Ligand-Induced Stabilization of the Native Human Superoxide Dismutase 1

Abstract

A common characteristic of familial (fALS) and sporadic amyotrophic lateral sclerosis (sALS) is the accumulation of aberrant proteinaceous species in the motor neurons and spinal cord of ALS patientsincluding aggregates of the human superoxide dismutase 1 (hSOD1). hSOD1 is an enzyme that occurs as a stable dimeric protein with several post-translational modifications such as the formation of an intramolecular disulfide bond and the acquisition of metal cofactors that are essential for enzyme activity and further contribute to protein stability. Some mutations and/or destabilizing factors promote hSOD1 misfolding, causing neuronal death. Aggregates containing misfolded wild-type hSOD1 have been found in the spinal cords of sALS as well as in non-hSOD1 fALS patients, leading to the hypothesis that hSOD1 misfolding is a common part of the ALS pathomechanism. Therefore, stabilizing the native conformation of SOD1 may be a promising approach to prevent the formation of toxic hSOD1 species and thus ALS pathogenesis. Here, we present the 16-mer peptide S1VL-21 that interferes with hSOD1 aggregation. S1VL-21 was identified by phage display selection with the native conformation of hSOD1 as a target. Several methods such as microscale thermophoresis (MST) measurements, aggregation assays, and cell viability assays revealed that S1VL-21 has a micromolar binding affinity to native hSOD1 and considerably reduces the formation of hSOD1 aggregates. This present work therefore provides the first important data on a potential lead compound for hSOD1-related drug development for ALS therapy.

Phage Display-Derived Compounds Displace hACE2 from Its Complex with SARS-CoV-2 Spike Protein

“…Variable DNA sequences resulting from next generation sequencing (NGS) were transcribed into peptide sequences, as described previously [ 36 ]. The transcribed sequences were filtered based on their relative frequency increase within the TS (library < TS1 < TS2 < TS3), the relative frequency of a sequence observed in one TS compared to its abundancy within the respective DC (TS2 > DC2; TS3 > DC3) and the relative frequency of one sequence observed in one TS round compared to its abundancy within the respective ES round (TS1 > ES1; TS2 > ES2; TS3 > ES3).…”

Inhibition of Polyglutamine Misfolding with D-Enantiomeric Peptides Identified by Mirror Image Phage Display Selection

“…The selected phages from the phage library presenting 16mer peptides on their surface were analyzed via Next Generation Sequencing (NGS). The sequencing data were evaluated via TSAT, evaluation software developed by our work group [ 42 ] and the clustering tool Hammock [ 43 ]. There was no general sequence alignment of all selected sequences possible.…”

“…The single-stranded phage DNA was prepared for analysis by next generation sequencing (NGS) as described previously [ 42 ].…”

“…The data evaluation was performed with the software Target Sequencing Analysis Tool (TSAT) and Hammock [ 43 ], as described previously [ 42 ].…”

Discovery of all-D-peptide inhibitors of SARS CoV 2 3C-like protease

“…Besides the primary selection with 3CL pro as the target (Target Selection, TS), two control selections were performed as described before 40 diluted in washing buffer to a final concentration of 0.35 ng/µL, and 100 µL was added to each well for 1 h at RT. After 6 washing steps with 150 µL washing buffer, the supernatant was removed entirely, and 100 µL of the 3,3',5,5'-tetramethylbenzidine (TMB) solution (TMB was previously dissolved in 1 mL DMSO and diluted with 9 mL 0.05 M phosphate citrate buffer pH 5) were added into each well.…”