Catalysis by a rigid enzyme

Ben Bdira, F.; Waudby, C. A.; N. Volkov, A.; Schroder, S.; AB, E.; Codee, J.; Overkleeft, H. S.; Aerts, H.; van Ingen, H.; Ubbink, M.

doi:10.1101/815415

bioRxiv · 10.1101/815415

Catalysis by a rigid enzyme

Ben Bdira, F.·Waudby, C. A.·N. Volkov, A.·Schroder, S.·AB, E.·Codee, J.·Overkleeft, H. S.·Aerts, H.·van Ingen, H.·Ubbink, M.

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Abstract

Many enzymes are dynamic entities, sampling conformational states that are relevant for catalytic activity. Crystal structures of catalytic intermediates suggest, however, that not all enzymes require structural changes for activity. The single-domain enzyme xylanase from Bacillus circulans (BCX) is involved in the degradation of hemicellulose. We demonstrate that BCX in solution undergoes minimal structural changes during catalysis. NMR spectroscopy results show that the rigid protein matrix provides a frame for fast substrate binding in multiple conformations, accompanied by slow, enzyme induced substrate distortion. Therefore, we propose a model in which the rigid enzyme takes advantage of substrate flexibility to induce a conformation that facilitates catalysis.\n\nOne Sentence SummaryThe rigid matrix of BCX uses substrate flexibility in Michaelis complex formation.

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Ben Bdira, F., Waudby, C. A., N. Volkov, A., Schroder, S., AB, E., Codee, J., Overkleeft, H. S., Aerts, H., van Ingen, H., Ubbink, M.. 2019-10-24. Catalysis by a rigid enzyme. https://doi.org/10.1101/815415

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