The synthetic peptide Vitr-p-13 (YPIVGQELLGAIK-NH2), derived from the bacterial dimeric Vitreoscilla haemoglobin (VHb) in the position 95–107, is characterized by a preeminent ‘‘statistical coil’’ conformation in water as demonstrated by CD experiments and long time-scaleMD simulations. In particular, Vitr-p-13 does not spontaneously adopt an alpha-helix folding in water, but it is rather preferentially found in beta-hairpin-like conformations. Long time-scale MD simulations have also shown that Vitrp- 13 displays a ‘‘topological-trigger’’ which initiates alphahelix folding within residues 7–10, exactly like seen in the temporins, a group of linear, membrane-active antimicrobial peptides of similar length. At variance with temporins, in Vitr-p-13 such a process is energetically very demanding (110 kJ/mol) in water at 300 K, and the peptide was found to be unable to bind model membranes in vitro and was devoid of antimicrobial activity. The present results, compared with previous studies on similar systems, strengthen the hypothesis of the requirement of a partial folding when still in aqueous environment to allow a peptide to interact with cell-membranes and eventually exert membrane perturbation-related antibiotic effects on target microbial cells.

Folding propensity and biological activity of peptides: New insights from conformational properties of a novel peptide derived from Vitreoscilla haemoglobin / Bozzi, A; Coccia, C; DI GIULIO, A; RINALDI A., C; Amadei, A; Mignogna, Giuseppina; Bonamore, Alessandra; Feis, A; Aschi, M.. - In: BIOPOLYMERS. - ISSN 0006-3525. - 87:(2007), pp. 85-92. [10.1002/bip.20792]

Folding propensity and biological activity of peptides: New insights from conformational properties of a novel peptide derived from Vitreoscilla haemoglobin.

MIGNOGNA, Giuseppina;BONAMORE, ALESSANDRA;
2007

Abstract

The synthetic peptide Vitr-p-13 (YPIVGQELLGAIK-NH2), derived from the bacterial dimeric Vitreoscilla haemoglobin (VHb) in the position 95–107, is characterized by a preeminent ‘‘statistical coil’’ conformation in water as demonstrated by CD experiments and long time-scaleMD simulations. In particular, Vitr-p-13 does not spontaneously adopt an alpha-helix folding in water, but it is rather preferentially found in beta-hairpin-like conformations. Long time-scale MD simulations have also shown that Vitrp- 13 displays a ‘‘topological-trigger’’ which initiates alphahelix folding within residues 7–10, exactly like seen in the temporins, a group of linear, membrane-active antimicrobial peptides of similar length. At variance with temporins, in Vitr-p-13 such a process is energetically very demanding (110 kJ/mol) in water at 300 K, and the peptide was found to be unable to bind model membranes in vitro and was devoid of antimicrobial activity. The present results, compared with previous studies on similar systems, strengthen the hypothesis of the requirement of a partial folding when still in aqueous environment to allow a peptide to interact with cell-membranes and eventually exert membrane perturbation-related antibiotic effects on target microbial cells.
2007
MOLECULAR DYNAMICS; free energy; circular dichroism; Vitreoscilla Hb
01 Pubblicazione su rivista::01a Articolo in rivista
Folding propensity and biological activity of peptides: New insights from conformational properties of a novel peptide derived from Vitreoscilla haemoglobin / Bozzi, A; Coccia, C; DI GIULIO, A; RINALDI A., C; Amadei, A; Mignogna, Giuseppina; Bonamore, Alessandra; Feis, A; Aschi, M.. - In: BIOPOLYMERS. - ISSN 0006-3525. - 87:(2007), pp. 85-92. [10.1002/bip.20792]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/239779
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