Cultivation strategies for production of (R)-3-hydroxybutyric acid from simultaneous consumption of glucose, xylose and arabinose by Escherichia coli

Microbial Cell Factories

Research

Jorge Quillaguamán¹  Johan Jarmander²  Gustav Sjöberg²  Gen Larsson²  Jaroslav Belotserkovsky²  Mariel Pérez-Zabaleta³  Mónica Guevara-Martínez³ 

[1] Center of Biotechnology, Faculty of Science and Technology, Universidad Mayor de San Simón, Cochabamba, Bolivia;School of Biotechnology, Division of Industrial Biotechnology, KTH Royal Institute of Technology, SE 106 91, Stockholm, Sweden;School of Biotechnology, Division of Industrial Biotechnology, KTH Royal Institute of Technology, SE 106 91, Stockholm, Sweden;Center of Biotechnology, Faculty of Science and Technology, Universidad Mayor de San Simón, Cochabamba, Bolivia;

关键词: Escherichia coli;    3-Hydroxybutyric acid;    3HB;    Simultaneous uptake;    Lignocellulose;    Production process;    Nitrogen limitation;   

DOI  :  10.1186/s12934-015-0236-2

 received in 2014-12-11, accepted in 2015-03-30,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundLignocellulosic waste is a desirable biomass for use in second generation biorefineries. Up to 40% of its sugar content consist of pentoses, which organisms either take up sequentially after glucose depletion, or not at all. A previously described Escherichia coli strain, PPA652ara, capable of simultaneous consumption of glucose, xylose and arabinose was in the present work utilized for production of (R)-3-hydroxybutyric acid (3HB) from a mixture of glucose, xylose and arabinose.ResultsThe Halomonas boliviensis genes for 3HB production were for the first time cloned into E. coli PPA652ara, leading to product secretion directly into the medium. Process design was based on comparisons of batch, fed-batch and continuous cultivation, where both excess and limitation of the carbon mixture was studied. Carbon limitation resulted in low specific productivity of 3HB (<2 mg g−1 h−1) compared to carbon excess (25 mg g−1 h−1), but the yield of 3HB/cell dry weight (Y3HB/CDW) was very low (0.06 g g−1) during excess. Nitrogen-exhausted conditions could be used to sustain a high specific productivity (31 mg g−1 h−1) and to increase the yield of 3HB/cell dry weight to 1.38 g g−1. Nitrogen-limited fed-batch process design led to further increased specific productivity (38 mg g−1 h−1) but also to additional cell growth (Y3HB/CDW = 0.16 g g−1). Strain PPA652ara did under all processing conditions simultaneously consume glucose, xylose and arabinose, which was not the case for a reference wild type E. coli, which also gave a higher carbon flux to acetic acid.ConclusionsIt was demonstrated that by using E. coli PPA652ara, it was possible to design a production process for 3HB from a mixture of glucose, xylose and arabinose where all sugars were consumed. An industrial 3HB production process is proposed to be divided into a growth and a production phase, and nitrogen depletion/limitation is a potential strategy to maximize the yield of 3HB/CDW in the latter. The specific productivity of 3HB reported here from glucose, xylose and arabinose by E. coli is further comparable to the current state of the art for production from glucose sources.

【 授权许可】

Unknown   
© Jarmander et al.; licensee BioMed Central. 2015. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.