β-glycosidase from the hyperthermophilic archaeon Sulfolobus solfataricus: Structure and activity in the presence of alcohols

Sabato D'Auria, Roberto Nucci, Mose' Rossi, Enrico Bertoli, Fabio Tanfani, Ignacy Gryczynski, Henry Malak, Joseph R. Lakowicz

Research output: Contribution to journalArticlepeer-review

32 Scopus citations

Abstract

β-Glycosidase from the extreme thermophilic archaeon Sulfolobus solfataricus is a tetrameric protein with a molecular mass of 240 kDa, stable in the presence of detergents, and with a maximal activity at temperatures above 95°C. Understanding the structure-activity relationships of the enzyme under different conditions is of fundamental importance for both theoretical and applicative purposes. In this paper we report the effect of methanol, ethanol, 1-propanol, and 1-butanol on the activity of S. solfataricus β-glycosidase expressed in Escherichia coli. The alcohols stimulated the enzyme activity, with 1-butanol producing its maximum effect at a lower concentration than the other alcohols. The structure of the enzyme was studied in the presence of 1-butanol by circular dichroism and Fourier-transform infrared and fluorescence spectroscopies. Circular dichroism and steady-state fluorescence measurements revealed that at low temperatures the presence of the alcohol produced no significant changes in the tertiary structure of the enzyme. However, time-resolved fluorescence data showed that the alcohol modifies the protein microenvironment, leading to a more flexible enzyme structure, which is probably responsible for the enhanced enzymatic activity.

Original languageEnglish
Pages (from-to)545-552
Number of pages8
JournalJournal of Biochemistry
Volume126
Issue number3
DOIs
StatePublished - 1999

Keywords

  • Archaeon
  • Circular dichroism
  • Frequency domain fluorometry
  • Infrared spectroscopy
  • Organic solvent
  • β-glycosidase

Fingerprint

Dive into the research topics of 'β-glycosidase from the hyperthermophilic archaeon Sulfolobus solfataricus: Structure and activity in the presence of alcohols'. Together they form a unique fingerprint.

Cite this