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Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions

BACKGROUND: The utilization of methane for production of Poly-β-hydroxybutyrate (PHB) not only cuts the emissions of greenhouse gases but also greatly reduces PHB production cost. OBJECTIVES: The aim of this study was to determine the effects of gas-phase conditions on PHB production by Methylosinus...

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Autores principales: Zhang, Tingting, Zhou, Jiti, Wang, Xiaowei, Zhang, Yu
Formato: Online Artículo Texto
Lenguaje:English
Publicado: National Institute of Genetic Engineering and Biotechnology 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6697861/
https://www.ncbi.nlm.nih.gov/pubmed/31457042
http://dx.doi.org/10.21859/ijb.1866
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author Zhang, Tingting
Zhou, Jiti
Wang, Xiaowei
Zhang, Yu
author_facet Zhang, Tingting
Zhou, Jiti
Wang, Xiaowei
Zhang, Yu
author_sort Zhang, Tingting
collection PubMed
description BACKGROUND: The utilization of methane for production of Poly-β-hydroxybutyrate (PHB) not only cuts the emissions of greenhouse gases but also greatly reduces PHB production cost. OBJECTIVES: The aim of this study was to determine the effects of gas-phase conditions on PHB production by Methylosinus trichosporium OB(3)b. MATERIALS AND METHODS: Bacterial cultivation and PHB production were conducted in a series of sealed serum bottles. Nitrogen-free mineral salts medium was used to induce PHB production in the presence or absence of N(2) in the headspace. RESULTS: In the absence of N(2), the highest PHB content (i.e., 52.9% of the dry cell weight with a PHB concentration of 814.3 mg.L(-1)) was obtained at a ratio of CH(4):O(2)=2:1. Further study at different O(2) concentrations with a fixed CH(4) partial pressure in absence of N(2) showed that PHB accumulation by methanotroph could be tolerated high oxygen partial pressure and its respond to the variation of the oxygen concentration depends on the methane partial pressure. In presence of N(2), with headspace gas replenished only when oxygen was almost depleted, the degradation of intracellular PHB has appeared. In the regimen of updating headspace gas at the point when the PHB content began to decrease, the highest PHB content (i.e., 55.5% of the dry cell weight with 901.8 mg.L(-1) PHB concentration and 12.5 mg.L(-1).h(-1)PHB productivity) was obtained at 0.2 atm O(2) and PHB accumulation was depressed with an oxygen concentration greater than 0.3 atm. CONCLUSIONS: The methanotroph responses differentially to the increase in the oxygen partial pressure with regard to PHB accumulation either in the presence or in the absence of N2.
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spelling pubmed-66978612019-08-27 Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions Zhang, Tingting Zhou, Jiti Wang, Xiaowei Zhang, Yu Iran J Biotechnol Research Article BACKGROUND: The utilization of methane for production of Poly-β-hydroxybutyrate (PHB) not only cuts the emissions of greenhouse gases but also greatly reduces PHB production cost. OBJECTIVES: The aim of this study was to determine the effects of gas-phase conditions on PHB production by Methylosinus trichosporium OB(3)b. MATERIALS AND METHODS: Bacterial cultivation and PHB production were conducted in a series of sealed serum bottles. Nitrogen-free mineral salts medium was used to induce PHB production in the presence or absence of N(2) in the headspace. RESULTS: In the absence of N(2), the highest PHB content (i.e., 52.9% of the dry cell weight with a PHB concentration of 814.3 mg.L(-1)) was obtained at a ratio of CH(4):O(2)=2:1. Further study at different O(2) concentrations with a fixed CH(4) partial pressure in absence of N(2) showed that PHB accumulation by methanotroph could be tolerated high oxygen partial pressure and its respond to the variation of the oxygen concentration depends on the methane partial pressure. In presence of N(2), with headspace gas replenished only when oxygen was almost depleted, the degradation of intracellular PHB has appeared. In the regimen of updating headspace gas at the point when the PHB content began to decrease, the highest PHB content (i.e., 55.5% of the dry cell weight with 901.8 mg.L(-1) PHB concentration and 12.5 mg.L(-1).h(-1)PHB productivity) was obtained at 0.2 atm O(2) and PHB accumulation was depressed with an oxygen concentration greater than 0.3 atm. CONCLUSIONS: The methanotroph responses differentially to the increase in the oxygen partial pressure with regard to PHB accumulation either in the presence or in the absence of N2. National Institute of Genetic Engineering and Biotechnology 2019-01-11 /pmc/articles/PMC6697861/ /pubmed/31457042 http://dx.doi.org/10.21859/ijb.1866 Text en Copyright © 2019 The Author(s); Published by National Institute of Genetic Engineering and Biotechnology. http://creativecommons.org/licenses/by-nc/4.0/ This is an open access article, distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits others to copy and redistribute material just in noncommercial usages, provided the original work is properly cited.
spellingShingle Research Article
Zhang, Tingting
Zhou, Jiti
Wang, Xiaowei
Zhang, Yu
Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions
title Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions
title_full Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions
title_fullStr Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions
title_full_unstemmed Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions
title_short Poly-β-hydroxybutyrate Production by Methylosinus trichosporium OB3b at Different Gas-phase Conditions
title_sort poly-β-hydroxybutyrate production by methylosinus trichosporium ob3b at different gas-phase conditions
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6697861/
https://www.ncbi.nlm.nih.gov/pubmed/31457042
http://dx.doi.org/10.21859/ijb.1866
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