(369c) Seeding Strategies for the Selective Crystallisation of Model Proteins

The recognition of the selective nature of biopharmaceutical drugs and the advances in biotechnology have led to over 246 approved products with cumulative revenues reaching $140 billion [1]. Upstream biomanufacture of proteins has advanced, such that the time and expense bottleneck in biopharmaceutics lies in the chromatographic purification steps [3-5]. Crystallisation is a more economic and energy efficient alternative purification step, producing crystalline proteins with higher purity and stability [3, 6]. However, this technology is yet to mature to manufacturing scale and robustness.

Here, we report our optimised crystallisation, additive and seeding strategies to crystallise model proteins and demonstrate selective crystallisation of target proteins from a binary mixture.

Mesoporous silica nanoparticles (NPs) are shown to be effective heterogenous nucleants for the selective crystallisation of lysozyme from a binary mixture of lysozyme and thaumatin. From hanging drop solution conditions which can crystallise both proteins, the ‘hard template’ SBA-15 NPs are found to not only promote the nucleation of lysozyme, but also suppress the crystallisation of thaumatin. These conditions are also effectively scaled up to the ml level. Further to this, the effectiveness of graphene oxides and DNA polymeric additives are also examined as seeds for protein crystallisation promotion.

Here, we report on the use of several templating strategies for the crystallisation of proteins demonstrating the feasibility for selective crystallisation of proteins for downstream separations.

ACKNOWLEDGEMENT

This study acknowledges by the SCoBiC project funded by the UK’s EPSRC (EP/N015916/1).

References

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