{"id":{"repo_id":"strathclyde","oai_identifier":"oai:strathclyde:h128nd689"},"canonical_url":"https://search.dev.ndltd.org/etd/strathclyde/oai:strathclyde:h128nd689","repository":{"repo_id":"strathclyde","name":"University of Strathclyde","base_url":"https://stax.strath.ac.uk/catalog/oai"},"display":{"title":"Design and synthesis of molecular tools for the ubiquitin proteasome system","abstract":"Alzheimer's disease (AD) has become one of the biggest global public health challenges, with 0.5% of the population living with dementia. The ubiquitin proteasome system (UPS), in particular the interaction between a mutant form of ubiquitin, Ubb+1, and the E2-conjugating enzyme E2-25K, has been identified as playing a possible pathophysiological role in the early and late stage progression of AD. The E2-25K/Ubb+1 protein-protein interaction (PPI) is regulated by the α-helix 9 of E2-25K. Creating a short helical peptide analogous to α-9 of E2-25K with the technique of peptide stapling could potentially block the action of Ubb+1 and provide a tool to investigate the role of the UPS in AD.Following synthesis of the requisite alkenyl amino acids for peptide stapling, an initial palette of nine peptides, containing the wild-type E2-25K sequence, and eight stapled analogues, were successfully synthesized and ring-closed on the solid phase. Circular dichroism spectroscopy was used to analyse secondary structure, revealing the peptides exhibited a range of 16 - 91% helicity. Further NMR studies demonstrated the more precise helical nature of short helical peptides in solution. Preliminary biological assays indicated that the synthesised peptides are capable of inhibiting Ubb+1 incorporation into long polyubiquitin chains. Remarkably, these antagonists proved to be selective towards Ubb+1 over ubiquitin despite the high degree of similarity in the relative binding sites of the two proteins. Further in silico design led to the development of a second generation of six stapled peptides. Further biological evaluation revealed an additional sequence potentially capable of activating E2-25K mediated Ubb+1 capped PolyUb chain formation.Overall, this preliminary study has shown that short helical analogues of E2-25K can be successfully synthesized and used to block or activate the E2-25K/Ubb+1 PPI. Further optimisation of these stapled peptides could provide valuable tool compounds into the investigation of Ubb+1 mediated inhibition of the UPS, and the downstream effects on the pathogenesis of AD.","abstract_html":"Alzheimer's disease (AD) has become one of the biggest global public health challenges, with 0.5% of the population living with dementia. The ubiquitin proteasome system (UPS), in particular the interaction between a mutant form of ubiquitin, Ubb+1, and the E2-conjugating enzyme E2-25K, has been identified as playing a possible pathophysiological role in the early and late stage progression of AD. The E2-25K/Ubb+1 protein-protein interaction (PPI) is regulated by the α-helix 9 of E2-25K. Creating a short helical peptide analogous to α-9 of E2-25K with the technique of peptide stapling could potentially block the action of Ubb+1 and provide a tool to investigate the role of the UPS in AD.Following synthesis of the requisite alkenyl amino acids for peptide stapling, an initial palette of nine peptides, containing the wild-type E2-25K sequence, and eight stapled analogues, were successfully synthesized and ring-closed on the solid phase. Circular dichroism spectroscopy was used to analyse secondary structure, revealing the peptides exhibited a range of 16 - 91% helicity. Further NMR studies demonstrated the more precise helical nature of short helical peptides in solution. Preliminary biological assays indicated that the synthesised peptides are capable of inhibiting Ubb+1 incorporation into long polyubiquitin chains. Remarkably, these antagonists proved to be selective towards Ubb+1 over ubiquitin despite the high degree of similarity in the relative binding sites of the two proteins. Further in silico design led to the development of a second generation of six stapled peptides. Further biological evaluation revealed an additional sequence potentially capable of activating E2-25K mediated Ubb+1 capped PolyUb chain formation.Overall, this preliminary study has shown that short helical analogues of E2-25K can be successfully synthesized and used to block or activate the E2-25K/Ubb+1 PPI. Further optimisation of these stapled peptides could provide valuable tool compounds into the investigation of Ubb+1 mediated inhibition of the UPS, and the downstream effects on the pathogenesis of AD.","abstract_has_math":false,"creators":["Watson, Morag Elspeth"],"institution":"University of Strathclyde","degree_name":"phd","degree_level":"doctoral-pg","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016","date_published":"2016","updated_at":"2026-07-24T04:41:44Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier.doi","label":"DOI","values":["10.48730/gvke-s625"],"render_values":[{"text":"10.48730/gvke-s625","href":"https://doi.org/10.48730/gvke-s625","code":true}]},{"key":"dc:identifier","label":"Identifier","values":["T14420"],"render_values":[{"text":"T14420","href":null,"code":true}]},{"key":"dc:creator.authoridentifier","label":"Author