4HJS

Kinetic stabilization of transthyretin through covalent modification of K15 by (E)-N-(4-(4-hydroxy-3,5-dimethylstyryl)ethanesulfonamide

Summary for 4HJS

• Entry DOI: 10.2210/pdb4hjs/pdb
• Related: 3HJO 4HJT 4HJU
• Descriptor: Transthyretin, N-{4-[(E)-2-(4-hydroxy-3,5-dimethylphenyl)ethenyl]phenyl}ethanesulfonamide (3 entities in total)
• Functional Keywords: hormone binding protein, thyroxine, retinol binding protein
• Biological source: Homo sapiens (human)
• Cellular location: Secreted: P02766
• Total number of polymer chains: 2
• Total formula weight: 26069.29

Authors

Connelly, S.,Wilson, I.A. (deposition date: 2012-10-14, release date: 2013-12-04, Last modification date: 2023-09-20)

Primary citation

Suh, E.H.,Liu, Y.,Connelly, S.,Genereux, J.C.,Wilson, I.A.,Kelly, J.W.
Stilbene vinyl sulfonamides as fluorogenic sensors of and traceless covalent kinetic stabilizers of transthyretin that prevent amyloidogenesis.
J.Am.Chem.Soc., 135:17869-17880, 2013

PubMed Abstract: Small molecules that react selectively with a specific non-enzyme drug-target protein in a complex biological environment without displacement of a leaving group (tracelessly) are rare and highly desirable. Herein we describe the development of a family of fluorogenic stilbene-based vinyl amides and vinyl sulfonamides that covalently modify transthyretin (TTR) tracelessly. These small molecules bind selectively to TTR in complex biological environments and then undergo a rapid and chemoselective 1,4-Michael addition with the pKa-perturbed Lys-15 ε-amino group of TTR. Replacing the vinyl amide in 2 with the more reactive vinyl sulfonamide in 4 hastens the conjugation kinetics. X-ray cocrystallography verified the formation of the secondary amine bond mediating the conjugation in the case of 2 and 4 and confirmed the expected orientation of the stilbene within the TTR binding sites. Vinyl amide 2 and vinyl sulfonamide 4 potently inhibit TTR dissociation and amyloid fibril formation in vitro. The TTR binding selectivity, modification yield, and reaction chemoselectivity of vinyl sulfonamide 4 are good enough in human plasma to serve as a starting point for medicinal chemistry efforts. Moreover, vinyl sulfonamide 4 is fluorogenic: it exhibits minimal background fluorescence in complex biological environments, remains dark upon binding to TTR, and becomes fluorescent only upon reaction with TTR. The fluorogenicity of 4 was utilized to accurately quantify the native TTR concentration in Escherichia coli lysate using a fluorescence plate reader.

PubMed: 24180271
DOI: 10.1021/ja408230k

Experimental method

X-RAY DIFFRACTION (1.22 Å)