title: Protein thermal stability: the role of protein structure and aqueous environment.
abstract: A comprehensive bioinformatic analysis was performed on all protein homologous pairs from mesophilic and thermophilic microorganisms present in the RCSB Protein Data Bank in order to yield a clue on the role of protein structure and aqueous environment. Subsequently self-assembly and LB studies were carried out at increasing temperature by nanogravimetry with thermostable thioredoxin (Trx) from Alicyclobacillus acidocaldarius (BacTrx) versus the mesophilic Escherichia coli counterpart (EcTrx). The comparison with earlier 3D atomic structure determined on the same proteins by X-ray crystallographic diffraction and nuclear magnetic resonance confirm the role inner bound water in determining protein thermostability, as suggested by the bioinformatic and nanogravimetric analysis. The above comparative characterizations in protein solution, thin film and crystal allow to draw a possible coherent explanation for the origin and the molecular mechanisms of both heat stability and radiation resistance in proteins.
authors.affiliation: Nanoworld Institute, University of Genova, Corso Europa 30, 16132 Genova, Italy.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Pechkova
authors.forename: Victor
authors.initials: V
authors.lastname: Sivozhelezov
authors.forename: Claudio
authors.initials: C
authors.lastname: Nicolini
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D003198:Computer Simulation; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D020539:Sequence Analysis, Protein / Q000379:methods*; D012997:Solvents / Q000737:chemistry; D013329:Structure-Activity Relationship; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D012997:Solvents; D014867:Water