CHEMICAL APPROACHES TO IMPROVE THE MANUFACTURABILITY OF DISULFIDE-RICH PEPTIDE TOXINS – ENGINEERING A STABLE AND SELECTIVE PEPTIDE BLOCKER OF THE KCa1.1 CHANNEL
CHEMICAL APPROACHES TO IMPROVE THE MANUFACTURABILITY OF DISULFIDE-RICH PEPTIDE TOXINS – ENGINEERING A STABLE AND SELECTIVE PEPTIDE BLOCKER OF THE KCa1.1 CHANNEL
Date
2022
Authors
Delgado, Erick Medermel
Contributor
Advisor
Bingham, Jon-Paul
Department
Biological Engineering
Instructor
Depositor
Speaker
Researcher
Consultant
Interviewer
Annotator
Journal Title
Journal ISSN
Volume Title
Publisher
Volume
Number/Issue
Starting Page
Ending Page
Alternative Title
Abstract
Scorpion venoms represent an immense source of bioactive peptides which are potent and selective effectors of sodium (Na+), potassium (K+), chloride (Cl-), and calcium (Ca2+) ion channels. Many of these compounds boast premium advantages which qualify them as attractive molecular tools and pharmaceutical leads: they penetrate tissue effectively while mitigating off-target toxicity, are capable of selectively binding specific ion channel subtypes, alter channel function in a variety of desired ways: inhibit, potentiate, change the kinetics, etc. Unfortunately, many scorpion venom peptides feature unstable functional groups, are prone to aggregation during synthesis or oxidation, and require specific disulfide connectivity, all of which can complicate manufacturing and ultimately reduce synthetic yield. Using solid-phase peptide synthesis, native chemical ligation (NCL), and orthogonal bioconjugation, an effective bioengineering approach was developed for a stable and selective peptide blocker of the KCa1.1, calcium-activated potassium channel. This novel 37 amino acid Iberiotoxin (IbTX) analog, azido-IbTX-W14F, incorporates a mid-sequence Val16Ala mutation to facilitate thioester mediated NCL, homologous substitutions of oxidation prone Met29 and Tyr14 residues, and an orthogonally conjugated azido-Lys19 residue capable of fluorescent bioconjugation with a phosphine fluorophore. Azido-IbTX-W14F retained native-like bioactivity according to electrophysiology studies, exhibited increased solution stability, and was demonstrated to be amenable to chemoselective fluorescent bioconjugation. The resulting fluorescent-IbTX analog has potential as a diagnostic tool or as a drug lead for disease states mediated by KCa1.1.
Description
Keywords
Bioengineering
Citation
Extent
71 pages
Format
Geographic Location
Time Period
Related To
Table of Contents
Rights
All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
Rights Holder
Local Contexts
Collections
Email libraryada-l@lists.hawaii.edu if you need this content in ADA-compliant format.