INIFTA   05425
INSTITUTO DE INVESTIGACIONES FISICO-QUIMICAS TEORICAS Y APLICADAS
Unidad Ejecutora - UE
artículos
Título:
Biophysical characterisation and urea-induced unfolding of recombinant Yarrowia lipolytica sterol carrier protein-2
Autor/es:
BURGARDT, N.; FERREIRA, R.; FALOMIR-LOCKHART, L.J.; CÓRSICO, B.; CEOLÍN, M.; ERMÁCORA, M.
Revista:
BIOCHIMICA AND BIOPHYSICA ACTA
Referencias:
Año: 2009 vol. 1479 p. 1115 - 1122
ISSN:
0006-3002
Resumen:
st1:*{behavior:url(#ieooui) } <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> We report a biophysical characterisation of apo-sterol carrier protein-2 from Yarrowia lipolytica (YLSCP-2) and its urea‑induced unfolding followed by intrinsic tryptophan fluorescence, far-UV CD, ANS binding, and small angle x-ray scattering (SAXS). The unfolding is described as a three‑step process. The first steps, between 1-2 M urea, have well‑defined cooperative character and are related to the break down of most of the tertiary and secondary structure. The third step, at higher urea concentrations, is characterized by the disruption of residual interactions involving the single tryptophan. A 3D structure model for the YLSCP2 monomer was built by homology, which account for the fluorescence and CD spectroscopy data and is consistent with the binding mode observed for other SCP2. SAXS and cross-linking experiments suggest that YLSCP2 dimerise at ~70 mM concentration.