Change search
ReferencesLink to record
Permanent link

Direct link
Application of gel-phase 19F NMR spectroscopy for optimization of solid-phase synthesis of a hydrophobic peptide from the signal sequence of the mucin MUC1
Umeå University, Faculty of Science and Technology, Chemistry.
Umeå University, Faculty of Science and Technology, Chemistry.
Umeå University, Faculty of Science and Technology, Chemistry.
2007 (English)In: Journal of Peptide Science, ISSN 1075-2617, Vol. 13, no 5, 354-361 p.Article in journal (Refereed) Published
Abstract [en]

This paper describes the manual Fmoc/t-Bu solid-phase synthesis of a difficult nine-residue hydrophobic peptide LLLLTVLTV from one of the signal sequences that flank the tandem repeat of the mucin MUC1. Gel-phase 19F NMR spectroscopy was used as a straightforward method for optimization of the solid-phase synthesis. Different approaches were applied for comparative studies. The strategy based on modified solid-phase conditions using DIC/HOAt for coupling, DBU for Fmoc deprotection, and the incorporation of the pseudo proline dipeptide Fmoc-Leu-Thr(Me, Me pro)-OH as a backbone-protecting group was found to be superior according to gel-phase 19F NMR spectroscopy. Implementation of the optimized Fmoc protocol enabled an effective synthesis of signal peptide LLLLTVLTV.

Place, publisher, year, edition, pages
2007. Vol. 13, no 5, 354-361 p.
Keyword [en]
solid-phase peptide synthesis, difficult sequence, gel-phase 19F NMR, pseudo proline
URN: urn:nbn:se:umu:diva-12721DOI: doi:10.1002/psc.850OAI: diva2:152392
Available from: 2008-05-19 Created: 2008-05-19Bibliographically approved
In thesis
1. Antigens derived from the mucin MUC1: Solution and solid-phase synthesis of saccharides, peptides and glycopeptides
Open this publication in new window or tab >>Antigens derived from the mucin MUC1: Solution and solid-phase synthesis of saccharides, peptides and glycopeptides
2008 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Mucin is a term used to describe a large family of heavily glycosylated proteins which are present on the surfaces of secretory epithelial cells and are overexpressed by many carcinomas. Membrane-bound mucin MUC1 is of special interest. Its backbone consists of repeating units of twenty amino acids with five potential glycosylation sites. These sites are expanded to structures like the T (Galβ(1->3)GalNA-Ser/Thr) and Tn (GalNA-Ser/Thr) antigens by the action of various glycosyltransferases. In different types of carcinomas these epitopes are being terminated by sialic acid residues to form among others: 2,3-sialyl-T and sialyl-Tn structures due to the elevated levels of different sialyltransferases.

Solid-phase synthesis of the selected antigens derived from the mucin MUC1 has been developed and optimized. A chemoenzymatic approach has been used to effectively prepare 2,3-sialyl-T and 2,6-sialyl-Tn glycopeptides. The formation of intramolecular sialic acid lactones in presence of acetic acid was investigated. The stability of lactones formed from 2,3-sialyl-T towards water was studied using NMR spectroscopy and it appeared that 1''->2' lactone displayed remarkable strength to hydrolysis and it was suggested as a candidate for cancer vaccine.

Gel-phase 19F NMR spectroscopy is known to be a very good tool to characterize resin-bound products using fluorinated protecting groups and linker molecules. The hydrophobic peptide LLLLTVLTV, which is a fragment from the MUC1 signal sequence, was prepared using solid-phase synthesis according to a modified Fmoc protocol with more active coupling reagent, stronger base, and the isopropylidene dipeptide Fmoc-Leu-Thr-(ΨMe,Mepro)-OH. Gel-phase 19F NMR spectroscopy was used to evaluate peptide chain aggregation and coupling and deprotection efficiency.

A carbamate linker strategy proved to be effective in solid-phase synthesis of serine-based neoglycolipids with terminal amino functionality. Neoglycolipids were covalently bound to secondary amines in microtiter plates using squaric acid ester methodology. These arrays have potential to study the interactions between carbohydrates and e.g. proteins and microbes.

The new fluorinated α-amino protective group [1-(4-(4-fluorophenyl)-2,6-dioxocyclohexylidene)ethyl] Fde was developed. This group is cleaved with hydrazine in DMF solution. By using amino acids protected with this group, it was possible to quantify the efficiency of peptide coupling using gel-phase 19F NMR spectroscopy.

Place, publisher, year, edition, pages
Umeå: Kemi, 2008. 76 p.
Lactones, glycopeptides, signal peptide, neoglycolipid arrays, solid-phase synthesis, MUC1, gel-phase 19F NMR spectroscopy, fluorinated alpha-amino protective group
National Category
Organic Chemistry
urn:nbn:se:umu:diva-1630 (URN)978-91-7264-557-8 (ISBN)
Public defence
2008-05-24, KB3B1, Stora Hörsalen, KBC, Linneaus v., Umeå, 10:00 (English)
Available from: 2008-04-29 Created: 2008-04-29 Last updated: 2010-01-21Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Pudelko, MaciejKihlberg, JanElofsson, Mikael
By organisation
In the same journal
Journal of Peptide Science

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 52 hits
ReferencesLink to record
Permanent link

Direct link