Author(s): Laura Riccardi1, Papaleo Elena2 *
Journal: The IIOAB Journal
ISSN 0976-3104
Volume: 1;
Issue: 4;
Start page: 11;
Date: 2010;
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Keywords: cold-adapted enzymes | unfolding | molecular dynamics simulations | psychrophilic enzymes | elastase | serine-protease
ABSTRACT
The earth surface is dominated by low temperature environments, which have been successfully colonized by several extremophilic organisms. Enzymes isolated from psychrophilic organisms are able to catalyze reactions at low temperatures at which enzymes from mesophiles or thermophiles are fully compromised. The current scenario on enzyme cold-adaptation suggest that these enzymes are characterized by higher catalytic efficiently at low temperatures, enhanced structural flexibility and lower thermostability. In the present contribution, molecular dynamics simulations in explicit solvent have been carried out at different high temperatures in order to investigate the unfolding process of cold- and warm-adapted homologous enzymes. In particular, we focused our attention on cold-adapted elastases for which it was previously demonstrated that the psychrophilic enzyme presents higher localized flexibility in loops surrounding the catalytic site and the specificity pocket. The unfolding simulations show a slower unfolding process for the cold-adapted enzyme, but characterized by a greater loss of intramolecular interactions and α-helices than the mesophilic counterparts.
Journal: The IIOAB Journal
ISSN 0976-3104
Volume: 1;
Issue: 4;
Start page: 11;
Date: 2010;
VIEW PDF
DOWNLOAD PDF Original pageKeywords: cold-adapted enzymes | unfolding | molecular dynamics simulations | psychrophilic enzymes | elastase | serine-protease
ABSTRACT
The earth surface is dominated by low temperature environments, which have been successfully colonized by several extremophilic organisms. Enzymes isolated from psychrophilic organisms are able to catalyze reactions at low temperatures at which enzymes from mesophiles or thermophiles are fully compromised. The current scenario on enzyme cold-adaptation suggest that these enzymes are characterized by higher catalytic efficiently at low temperatures, enhanced structural flexibility and lower thermostability. In the present contribution, molecular dynamics simulations in explicit solvent have been carried out at different high temperatures in order to investigate the unfolding process of cold- and warm-adapted homologous enzymes. In particular, we focused our attention on cold-adapted elastases for which it was previously demonstrated that the psychrophilic enzyme presents higher localized flexibility in loops surrounding the catalytic site and the specificity pocket. The unfolding simulations show a slower unfolding process for the cold-adapted enzyme, but characterized by a greater loss of intramolecular interactions and α-helices than the mesophilic counterparts.
