Electrostatic peptide-lipid interactions of amyloid-β peptide and pentalysine with membrane surfaces monitored by 31P MAS NMR
2001 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, Vol. 3, no 14, 2904-2910 p.Article in journal (Refereed) Published
High-resolution 31P magic angle spinning (MAS) NMR spectroscopy is presented as a direct and non-perturbing method for measuring changes in surface charge density occurring in mixed phospholipid membranes upon binding of charged surface-active peptides. 31P MAS NMR was used to investigate mixed lipid membranes of neutral phosphatidylcholine and negatively charged phosphatidylglycerol where the molar fraction of the charged lipid was varied from 0 to 1. The chemical shifts of the individual membrane lipids showed a simple variation in response to changes in the fraction of the negatively charged component phosphatidylglycerol. Addition of the positively charged amyloid-β1-40 peptide, a key substance in Alzheimer's disease, resulted in changes in the isotropic chemical shifts of the membrane lipid phosphates in a way consistent with reduction in the negative surface charge of the mixed lipid bilayers. Binding of different amounts of the positively charged peptide pentalysine to L-α-dioleoylphosphatidylcholine/L-α-dioleoylphosphatidylglycerol(DOPC/DOPG) vesicles (2 : 1 molar ratio) also showed a systematic variation of both chemical shift values. These changes were described by a simple two-site model and indicate purely electrostatic binding of pentalysine.
Place, publisher, year, edition, pages
2001. Vol. 3, no 14, 2904-2910 p.
IdentifiersURN: urn:nbn:se:umu:diva-5646DOI: 10.1039/b103352mOAI: oai:DiVA.org:umu-5646DiVA: diva2:145231