Membrane‐protein structure determination by solid‐state NMR spectroscopy of microcrystals: The autotransport domain of Yersinia YadA

Abstract

Membrane proteins are largely underrepresented among available atomic‐resolution structures. The use of detergents in protein purification procedures hinders the formation of well‐ordered crystals for X‐ray crystallography and leads to slower molecular tumbling, impeding the application of solution‐state NMR. Solid‐state magic‐angle spinning NMR spectroscopy is an emerging method for membrane‐protein structural biology that can overcome these technical problems. Here we present the solid‐state NMR structure of the transmembrane domain of the Yersinia enterocolitica adhesin A (YadA). The sample was derived from crystallization trials that yielded only poorly diffracting microcrystals.We solved the structure using a single, uniformly 13C‐ and 15N‐labeled sample. In addition, solid‐state NMR allowed us to acquire information on the flexibility and mobility of parts of the structure, which, in combination with evolutionary conservation information, presents new insights into the autotransport mechanism of YadA.Funding: This work was supported by contract research ‘Forschungsprogramm Methoden für die Lebenswissenschaften’ of the Baden‐Württemberg Stiftung