caa a22 4500 397556969 CHVBK 20180308164805.0 cr unu---uuuuu 161202e199608 xx s 000 0 eng 10.1093/oxfordjournals.jbchem.a021412 doi (NATIONALLICENCE)oxford-10.1093/oxfordjournals.jbchem.a021412 Temperature-Induced Denaturation of β-Glycosidase from the Archaeon Sulfolobus solfataricus [Elektronische Daten] [Sabato D'Auria, Mosè Rossi, Guido Barone, Francesca Catanzano, Pompea Del Vecchio, Giuseppe Graziano, Roberto Nucci] The β-glycosidase isolated from the extreme thermophilic archaeon Sulfolobus solfataricus, grown at 87°C, is a tetrameric protein with a molecular mass of 240 kDa. This enzyme is barely active at 30°C and has optimal activity, over 95°C, at pH 6.5. Its thermal stability was investigated at pH 10.1 and 10.6 by means of functional studies, circular dichroism and differential scanning calorimetry. There was no evidence of thermal activation of the enzyme and the temperature-induced denaturation was irreversible and not well represented by the two-state transition model. A more complex process occurred, involving the dissociation and unfolding of subunits, and subsequent nonspecific association and/or aggregation. Denaturation temperature was around 85°C, depending on protein concentration. The denaturation enthalpy change was between 7,500 and 9,800 kJ-mol−1, depending on the pH. The collapse of the native structure around 85°C was confirmed by circular dichroism measurements and time-dependent activity studies. Finally, preliminary investigations were performed on the recombinant enzyme expressed in Escherichia coli. © 1996 BY THE JOURNAL OF BIOCHEMISTRY Regular Papers nationallicence β-glycosidase nationallicence Sulfolobus solfataricus nationallicence thermophilic enzyme nationallicence protein denaturation nationallicence scanning calorimetry nationallicence D'Auria Sabato Institute of Protein Biochemistry and Enzymology, National Research Council Via Marconi 10-80125 Naples, Italy aut Rossi Mosè Institute of Protein Biochemistry and Enzymology, National Research Council Via Marconi 10-80125 Naples, Italy aut Barone Guido Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut Catanzano Francesca Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut Vecchio Pompea Del Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut Graziano Giuseppe Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut Nucci Roberto Institute of Protein Biochemistry and Enzymology, National Research Council Via Marconi 10-80125 Naples, Italy aut The Journal of Biochemistry Oxford University Press 120/2(1996-08), 292-300 0021-924X 120:2<292 1996 120 jbchem https://doi.org/10.1093/oxfordjournals.jbchem.a021412 text/html Onlinezugriff via DOI 1 other jats NATIONALLICENCE 856 40 https://doi.org/10.1093/oxfordjournals.jbchem.a021412 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- D'Auria Sabato Institute of Protein Biochemistry and Enzymology, National Research Council Via Marconi 10-80125 Naples, Italy aut NATIONALLICENCE 700 1- Rossi Mosè Institute of Protein Biochemistry and Enzymology, National Research Council Via Marconi 10-80125 Naples, Italy aut NATIONALLICENCE 700 1- Barone Guido Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut NATIONALLICENCE 700 1- Catanzano Francesca Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut NATIONALLICENCE 700 1- Vecchio Pompea Del Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut NATIONALLICENCE 700 1- Graziano Giuseppe Department of Chemistry, University of Naples "Federico II” Via Mezzocannone 4-80134 Naples, Italy aut NATIONALLICENCE 700 1- Nucci Roberto Institute of Protein Biochemistry and Enzymology, National Research Council Via Marconi 10-80125 Naples, Italy aut NATIONALLICENCE 773 0- The Journal of Biochemistry Oxford University Press 120/2(1996-08), 292-300 0021-924X 120:2<292 1996 120 jbchem Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford