Accelerated production of α2,8- and α2,9-linked polysialic acid in recombinant Escherichia coli using high cell density cultivation

Bastian Bartling; Nora C Brüchle; Johanna S Rehfeld; Daniel Boßmann; Timm Fiebig; Christa Litschko; Jörg Fohrer; Rita Gerardy-Schahn; Thomas Scheper; Sascha Beutel

doi:10.1016/j.btre.2020.e00562

Accelerated production of α2,8- and α2,9-linked polysialic acid in recombinant Escherichia coli using high cell density cultivation

Biotechnol Rep (Amst). 2020 Nov 18:28:e00562. doi: 10.1016/j.btre.2020.e00562. eCollection 2020 Dec.

Affiliations

¹ Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany.
² Institute of Clinical Biochemistry, Hannover Medical School, D-30625 Hannover, Germany.
³ Institute of Organic Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany.

Abstract

Polysialic acid (polySia) are α2,8- and/or α2,9-linked homopolymers with interesting properties for meningococcal vaccine development or the cure of human neurodegenerative disorders. With the goal to avoid large scale production of pathogenic bacteria, we compare in the current study the efficacy of conventional polySia production to recombinant approaches using the engineered laboratory safety strain E. coli BL21. High cell density cultivation (HCDC) experiments were performed in two different bioreactor systems. Increased cell densities of up to 11.3 (±0.4) g/L and polySia concentrations of up to 774 (±18) mg/L were reached in E. coli K1. However, cultivation of engineered E. coli BL21 strains delivered comparable cell densities but a maximum of only 133 mg/L polySia. Using established downstream procedures, host cell DNA and proteins were removed. All recombinant polySia products showed an identical degree of polymerization >90. Polymers with different glycosidic linkages could be successfully differentiated by nuclear magnetic resonance spectroscopy.

Keywords: Escherichia coli; High cell density; NMR spectroscopy; Polysialic acid.