eprintid: 35861 rev_number: 10 userid: 7556 dir: disk0/00/03/58/61 datestamp: 2019-01-30 23:55:51 lastmod: 2019-01-30 23:55:51 status_changed: 2019-01-30 23:55:51 type: thesis_degree succeeds: 33872 metadata_visibility: show contact_email: alypson@gmail.com item_issues_id: thesis_degree_versioning item_issues_type: thesis_degree_versioning item_issues_description: ETD 35861 is using versioning. item_issues_timestamp: 2019-01-08 07:01:58 item_issues_status: discovered item_issues_count: 1 eprint_status: archive creators_name: Lypson, Alyssa creators_email: abl25@pitt.edu creators_id: abl25 creators_orcid: 0000-0003-3687-1839 title: Engineering a β–Turn Mimetic Torsion Balance For Conformational Control: Design, Synthetic Strategies and NMR Analysis ispublished: unpub divisions: sch_as_chemistry full_text_status: public keywords: torsion balance, peptidomimetics, protein folding, β–turn mimic, conformational control, conformational constrain, molecular scaffolds, molecular design, synthesis, NMR, solid-phase synthesis, SPPS abstract: The molecular torsion balance concept was applied to a peptide-hybrid balance to accurately investigate the effects of amino acid changes on antiparallel β-sheet configuration and stability for applications in molecular recognition and computational drug design. In this study, we report an engineered design of that balance for improved interchain alignment by introduction of noncovalent steric constraint at the reverse turn. Our design utilizes a restricted N-aryl bond rotation to impose a two-state folded model by incorporating an (ortho-tolyl)amide into a locked biaryl system. The turn mimetic nucleates hairpin formation in an antiparallel β-sheet configuration upon attachment of peptide sequences, providing a minimal model system to investigate biologically interesting epitopes. Bromine installation ortho to peptide chain attachment sites imposed an additional degree of conformational control for improved thermodynamic stability in the folded conformation. Our design approach, which relied upon Monte Carlo simulations of substituted native chorismate pyruvate lyase (CPL75-93), is described along with solution-phase and solid-phase synthetic strategies. 1H and 2D NMR experiments revealed improved interchain alignment to promote hydrogen bond formation in the conformationally controlled synthetic peptidomimetic torsion balance hybrid compared to a control molecule. Line shape analysis of low temperature 1H NMR data approximated rotational restriction around the aryl ether bond to be 11 kcal/mol at 193 K in CD2Cl2. 1H NMR AND 2D ROESY analyses reveal an improved shape to mimic the ends of an antiparallel β-sheet. Hydrogen bond formation has been identified between NH amide proton of the upper side chain (proton donor) and glycine acetamide of the lower side chain (proton donor) and glycine acetamide of the lower side chain (proton acceptor). Results confirm bromine substituents impose noncovalent steric constraints ortho to the peptide side chains to reduce conformational entropy of the upper peptide chains. date: 2019-01-30 date_type: published pages: 276 institution: University of Pittsburgh refereed: TRUE etdcommittee_type: committee_chair etdcommittee_type: committee_member etdcommittee_type: committee_member etdcommittee_type: committee_member etdcommittee_name: Wilcox, Craig S. etdcommittee_name: Curran, Dennis P. etdcommittee_name: Gold, Barry etdcommittee_name: Horne, W. Seth etdcommittee_email: daylite@pitt.edu etdcommittee_email: curran@pitt.edu etdcommittee_email: goldbi@pitt.edu etdcommittee_email: horne@pitt.edu etdcommittee_id: daylite etdcommittee_id: curran etdcommittee_id: goldbi etdcommittee_id: horne etdcommittee_orcid: 0000-0001-9644-7728 etdcommittee_orcid: 0000-0002-2610-978X etdcommittee_orcid: 0000-0003-2927-1739 etd_defense_date: 2018-10-30 etd_approval_date: 2019-01-30 etd_submission_date: 2018-12-04 etd_release_date: 2019-01-30 etd_access_restriction: immediate etd_patent_pending: FALSE thesis_type: dissertation degree: PhD citation: Lypson, Alyssa (2019) Engineering a β–Turn Mimetic Torsion Balance For Conformational Control: Design, Synthetic Strategies and NMR Analysis. Doctoral Dissertation, University of Pittsburgh. (Unpublished) document_url: http://d-scholarship-dev.library.pitt.edu/35861/13/Lypson_PhD_ETD_final.pdf