%0 Journal Article
%T Thermodynamic Stability of Psychrophilic and Mesophilic Pheromones of the Protozoan Ciliate Euplotes
%A Michael Geralt
%A Claudio Alimenti
%A Adriana Vallesi
%A Pierangelo Luporini
%A Kurt W¨ąthrich
%J Biology
%D 2013
%I MDPI AG
%R 10.3390/biology2010142
%X Three psychrophilic protein pheromones (E n-1, E n-2 and E n-6) from the polar ciliate, Euplotes nobilii, and six mesophilic pheromones (E r-1, E r-2, E r-10, E r-11, E r-22 and E r-23) from the temperate-water sister species, Euplotes raikovi, were studied in aqueous solution for their thermal unfolding and refolding based on the temperature dependence of their circular dichroism (CD) spectra. The three psychrophilic proteins showed thermal unfolding with mid points in the temperature range 55¨C70 ˇăC. In contrast, no unfolding was observed for any of the six mesophilic proteins and their regular secondary structures were maintained up to 95 ˇăC. Possible causes of these differences are discussed based on comparisons of the NMR structures of the nine proteins.
%K protein denaturation
%K protein stability
%K circular dichroism spectroscopy
%K psychrophilic proteins
%K chemical signals
%U http://www.mdpi.com/2079-7737/2/1/142