Identifier","values":["201286014"],"render_values":[{"text":"201286014","href":null,"code":true}]}]},"links":{"outbound_url":"https://stax.strath.ac.uk/concern/theses/h128nd689","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Watson, Morag Elspeth"]},{"key":"dc:creator.authoridentifier","label":"Author Identifier","values":["201286014"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2016"]},{"key":"dc:date.issued","label":"Date","values":["2016"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Pure and Applied Chemistry"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Strathclyde"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["doctoral-pg"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["phd"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["T14420"]},{"key":"dc:identifier.doi","label":"DOI","values":["10.48730/gvke-s625"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://stax.strath.ac.uk/concern/theses/h128nd689"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Alzheimer's disease (AD) has become one of the biggest global public health challenges, with 0.5% of the population living with dementia. The ubiquitin proteasome system (UPS), in particular the interaction between a mutant form of ubiquitin, Ubb+1, and the E2-conjugating enzyme E2-25K, has been identified as playing a possible pathophysiological role in the early and late stage progression of AD. The E2-25K/Ubb+1 protein-protein interaction (PPI) is regulated by the α-helix 9 of E2-25K. Creating a short helical peptide analogous to α-9 of E2-25K with the technique of peptide stapling could potentially block the action of Ubb+1 and provide a tool to investigate the role of the UPS in AD.Following synthesis of the requisite alkenyl amino acids for peptide stapling, an initial palette of nine peptides, containing the wild-type E2-25K sequence, and eight stapled analogues, were successfully synthesized and ring-closed on the solid phase. Circular dichroism spectroscopy was used to analyse secondary structure, revealing the peptides exhibited a range of 16 - 91% helicity. Further NMR studies demonstrated the more precise helical nature of short helical peptides in solution. Preliminary biological assays indicated that the synthesised peptides are capable of inhibiting Ubb+1 incorporation into long polyubiquitin chains. Remarkably, these antagonists proved to be selective towards Ubb+1 over ubiquitin despite the high degree of similarity in the relative binding sites of the two proteins. Further in silico design led to the development of a second generation of six stapled peptides. Further biological evaluation revealed an additional sequence potentially capable of activating E2-25K mediated Ubb+1 capped PolyUb chain formation.Overall, this preliminary study has shown that short helical analogues of E2-25K can be successfully synthesized and used to block or activate the E2-25K/Ubb+1 PPI. Further optimisation of these stapled peptides could provide valuable tool compounds into the investigation of Ubb+1 mediated inhibition of the UPS, and the downstream effects on the pathogenesis of AD."]},{"key":"dc:description.abstract","label":"Abstract","values":["Alzheimer's disease (AD) has become one of the biggest global public health challenges, with 0.5% of the population living with dementia. The ubiquitin proteasome system (UPS), in particular the interaction between a mutant form of ubiquitin, Ubb+1, and the E2-conjugating enzyme E2-25K, has been identified as playing a possible pathophysiological role in the early and late stage progression of AD. The E2-25K/Ubb+1 protein-protein interaction (PPI) is regulated by the α-helix 9 of E2-25K. Creating a short helical peptide analogous to α-9 of E2-25K with the technique of peptide stapling could potentially block the action of Ubb+1 and provide a tool to investigate the role of the UPS in AD.Following synthesis of the requisite alkenyl amino acids for peptide stapling, an initial palette of nine peptides, containing the wild-type E2-25K sequence, and eight stapled analogues, were successfully synthesized and ring-closed on the solid phase. Circular dichroism spectroscopy was used to analyse secondary structure, revealing the peptides exhibited a range of 16 - 91% helicity. Further NMR studies demonstrated the more precise helical nature of short helical peptides in solution. Preliminary biological assays indicated that the synthesised peptides are capable of inhibiting Ubb+1 incorporation into long polyubiquitin chains. Remarkably, these antagonists proved to be selective towards Ubb+1 over ubiquitin despite the high degree of similarity in the relative binding sites of the two proteins. Further in silico design led to the development of a second generation of six stapled peptides. Further biological evaluation revealed an additional sequence potentially capable of activating E2-25K mediated Ubb+1 capped PolyUb chain formation.Overall, this preliminary study has shown that short helical analogues of E2-25K can be successfully synthesized and used to block or activate the E2-25K/Ubb+1 PPI. Further optimisation of these stapled peptides could provide valuable tool compounds into the investigation of Ubb+1 mediated inhibition of the UPS, and the downstream effects on the pathogenesis of AD."]