Descrizione: Common proteins and enzymes are generally functional under mild conditions of pH, temperature and pressure. On the other hand, enzymes and proteins isolated from organisms living in ecosystems with extreme conditions in terms of temperature, pH, and pressure, are capable of functioning efficiently in extreme environments. The characterization of these enzymes/proteins may provide information to improve stability, activity and specificity of many enzymes used as industrial biocatalysts/biosensors. In this framework, intense research activities are carried out at the IBB to unveil structure-function relationships in proteins isolated from organisms living in unusual conditions. Most of the efforts are devoted to proteins of organisms living in extreme temperature conditions. Indeed, current studies are carried out on several classes of proteins isolated from termophilic (thioredoxins, thioredoxin reductases, elongation/exchange factors, dehydrogenases, transport proteins, esterases, DNA binding proteins and Protein disulfide oxidoreductases, Peroxiredoxins) and psychrophilic (esterases/lipases) bacteria. In parallel, hemoproteins isolated from fishes living at very low temperature in the Arctic or Antarctic Oceans are also under investigation
Figure 1. The crystal structure of the Sulfolobus solfataricus Thioredoxin reductase B3
Figure 2. The crystal structure of the transcription factor BldR from Sulfolobus solfataricus
Contursi P, D'Ambrosio K, Pirone L, Pedone E, Aucelli T, She Q, De Simone G, Bartolucci S. Biochem J. 2011; 435: 157-66Vergara A, Vitagliano L, Merlino A, Sica F, Marino K, Verde C, di Prisco G, Mazzarella L. An order-disorder transition plays a role in switching off the root effect in fish hemoglobins. J Biol Chem. 2010, 285: 32568-75. Pedone E, Limauro D, D'Ambrosio K, De Simone G, Bartolucci S. Multiple catalytically active thioredoxin folds: a winning strategy for many functions. Cell Mol Life Sci. 2010 Nov; 67 (22): 3797-814. Limauro D, D'Ambrosio K, Langella E, De Simone G, Galdi I, Pedone C, Pedone E, Bartolucci S. Exploring the catalytic mechanism of the first dimeric Bcp: Functional, structural and docking analyses of Bcp4 from Sulfolobus solfataricus. Biochimie. 2010 Oct; 92 (10): 1435-44. Ruggiero A, Masullo M, Marasco D, Ruocco MR, Grimaldi P, Arcari P, Zagari A, Vitagliano L. The dimeric structure of Sulfolobus solfataricus thioredoxin A2 and the basis of its thermostability. Proteins. 2009. 77: 1004-8. Merlino A, Vitagliano L, Howes BD, Verde C, di Prisco G, Smulevich G, Sica F, Vergara A. Combined crystallographic and spectroscopic analysis of Trematomus bernacchii hemoglobin highlights analogies and differences in the peculiar oxidation pathway of Antarctic fish hemoglobins. Biopolymers. 2009 91: 1117-1125. Ruggiero A, Masullo M, Ruocco MR, Grimaldi P, Lanzotti MA, Arcari P, Zagari A, Vitagliano L. Structure and stability of a thioredoxin reductase from Sulfolobus solfataricus: A thermostable protein with two functions. Biochim Biophys Acta. 2009 1794: 554-62. Di Fiore A, Fiorentino G, Vitale RM, Ronca R, Amodeo P, Pedone C, Bartolucci S, De Simone G. J Mol Biol. 2009; 388: 559-69. Pennacchio A, Esposito L, Zagari A, Rossi M, Raia CA. Role of tryptophan 95 in substrate specificity and structural stability of Sulfolobus solfataricus alcohol dehydrogenase. Extremophiles. 2009 13: 751-61. Vitagliano L, Vergara A, Bonomi G, Merlino A, Verde C, di Prisco G, Howes BD, Smulevich G, Mazzarella L. Spectroscopic and crystallographic characterizationof a tetrameric hemoglobin oxidation pathway reveals structural features of a functional intermediate R/T state. J Am Chem Soc. 2008 130: 10527-35. Pedone E, D'Ambrosio K, De Simone G, Rossi M, Pedone C, Bartolucci S. Insights on a New PDI-like Family: Structural and Functional Analysis of a Protein Disulfide Oxidoreductase from the Bacterium Aquifex aeolicus. J Mol Biol. 356 (1): 155-64, 2006. De Simone G, Mandrich L, Menchise V, Giordano V, Febbraio F, Rossi M, Pedone C, Manco G. J Biol Chem. 2004; 279: 6815-23. Esposito L, Bruno I, Sica F, Raia CA, Giordano A, Rossi M, Mazzarella L, Zagari A. Crystal structure of a ternary complex of the alcohol dehydrogenase from Sulfolobus solfataricus. Biochemistry. 2003 42: 14397-407.