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bioRxiv · 10.1101/2025.05.18.654753

Backbone Assignment of a 28.5 kDa Class A Extended Spectrum β-Lactamase by High-Field, Carbon-Detected Solid-State NMR

Williams, C. G.·Wang, S.·Thome, A. F.·Warmuth, O. A.·Sakhrani, V.·Rienstra, C. M.·Mueller, L. J.
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Abstract

13C and 15N backbone chemical shift assignments are reported for the 28.5 kDa protein Toho-1 {beta}-lactamase, a Class A extended spectrum {beta}-lactamase. A very high level of assignment completeness (97% of the backbone) is enabled by the combined sensitivity and resolution gains of ultrahigh-field NMR spectroscopy (1.1 GHz), improved probe technology, and optimized pulse sequences. The assigned chemical shifts agree well with our previous solution-state NMR assignments, indicating that the secondary structure is conserved in the solid state. These assignments provide a foundation for future investigations of sidechain chemical shifts and catalytic mechanism.

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Williams, C. G., Wang, S., Thome, A. F., Warmuth, O. A., Sakhrani, V., Rienstra, C. M., Mueller, L. J.. 2025-05-19. Backbone Assignment of a 28.5 kDa Class A Extended Spectrum β-Lactamase by High-Field, Carbon-Detected Solid-State NMR. https://doi.org/10.1101/2025.05.18.654753

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