tailieunhanh - Báo cáo khoa học: Structural study of the catalytic domain of PKCf using infrared spectroscopy and two-dimensional infrared correlation spectroscopy

The secondary structure of the catalytic domain from protein kinase Cf was studied using IR spectroscopy. In the presence of the substrate MgATP, there was a significant change in the secondary structure. After heating to 80 C, a 14% decrease in thea-helix component was observed, accompanied by a 6% decrease in the b-pleated sheet; no change was observed in the large loops or in 310 -helix plus associated loops. | ềFEBS Journal Structural study of the catalytic domain of PKCf using infrared spectroscopy and two-dimensional infrared correlation spectroscopy Sonia Sanchez-Bautista Andris Kazaks Melanie Beaulande Alejandro Torrecillas Senena Corbalán-García and Juan C. Gomez-Fernandez Departamento de Bioquimica y Biologia Molecular Universidad de Murcia Spain Keywords 2D-correlation catalytic domain FTIR protein kinase C protein structure Correspondence J. C. Gomez-Fernandez Departamento de Bioquimica y Biologia Molecular A Facultad de Veterinaria Universidad de Murcia Apartado de Correos 4021 E-30080 Murcia Spain Fax 34 968 36 4766 Tel 34 968 36 4766 E-mail jcgomez@ Present address BiomedicalResearch and Study Centre University of Latvia Riga Latvia Received 27 January 2006 revised 22 May 2006 accepted 23 May 2006 doi The secondary structure of the catalytic domain from protein kinase C f was studied using IR spectroscopy. In the presence of the substrate MgATP there was a significant change in the secondary structure. After heating to 80 C a 14 decrease in the a-helix component was observed accompanied by a 6 decrease in the b-pleated sheet no change was observed in the large loops or in 310-helix plus associated loops. The maximum increase with heating was observed in the aggregated b-sheet component with an increase of 14 . In the presence of MgATP and compared with the sample heated in its absence there was a substantial decrease in the 310-helix plus associated loops and an increase in a-helix. Synchronous 2D-IR correlation showed that the main changes occurred at 1617 cm-1 which was assigned to changes in the intermolecular aggregated b-sheet of the denaturated protein. This increase was mainly correlated with the change in a-helix. In the presence of MgATP the main correlation was between aggregated b-sheet and the large loops component. The asynchronous 2D-correlation spectrum indicated that a number of components are transformed .