Figure 1.

ssNMR demonstrates that KcsA channels form clusters in E. coli lipids. A) KcsA clustering can be probed with an equimolar mixture of ¹⁵N‐ and ¹³C‐labeled channels and dedicated ssNMR experiments such as NHHC.9a B) A series of 1D NHHC experiments with increasing ¹H–¹H magnetization transfer times applied to mixed‐labeled channels show the presence of KcsA clusters. C) Cluster formation occurred at low (255 K) and high (293 K) temperature. The lower intensity at 293 K is due to increased local motion, which decreases the dipolar transfer efficiency. D) The virtual absence of signals without ¹³C labeling shows that natural‐abundance contributions can be neglected.