A scalable biomanufacturing platform for bacterial magnetosomes


An integrated scalable platform for fermentative production and downstream processing of bacterial magnetosome products is advanced. Long magnetosome chains, high cellular magnetism, and low numbers of polyhydroxyalkanoate granules were obtained during the exponential growth phase of a two-stage continuous high cell density fermentation of M. gryphiswaldense MSR-1. Centrifugally concentrated 20% (w/v) suspensions of exponential phase cells were disrupted with high efficiency (~92%) in a single pass through a Constant Systems Cell Disruptor operated at 10 kpsi, releasing ~75% of the cellular iron. Magnetosomes were recovered in partially purified form from crude whole cell disruptates by rotor-stator high-gradient magnetic separation. Further purification/polishing was achieved by magnetically enhanced density separation in an aqueous micellar two-phase system (a new technique developed in this work as a low-cost alternative to sucrose gradient ultracentrifugation). The unoptimised 4-step process delivered highly purified magnetosomes (ca. 50 and 80-fold with respect to polyhydroxyalkanoate and protein) in >50% yield, with no evidence of crystal coat damage, acceptable reduction (~35%) in median magnetosome chain length, and magnetic properties (pot-bellied hysteresis loop, coercivity = 9.8 mT, ‘squareness’ = 0.32) expected of isolated magnetosome chains. Though demonstrated in batch mode, the platform displays potential for end-to-end continuous manufacture of future magnetosome-based products.

Publication DOI: https://doi.org/10.1016/j.fbp.2024.01.005
Divisions: College of Engineering & Physical Sciences > School of Infrastructure and Sustainable Engineering > Chemical Engineering & Applied Chemistry
College of Engineering & Physical Sciences
College of Engineering & Physical Sciences > Energy and Bioproducts Research Institute (EBRI)
Funding Information: This work was supported by the ERA-IB grant EIB.13.016 ProSeCa, funded by the UK Biotechnology & Biological Sciences Research Council (BBSRC) as grant BB/M00483X/1.
Additional Information: © 2024 The Authors. CC BY 4.0
Uncontrolled Keywords: Aqueous two-phase systems, ATPS,Bioprocess separations,Downstream processing, DSP,Magnetic nanoparticles, MNP,Magnetotactic bacteria, MTB,Purification,Food Science,Chemical Engineering(all),Biochemistry,Biotechnology
Publication ISSN: 1744-3571
Last Modified: 18 Jun 2024 16:44
Date Deposited: 23 Jan 2024 14:17
Full Text Link:
Related URLs: https://www.sci ... 0051?via%3Dihub (Publisher URL)
http://www.scop ... tnerID=8YFLogxK (Scopus URL)
PURE Output Type: Article
Published Date: 2024-03
Published Online Date: 2024-01-17
Accepted Date: 2024-01-12
Authors: Fernandez-Castane, Alfred (ORCID Profile 0000-0002-2572-7797)
Li, Hong
Ebeler, Moritz
Franzreb, Matthias
Overton, Tim W.
Thomas, Owen R.T.



Version: Accepted Version

License: Creative Commons Attribution

| Preview

Export / Share Citation


Additional statistics for this record