Cucurbit[7]uril Enhances Distance Measurements of Spin-Labeled Proteins.

ABSTRACT: We report complex formation between the chloroacetamide 2,6-diazaadamantane nitroxide radical (ClA-DZD) and cucurbit[7]uril (CB-7), for which the association constant in water, K_a = 1.9 × 10⁶ M^-1, is at least one order of magnitude higher than the previously studied organic radicals. The radical is highly immobilized by CB-7, as indicated by the increase of the rotational correlation time, τ_rot, by a factor of 36, relative to that in the buffer solution. The X-ray structure of ClA-DZD@CB-7 shows the encapsulated DZD guest inside the undistorted CB-7 host, with the pendant group protruding outside. Upon addition of CB-7 to T4 Lysozyme (T4L) doubly spin-labeled with the iodoacetamide derivative of DZD, we observe the increase in τ<

SUBMITTER: Yang Z 

PROVIDER: S-EPMC10473685 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature