gußhausstraße 25/354, 1040 Vienna, Austria.
| | - Markus Giefing
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Gußhausstraße 25/354, 1040 Vienna, Austria.
| |
Collapse
|
3
|
Shirai T, Ishizawa M, Zhuravlev R, Ganshin A, Belikov D, Saito M, Oda T, Valsala V, Gomez-Pelaez AJ, Langenfelds R, Maksyutov S. A decadal inversion of CO 2 using the Global Eulerian-Lagrangian Coupled Atmospheric model (GELCA): sensitivity to the ground-based observation network. Tellus B Chem Phys Meteorol 2017; 69:1291158. [PMID: 32848290 PMCID: PMC7447134 DOI: 10.1080/16000889.2017.1291158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present an assimilation system for atmospheric carbon dioxide (CO2) using a Global Eulerian-Lagrangian Coupled Atmospheric model (GELCA), and demonstrate its capability to capture the observed atmospheric CO2 mixing ratios and to estimate CO2 fluxes. With the efficient data handling scheme in GELCA, our system assimilates non-smoothed CO2 data from observational data products such as the Observation Package (ObsPack) data products as constraints on surface fluxes. We conducted sensitivity tests to examine the impact of the site selections and the prior uncertainty settings of observation on the inversion results. For these sensitivity tests, we made five different site/data selections from the ObsPack product. In all cases, the time series of the global net CO2 flux to the atmosphere stayed close to values calculated from the growth rate of the observed global mean atmospheric CO2 mixing ratio. At regional scales, estimated seasonal CO2 fluxes were altered, depending on the CO2 data selected for assimilation. Uncertainty reductions (URs) were determined at the regional scale and compared among cases. As measures of the model-data mismatch, we used the model-data bias, root-mean-square error, and the linear correlation. For most observation sites, the model-data mismatch was reasonably small. Regarding regional flux estimates, tropical Asia was one of the regions that showed a significant impact from the observation network settings. We found that the surface fluxes in tropical Asia were the most sensitive to the use of aircraft measurements over the Pacific, and the seasonal cycle agreed better with the results of bottom-up studies when the aircraft measurements were assimilated. These results confirm the importance of these aircraft observations, especially for constraining surface fluxes in the tropics.
Collapse
Affiliation(s)
- T Shirai
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - M Ishizawa
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - R Zhuravlev
- Central Aerological Observatory, Dolgoprudny, Russia
| | - A Ganshin
- Central Aerological Observatory, Dolgoprudny, Russia
| | - D Belikov
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
- Tomsk State University, Tomsk, Russia
- National Institute of Polar Research, Tachikawa, Japan
| | - M Saito
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - T Oda
- Goddard Earth Sciences Technology and Research, Universities Space Research Association, Columbia, MD, USA / Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - V Valsala
- Indian Institute for Tropical Meteorology
| | - A J Gomez-Pelaez
- Izaña Atmospheric Research Center, Meteorological State Agency of Spain, Izaña, Spain
| | - R Langenfelds
- Oceans and Atmosphere Flagship, Commonwealth Scientific and Industrial Research Organization, Aspendale, Australia
| | - S Maksyutov
- Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba, Japan
| |
Collapse
|