Autor(es)

Chagas, Rafael S. ; Marana, Sandro R.

• Tipo de documento: Artigo Científico
• Fonte: ACS OMEGA; v. 10, n. 32, p. 10-pg., 2025-08-07.

Resumo

Oligomerization is a key feature of protein function, with approximately 30% of proteins exhibiting this trait. The homodimeric form of proteins, such as the GH1 beta-glucosidase from Spodoptera frugiperda (Sf beta gly), plays a significant role in enzyme activity. In this study, we investigate the homodimerization of Sf beta gly, which forms a cyclic C2 dimer with a well-defined interface. Using size exclusion chromatography and SEC-MALS, we characterized the homodimerization behavior of Sf beta gly at equilibrium conditions in different ionic concentrations of phosphate buffer. The dissociation constants (K D) increase with decreasing ionic concentration, suggesting that the hydrophobic effect is central to homodimer formation. Site-directed mutagenesis of key residues at the dimer interface further elucidated the contributions of specific amino acid residues to dimer stability. Mutations affecting both, apolar and hydrogen bond-forming residues, significantly increased the K D. However, mutations of hydrogen bond-forming residues caused a smaller K D change than apolar residue mutations, suggesting that while the latter is the driving factor in the dimerization, the former could play a role in guiding the monomers relative orientation. These findings enhance our understanding of protein oligomerization in GH1 beta-glucosidases and its implications for protein design and function. (AU)

• Processo FAPESP: 21/03967-6 - Caracterização da interface dimérica de uma beta-glicosidase
• Beneficiário: Sandro Roberto Marana
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 21/10577-0 - Centro de Pesquisa em Biologia de Bactérias e Bacteriófagos (CEPID B3)
• Beneficiário: Shaker Chuck Farah
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs