SDS-resistant Active and Thermostable Dimers Are Obtained from the Dissociation of Homotetrameric b-glycosidase From Hyperthermophilic Sulfolobus Solfataricus in SDS. Stabilizing Role of the A-C Intermonomeric Interface

Autor: Gentile F., Amodeo P., Febbraio F., Picaro F., Motta A. Formisano S., Nucci R.
Jazyk: angličtina
Rok vydání: 2002
Předmět:
Zdroj: The Journal of biological chemistry
277 (2002): 44050–44060. doi:10.1074/jbc.M206761200
info:cnr-pdr/source/autori:Gentile F., Amodeo P., Febbraio F., Picaro F., Motta A. Formisano S., Nucci R./titolo:SDS-resistant Active and Thermostable Dimers Are Obtained from the Dissociation of Homotetrameric b-glycosidase From Hyperthermophilic Sulfolobus Solfataricus in SDS. Stabilizing Role of the A-C Intermonomeric Interface/doi:10.1074%2Fjbc.M206761200/rivista:The Journal of biological chemistry (Print)/anno:2002/pagina_da:44050/pagina_a:44060/intervallo_pagine:44050–44060/volume:277
Popis: beta-Glycosidases are fundamental, widely conserved enzymes. Those from hyperthermophiles exhibit unusual stabilities toward various perturbants. Previous work with homotetrameric beta-glycosidase from hyperthermophilic Sulfolobus solfataricus (M(r) 226,760) has shown that addition of 0.05- 0.1% SDS was associated with minimal secondary structure perturbations and increased activity. This work addresses the effects of SDS on beta-glycosidase quaternary structure. In 0.1-1% SDS, the enzyme was dimeric, as determined by Ferguson analysis of transverse-gradient polyacrylamide gels. The catalytic activity of the beta-glycosidase dimer in SDS was determined by in-gel assay. A minor decrease of thermal stability in SDS was observed after exposure to temperatures up to 80 degrees C for 1 h. An analysis of beta-glycosidase crystal structure showed different changes in solvent-accessible surface area on going from the tetramer to the two possible dimers (A-C and A-D). Energy minimization and molecular dynamics calculations showed that the A-C dimer, exhibiting the lowest exposed surface area, was more stabilized by a network of polar interactions. The charge distribution around the A-C interface was characterized by a local short range anisotropy, resulting in an unfavorable interaction with SDS. This paper provides a detailed description of an SDS-resistant inter-monomeric interface, which may help understand similar interfaces involved in important biological processes.
Databáze: OpenAIRE