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bioRxiv · 10.1101/2024.09.15.612864

The lack of trade-off between conformational stability and binding affinity in a nanobody with therapeutic potential for a misfolding disease

Gomez-Mulas, A.·Naganathan, A. N.·Pey, A. L.
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Abstract

To improve protein pharmaceuticals, we need to balance protein stability and binding affinity with in vivo efficiency. We have recently developed a nanobody (NB-AGT-2) against the alanine:glyoxylate aminotransferase with high stability (Tm[~]85{degrees}C) that may be useful to treat a misfolding disease called primary hyperoxaluria type 1. In this work, we characterize the relationships between protein stability and binding affinity in NB-AGT-2 by generating single and double cavity-creating mutants in its hydrophobic core. These mutations decrease thermal stability by 10-20 {degrees}C, reflecting changes in thermodynamic stability of up to 8 kcal{middle dot}mol-1, hardly affecting their binding affinity for its target. Our results thus show that NB stability can be challenged without an effect on its binding.

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Gomez-Mulas, A., Naganathan, A. N., Pey, A. L.. 2024-09-19. The lack of trade-off between conformational stability and binding affinity in a nanobody with therapeutic potential for a misfolding disease. https://doi.org/10.1101/2024.09.15.612864

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