Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
CONFORMATIONS OF SYNTHETIC BETA-PEPTIDES IN SOLID-STATE AND IN AQUEOUS-SOLUTION - RELATION TO TOXICITY IN PC12 CELLS
Autore:
BUCHET R; TAVITIAN E; RISTIG D; SWOBODA R; STAUSS U; GREMLICH HU; DELAFOURNIERE L; STAUFENBIEL M; FREY P; LOWE DA;
Indirizzi:
UNIV LYON 1,CNRS URA 1535,LAB PHYS CHIM BIOL,BAT 303,43 BD 11 NOVEMBRE F-69622 VILLEURBANNE FRANCE SANDOZ RES INST BERNE LTD CH-3001 BERN SWITZERLAND SANDOZ PHARMA LTD CH-4002 BASEL SWITZERLAND
Titolo Testata:
Biochimica et biophysica acta. Molecular basis of disease
fascicolo: 1, volume: 1315, anno: 1996,
pagine: 40 - 46
SICI:
0925-4439(1996)1315:1<40:COSBIS>2.0.ZU;2-Y
Fonte:
ISI
Lingua:
ENG
Soggetto:
ALZHEIMERS-DISEASE; AMYLOID PROTEIN; CIRCULAR-DICHROISM; NEUROTOXICITY; DEPOSITION; FRAGMENTS; REVERSAL; NEURONS; INVITRO; DAMAGE;
Keywords:
BETA PEPTIDE; CIRCULAR DICHROISM; FOURIER-TRANSFORM INFRARED SPECTROSCOPY; TOXICITY; PC 12 CELL; SECONDARY STRUCTURE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
35
Recensione:
Indirizzi per estratti:
Citazione:
R. Buchet et al., "CONFORMATIONS OF SYNTHETIC BETA-PEPTIDES IN SOLID-STATE AND IN AQUEOUS-SOLUTION - RELATION TO TOXICITY IN PC12 CELLS", Biochimica et biophysica acta. Molecular basis of disease, 1315(1), 1996, pp. 40-46

Abstract

The secondary structures of peptides beta 25-35 (the active toxic fragment) and beta 35-25 (reverse sequence and non-toxic fragment), as well as of the amidated beta(25-35)-NH2 peptide were investigated in aqueous solution and in the solid state by moans of Fourier-transformed infrared spectroscopy and circular dichroism spectroscopy, The conformations of the beta 25-35 and beta 35-25 in solid state were identical and contained mostly beta-sheet structures, In the solid state the amidated beta(25-35)-NH2 peptide also contained mostly beta-sheet structures. Freshly prepared aqueous solutions of the beta 25-35 (0.5-3.8 mM) contained a mixture of beta-sheet and random coil structures, Within 30-60 min incubation at 37 degrees C in water or in phosphate-buffered saline solution (PBS). beta 25-35 was almost fully converted to a beta-sheet structure. Decreasing the temperature from 37 degrees C to 20 degrees C decreased the rate of conversion from random coil to beta-sheet structures, 1-2 h being required for complete conversion. In contrast beta 35-25 in water or in PBS buffer had mostly a random coil structure and remained so for 6 days. The amidated beta(25-35)-NH2 peptide in water (2.7 mM) was also mostly random coil. However, when this peptide (2-2.7 mM) was dissolved in PBS (pH 7.4) or in 140 mM NaCl, a gel was formed and its conformation was mostly beta-sheet. Decreasing the concentration of beta(25-35)-NH2 peptide in 140 mM NaCl aqueous solution from 2 mM to 1 mM or below favored the conversion from beta-sheet structures to random coil structures. The beta 25-35 was toxic to PC12.cells while beta 35-25 was not, The amidated peptide beta(25-35)-NH2 was at least 500-fold less toxic than beta 25-35, Structural differences between these beta peptides in aqueous solutions may explain the difference in their respective toxicities.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 21/09/20 alle ore 19:16:26