SAXS study of the dissassembly/unfolding of the extracellular domain of the receptor protein tyrosine phosphatase IA-2

CEOLÍN, M; RISSO, VA; ERMÁCORA, MR; PRIMO, ME; POSKUS, E; SICA, MP

Río de Janeiro, Brasil

Workshop; Workshop on Biocalorimetry and Biological Thermodynamics; 2006

The receptor protein tyrosine phosphatase superfamily (RPTP) includes proteins with a single transmembrane, one or more intracellular phosphatase, and a variety of extracellular domains (IA2-ec among others). We decided to study IA-2ec because this fragment comprises the extracellular domain of mature IA-2 and therefore must be considered in the first place in a search for an independently folding subunit. For this study, IA-2ec was expressed in E. coli as a histidine-tagged protein. The product was soluble and well folded. Herein, we report a preliminary conformational characterization of IA-2ec Small Angle X-ray Scattering (SAXS), Dynamic Light Scattering (DLS) and Circular Dichroism Spectroscopy (CD)