PDBsum entry 6xxc

Peptide binding protein

PDB id: 6xxc

Contents

Protein chain

235 a.a.

Ligands

ARG-ARG-ARG-LYS-SEP-CYS-GLN

O3W

Metals

_MG ×3

_CL

Waters ×346

PDB id:

6xxc

Name:

Peptide binding protein

Title:

Ternary complex of 14-3-3 sigma (c38n), estrogen related receptor gamma (dbd) phosphopeptide, and disulfide ppi stabilizer 4

Structure:

14-3-3 protein sigma. Chain: a. Synonym: epithelial cell marker protein 1,stratifin. Engineered: yes. Mutation: yes. Estrogen related receptor gamma phosphopeptide. Chain: b. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: sfn, hme1. Expressed in: escherichia coli. Expression_system_taxid: 562. Synthetic: yes. Organism_taxid: 9606

Resolution:

1.30Å R-factor: 0.165 R-free: 0.181

Authors:

B.A.Somsen,C.Ottmann

Key ref:

E.Sijbesma et al. (2020). Fluorescence Anisotropy-Based Tethering for Discovery of Protein-Protein Interaction Stabilizers. ACS Chem Biol, 15, 3143-3148. PubMed id: 33196173 DOI: 10.1021/acschembio.0c00646

Date:

27-Jan-20 Release date: 18-Nov-20

Protein chain

P31947  (1433S_HUMAN) -  14-3-3 protein sigma from Homo sapiens

Seq: 248 a.a.

Struc: 235 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1021/acschembio.0c00646

ACS Chem Biol 15:3143-3148 (2020)

PubMed id: 33196173

Fluorescence Anisotropy-Based Tethering for Discovery of Protein-Protein Interaction Stabilizers.

E.Sijbesma, B.A.Somsen, G.P.Miley, I.A.Leijten-van de Gevel, L.Brunsveld, M.R.Arkin, C.Ottmann.

ABSTRACT

Protein-protein interaction (PPI) networks are fundamental for cellular processes. Small-molecule PPI enhancers have been shown to be powerful tools to fundamentally study PPIs and as starting points for potential new therapeutics. Yet, systematic approaches for their discovery are not widely available, and the design prerequisites of "molecular glues" are poorly understood. Covalent fragment-based screening can identify chemical starting points for these enhancers at specific sites in PPI interfaces. We recently reported a mass spectrometry-based disulfide-trapping (tethering) approach for a cysteine residue in the hub protein 14-3-3, an important regulator of phosphorylated client proteins. Here, we invert the strategy and report the development of a functional read-out for systematic identification of PPI enhancers based on fluorescence anisotropy (FA-tethering) with the reactive handle now on a client-derived peptide. Using the DNA-binding domain of the nuclear receptor Estrogen Related Receptor gamma (ERRγ), we target a native cysteine positioned at the 14-3-3 PPI interface and identify several fragments that form a disulfide bond to ERRγ and stabilize the complex up to 5-fold. Crystallography indicates that fragments bind in a pocket comprised of 14-3-3 and the ERRγ phosphopeptide. FA-tethering presents a streamlined methodology to discover molecular glues for protein complexes.