},{"key":"dc:title","label":"Title","values":["Design and synthesis of molecular tools for the ubiquitin proteasome system"]}]}],"canonical_facts":{"dc:creator":["Watson, Morag Elspeth"],"dc:creator.authoridentifier":["201286014"],"dc:date":["2016"],"dc:date.issued":["2016"],"dc:description":["Alzheimer's disease (AD) has become one of the biggest global public health challenges, with 0.5% of the population living with dementia. The ubiquitin proteasome system (UPS), in particular the interaction between a mutant form of ubiquitin, Ubb+1, and the E2-conjugating enzyme E2-25K, has been identified as playing a possible pathophysiological role in the early and late stage progression of AD. The E2-25K/Ubb+1 protein-protein interaction (PPI) is regulated by the α-helix 9 of E2-25K. Creating a short helical peptide analogous to α-9 of E2-25K with the technique of peptide stapling could potentially block the action of Ubb+1 and provide a tool to investigate the role of the UPS in AD.Following synthesis of the requisite alkenyl amino acids for peptide stapling, an initial palette of nine peptides, containing the wild-type E2-25K sequence, and eight stapled analogues, were successfully synthesized and ring-closed on the solid phase. Circular dichroism spectroscopy was used to analyse secondary structure, revealing the peptides exhibited a range of 16 - 91% helicity. Further NMR studies demonstrated the more precise helical nature of short helical peptides in solution. Preliminary biological assays indicated that the synthesised peptides are capable of inhibiting Ubb+1 incorporation into long polyubiquitin chains. Remarkably, these antagonists proved to be selective towards Ubb+1 over ubiquitin despite the high degree of similarity in the relative binding sites of the two proteins. Further in silico design led to the development of a second generation of six stapled peptides. Further biological evaluation revealed an additional sequence potentially capable of activating E2-25K mediated Ubb+1 capped PolyUb chain formation.Overall, this preliminary study has shown that short helical analogues of E2-25K can be successfully synthesized and used to block or activate the E2-25K/Ubb+1 PPI. Further optimisation of these stapled peptides could provide valuable tool compounds into the investigation of Ubb+1 mediated inhibition of the UPS, and the downstream effects on the pathogenesis of AD."],"dc:description.abstract":["Alzheimer's disease (AD) has become one of the biggest global public health challenges, with 0.5% of the population living with dementia. The ubiquitin proteasome system (UPS), in particular the interaction between a mutant form of ubiquitin, Ubb+1, and the E2-conjugating enzyme E2-25K, has been identified as playing a possible pathophysiological role in the early and late stage progression of AD. The E2-25K/Ubb+1 protein-protein interaction (PPI) is regulated by the α-helix 9 of E2-25K. Creating a short helical peptide analogous to α-9 of E2-25K with the technique of peptide stapling could potentially block the action of Ubb+1 and provide a tool to investigate the role of the UPS in AD.Following synthesis of the requisite alkenyl amino acids for peptide stapling, an initial palette of nine peptides, containing the wild-type E2-25K sequence, and eight stapled analogues, were successfully synthesized and ring-closed on the solid phase. Circular dichroism spectroscopy was used to analyse secondary structure, revealing the peptides exhibited a range of 16 - 91% helicity. Further NMR studies demonstrated the more precise helical nature of short helical peptides in solution. Preliminary biological assays indicated that the synthesised peptides are capable of inhibiting Ubb+1 incorporation into long polyubiquitin chains. Remarkably, these antagonists proved to be selective towards Ubb+1 over ubiquitin despite the high degree of similarity in the relative binding sites of the two proteins. Further in silico design led to the development of a second generation of six stapled peptides. Further biological evaluation revealed an additional sequence potentially capable of activating E2-25K mediated Ubb+1 capped PolyUb chain formation.Overall, this preliminary study has shown that short helical analogues of E2-25K can be successfully synthesized and used to block or activate the E2-25K/Ubb+1 PPI. Further optimisation of these stapled peptides could provide valuable tool compounds into the investigation of Ubb+1 mediated inhibition of the UPS, and the downstream effects on the pathogenesis of AD."],"dc:identifier":["T14420"],"dc:identifier.doi":["10.48730/gvke-s625"],"dc:identifier.uri":["https://stax.strath.ac.uk/concern/theses/h128nd689"],"dc:publisher.department":["Department of Pure and Applied Chemistry"],"dc:publisher.institution":["University of Strathclyde"],"dc:title":["Design and synthesis of molecular tools for the ubiquitin proteasome system"],"dc:type.qualificationlevel":["doctoral-pg"],"dc:type.qualificationname":["phd"]},"updated_at":"2026-07-24T04:41:44Z"}