Alcohol dehydrogenase from the hyperthermophilic archaeon Pyrobaculum aerophilum: stability at high temperature.
The structural and stability properties of a novel zinc-dependent alcohol dehydrogenase from the hyperthermophilic archaeon Pyrobaculum aerophilum (PyAeADHII) were investigated by Fourier transformed infrared spectroscopy (FTIR). This enzyme is a thermostable homo-tetramer belonging to the GroES-fold motif proteins characterized by an irregular β-barrel conformation. Our results revealed a protein with a secondary structure rich in β-sheet (32% of the total secondary elements) and it showed a three-step thermal unfolding pathway. The complete enzyme denaturation was preceded by the formation of a relaxed tertiary/quaternary structure and previously by an excited native-like conformation. Two-dimensional correlation spectroscopy analysis (2D-COS) and differential scanning calorimetry (DSC) experiments supported these data and allowed us to determine the protein melting temperature at 96.9 °C as well as to suggest the sequence of the events that occurred during the protein denaturation process.
Laboratory for Molecular Sensing, IBP-CNR, Naples, Italy. a.ausili@ibp.cnr.it
Alessio
A
Ausili
Annalisa
A
Vitale
Tullio
T
Labella
Francesco
F
Rosso
Alfonso
A
Barbarisi
Juan C
JC
Gómez-Fernández
Sabato
S
D'Auria
D000426:Alcohol Dehydrogenase / Q000737:chemistry* / Q000378:metabolism*; D004795:Enzyme Stability; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D041543:Pyrobaculum / Q000201:enzymology*; D013696:Temperature
D000426:Alcohol Dehydrogenase