Construction of efficient xylose utilizing Pichia pastoris for industrial enzyme production. Issue 1 (December 2015)

• Record Type: Journal Article
• Authors: Li, Pengfei; Sun, Hongbing; Chen, Zao; Li, Yin; Zhu, Taicheng
• Is Part Of: Microbial cell factories. Volume 14:Issue 1(2015)
• Page Start: 1
• Page End: 10
• Publication Date: 2015-12
• Subjects: Xylose -- Xylose isomerase -- Recombinant Pichia pastoris -- Evolutionary engineering -- Industrial enzymes; Microbial biotechnology -- Periodicals; Recombinant proteins -- Synthesis -- Periodicals; 660.62
• DOI: 10.1186/s12934-015-0206-8
• Languages: English
• ISSNs: 1475-2859

Abstract

Abstract Background Cellulosic biomass especially agricultural/wood residues can be utilized as feedstock to cost-effectively produce fuels, chemicals and bulk industrial enzymes, which demands xylose utilization from microbial cell factories. While previous works have made significant progress in improving microbial conversion of xylose into fuels and chemicals, no study has reported the engineering of efficient xylose utilizing protein expression systems for the purpose of producing industrial enzymes. Results In this work, usingPichia pastoris as an example, we demonstrated the successful engineering of xylose metabolizing ability into of protein expression systems. A heterologous XI (xylose isomerase) pathway was introduced intoP. pastoris GS115 by overexpressing theOrpinomyces spp. XI or/and the endogenous XK (xylulokinase) gene, and evolutionary engineering strategies were also applied. Results showed that the XI pathway could be functionally expressed inP. pastoris . After 50 generation of sequential batch cultivation, a set of domesticated recombinantP. pastoris strains with different performance metrics on xylose were obtained. One evolved strain showed the highest xylose assimilation ability, whose cell yield on xylose can even be comparable to that on glucose or glycerol. This strain also showed significantly increased β-mannanase production when cultured on xylose medium. Furthermore, transcription analysis of xylose pathway genes suggested that overexpression of XI and XK might be the key factors affecting effective xylose assimilation. Conclusions To our best knowledge, this study is the first work demonstrating the construction of efficient xylose utilizingP. pastoris strains, thus providing a basis for using cellulosic biomass for bulk industrial enzyme production.