دورية أكاديمية

Thermal Stability and Aggregation of Sulfolobus solfataricus β-Glycosidase Are Dependent upon the N-ε-Methylation of Specific Lysyl Residues.

التفاصيل البيبلوغرافية
العنوان: Thermal Stability and Aggregation of Sulfolobus solfataricus β-Glycosidase Are Dependent upon the N-ε-Methylation of Specific Lysyl Residues.
المؤلفون: Febbraio, Ferdinando1 f.febbraio@ibp.cnr.it, Andolfo, Annapaola2, Tanfani, Fabio3,4, Briante, Raffaella1, Gentile, Fabrizio5, Formisano, Silvestro6, Vaccaro, Carlo1, Scirè, Andrea3,7, Bertoli, Enrico3,7, Pucci, Piero2,8, Nucci, Roberto1
المصدر: Journal of Biological Chemistry. 3/12/2004, Vol. 279 Issue 11, p10185-10194. 10p. 2 Black and White Photographs, 2 Diagrams, 2 Charts, 11 Graphs.
مصطلحات موضوعية: *METHYLATION, *BACTERIA, *ARCHAEBACTERIA, *BIOCHEMISTRY, *BIOLOGY, *CHEMISTRY
مستخلص: Methylation in vivo is a post-translational modification observed in several organisms belonging to eucarya, bacteria, and archaea. Although important implications of this modification have been demonstrated in several eucaryotes, its biological role in hyperthermophillc archaea is far from being understood. The aim of this work is to clarify some effects of methylation on the properties of β-glycosidase from Sulfolobus solfataricus, by a structural comparison between the native, methylated protein and its unmethylated counterpart, recombinantly expressed in Escherichia coli. Analysis by Fourier transform infrared spectroscopy indicated similar secondary structure contents for the two forms of the protein. However, the study of temperature perturbation by Fourier transform infrared spectroscopy and turbidimetry evidenced denaturation and aggregation events moro pronounced in recombinant than in native β-glycosidase. Red Nile fluorescence analysis revealed significant differences of surface hydrophobicity between the two forms of the protein. Unlike the native enzyme, which dissociated into SDS-rosistant dimers upon exposure to the detergent, the recombinant enzyme partially dissociated into monomers. By electrospray mapping, the methylation sites of the native protein were identified. A computational analysis of β-glycosidase three-dimensional structuro and comparisons with other proteins from S. solfataricus revealed analogies in the localization of methylation sites in terms of secondary structural elements and overall topology. These observations suggest a role for the methylation of lysyl residues, located in selected domains, in the thermal stabilization of β-giycosidase from S. solfataricus. [ABSTRACT FROM AUTHOR]
قاعدة البيانات: Academic Search Index
الوصف
تدمد:00219258
DOI:10.1074/jbc.M308520200