Interaction with model phospholipid membranes of lupin seed γ-conglutin, a glycaemia-lowering protein from Lupinus albus seeds, has been studied by means of Fourier-Transform infrared spectroscopy at p2H 7.0 and at p2H 4.5. The protein maintains the same secondary structure both at p2H 7.0 and at p2H 4.5, but at p2H 7.0 a higher 1H/2H exchange was observed, indicating a greater solvent accessibility. The difference in Tm and TD1/2 of the protein at the abovementioned p2H's has been calculated around 20 °C. Infrared measurements have been then performed in the presence of DMPG and DOPA at p2H 4.5. DMPG showed a little destabilizing effect while DOPA exerted a great stabilizing effect, increasing the Tm of γ-conglutin at p2H 4.5 of more than 20 °C. Since γ-conglutin at p2H 4.5 is in the monomeric form, the interaction with DOPA likely promotes the oligomerization even at p2H 4.5. Interaction between DMPG or DOPA and γ-conglutin has been confirmed by turbidity experiments with DMPC:DMPG or DOPC:DOPA SUVs. Turbidity data also showed high-affinity binding of γ-conglutin to anionic SUVs made up with DOPA. The molecular features outlined in this study are relevant to address the applicative exploitation and to delineate a deeper comprehension of the natural functional role of γ-conglutin.
Interaction of γ-conglutin from Lupinus albus with model phospholipid membranes: Investigations on structure, thermal stability and oligomerization status / Scirè, Andrea; Baldassarre, Maurizio; Tanfani, Fabio; Capraro, Jessica; Duranti, Marcello; Scarafoni, Alessio. - In: BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS. - ISSN 1570-9639. - ELETTRONICO. - 1866:12(2018), pp. 1242-1248. [10.1016/j.bbapap.2018.10.005]
Interaction of γ-conglutin from Lupinus albus with model phospholipid membranes: Investigations on structure, thermal stability and oligomerization status
Scirè, Andrea
;Baldassarre, Maurizio;Tanfani, Fabio;
2018-01-01
Abstract
Interaction with model phospholipid membranes of lupin seed γ-conglutin, a glycaemia-lowering protein from Lupinus albus seeds, has been studied by means of Fourier-Transform infrared spectroscopy at p2H 7.0 and at p2H 4.5. The protein maintains the same secondary structure both at p2H 7.0 and at p2H 4.5, but at p2H 7.0 a higher 1H/2H exchange was observed, indicating a greater solvent accessibility. The difference in Tm and TD1/2 of the protein at the abovementioned p2H's has been calculated around 20 °C. Infrared measurements have been then performed in the presence of DMPG and DOPA at p2H 4.5. DMPG showed a little destabilizing effect while DOPA exerted a great stabilizing effect, increasing the Tm of γ-conglutin at p2H 4.5 of more than 20 °C. Since γ-conglutin at p2H 4.5 is in the monomeric form, the interaction with DOPA likely promotes the oligomerization even at p2H 4.5. Interaction between DMPG or DOPA and γ-conglutin has been confirmed by turbidity experiments with DMPC:DMPG or DOPC:DOPA SUVs. Turbidity data also showed high-affinity binding of γ-conglutin to anionic SUVs made up with DOPA. The molecular features outlined in this study are relevant to address the applicative exploitation and to delineate a deeper comprehension of the natural functional role of γ-conglutin.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.