PDBsum entry 5ekm

Lyase/lyase inhibitor

PDB id: 5ekm

Contents

Protein chain

257 a.a.

Ligands

GOL

TG5

Metals

_ZN

_NA

Waters ×231

References listed in PDB file

Key reference

• Title: Programming a molecular relay for ultrasensitive biodetection through (129)xe nmr.
• Authors: Y.Wang, B.W.Roose, J.P.Philbin, J.L.Doman, I.J.Dmochowski.
• Ref.: Angew Chem Int Ed Engl, 2016, 55, 1733-1736. [DOI no: 10.1002/anie.201508990]
• PubMed id: 26692420

Note: In the PDB file this reference is annotated as "TO BE PUBLISHED". The citation details given above have been manually determined.

Abstract

A supramolecular strategy for detecting specific proteins in complex media by using hyperpolarized (129) Xe NMR is reported. A cucurbit[6]uril (CB[6])-based molecular relay was programmed for three sequential equilibrium conditions by designing a two-faced guest (TFG) that initially binds CB[6] and blocks the CB[6]-Xe interaction. The protein analyte recruits the TFG and frees CB[6] for Xe binding. TFGs containing CB[6]- and carbonic anhydrase II (CAII)-binding domains were synthesized in one or two steps. X-ray crystallography confirmed TFG binding to Zn(2+) in the deep CAII active-site cleft, which precludes simultaneous CB[6] binding. The molecular relay was reprogrammed to detect avidin by using a different TFG. Finally, Xe binding by CB[6] was detected in buffer and in E. coli cultures expressing CAII through ultrasensitive (129) Xe NMR spectroscopy.