Environmental ConditionsModulate the Switch amongDifferent States of the Hydrophobin Vmh2 from Pleurotusostreatus.

Fungal hydrophobins are amphipathic, highly surface-active,andself-assembling proteins. The class I hydrophobin Vmh2 from the basidiomycetefungus Pleurotus ostreatusseems tobe the most hydrophobic hydrophobin characterized so far. Structuraland functional properties of the protein as a function of the environmentalconditions have been determined. At least three distinct phenomenacan occur, being modulated by the environmental conditions: (1) whenthe pH increases or in the presence of Ca2誉, an assembledstate, β-sheet rich, is formed; (2) when the solvent polarityincreases, the protein shows an increased tendency to reach hydrophobic/hydrophilicinterfaces, with no detectable conformational change; and (3) whena reversible conformational change and reversible aggregation occurat high temperature. Modulation of the Vmh2 conformational/aggregationfeatures by changing the environmental conditions can be very usefulin view of the potential protein applications. [ABSTRACT FROM AUTHOR]