Modulating the Folding Landscape of Superoxide Dismutase 1 with Targeted Molecular Binders

Abstract

Amyotrophic lateral sclerosis,o rL ou Gehrigs disease,i sc haracterized by motor neuron death, with average survival times of two to five years.One cause of this disease is the misfolding of superoxidedismutase 1( SOD1), aphenomenon influenced by point mutations spanning the protein.Herein, we used an epitope-specific high-throughput screen to identify ap eptide ligand that stabilizes the SOD1 native conformation and accelerates its folding by afactor of 2.5. This strategy mayb eu seful for fundamental studies of protein energy landscapes as well as designing new classes of therapeutics. Figure 5. Folding rate constantsfor apo WT SOD1, combinedi nto achevron plot, reveal an enhancement in the folding rate in the presence of ligand by afactor of 2.48, without changing the ratelimiting transition structure (p < 0.005).

Zn-dependent structural transition of SOD1 modulates its ability to undergo liquid-liquid phase separation

“…Both ApoSOD1 2SH and severe mutants (I113TSOD1 2SH and G85RSOD1 2SH ) showed larger rH when compared to G37RSOD1 2SH and WTSOD1 2SH (Supplementary table 1). The value of rH obtained by FCS (this paper) for ApoSOD1 2SH matched well with previous experimental data (34, 35). To obtain further insights into this, we plotted the literature values (47) of rH of different proteins in their compact folded and chemically unfolded states.…”

“…FCS is a correlation analysis of temporal fluctuations of the fluorescence intensity at single molecule level in an approximately femtoliter confocal volume. From the value of the diffusion time (D), we calculated the hydrodynamic radius of ApoSOD1 2SH outside the droplet to be around 2.80 nm, which matched with earlier reports (34,35). Inside the droplets, we observed a large (~2.5 fold) increase in the translational diffusion time (Fig.…”

Antibody-recruiting protein-catalyzed capture agents to combat antibiotic-resistant bacteria

“…60,61 Epitope-targeted PCC ligands against the MrkA protein PCC ligands against the four selected epitopes were identied from a combinatorial library of macrocyclic peptides by using the epitope-targeted PCC method. [42][43][44][45] This method exploits non-catalyzed click chemistry via an in situ click screen. For the screen, an alkyne-presenting, one-bead one-compound (OBOC) combinatorial library of approximately 1 M peptide macrocycles with a 5-residue variable region is screened against synthetic variants of the epitopes (SynEps).…”

“…1). To generate the AR-PCC ligand, we employed the recently reviewed, 41 all synthetic epitope-targeted PCC method, [42][43][44][45] coupled with a bioinformatics approach to identify epitopes for targeting. By targeting highly exposed epitopes of the type 3 Fimbrial Sha (MrkA) surface protein of K. pneumoniae, we developed a small macrocyclic peptide binder in a single generation screen.…”

Stereochemical engineering of a peptide macrocycle allosteric inhibitor of phospho-Akt2 controls cell penetration by fine-tuning macrocycle-cell membrane interactions

“…Ligands have been developed that selectively bind to phosphorylated active protein 18 , proteins with point mutations 19 , or distinguish between two closely related protein isoforms 20 . Cyclic ligands isolated using this technology has also been utilized to allosterically inhibit kinase function 19 , inhibit botulinum toxin uptake in neurons 21 , stabilize the folding of a mutated essential enzyme 22 , and inhibit heme sequestration by Histidine -Rich Protein 2 (HRP2) 23 .…”