2yxf
From Proteopedia
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The high resolution crystal structure of beta2-microglobulin under physiological conditions
Overview
beta(2)-Microglobulin (beta2-m), a light chain of the major, histocompatibility complex class I, forms amyloid fibrils in patients, undergoing long-term haemodialysis, causing dialysis-related amyloidosis., Based on a comparison of the X-ray structure obtained at pH 5.7 and that, of beta2-m in the histocompatibility complex, it has been proposed that, the continuous D-strand observed in the crystal structure at pH 5.7, increases the propensity of beta2-m to self-associate via edge-to-edge, interactions, thus initiating the formation of fibrils. To obtain further, insight into the mechanism by which amyloid fibrils form, we determined, the crystal structure of beta2-m at pH 7.0 at a resolution of up to 1.13, A. The crystal structure at pH 7.0 was basically the same as that at pH, 5.6, suggesting that the conversion of the beta-bulge in strand D into a, contiguous beta-strand is not unique to the crystals formed under slightly, acidic conditions. In other words, although the formation of beta2-m, fibrils was enhanced under acidic conditions, it remains unknown if it is, related to the increased propensity for the disappearance of the, beta-bulge in strand D. We consider that the enhanced fibrillation is more, directly coupled with the decreased stability leading to the increased, propensity of exposing amyloidogenic regions.
About this Structure
2YXF is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
High-resolution Crystal Structure of {beta}2-Microglobulin Formed at pH 7.0., Iwata K, Matsuura T, Sakurai K, Nakagawa A, Goto Y, J Biochem (Tokyo). 2007 Sep;142(3):413-9. Epub 2007 Jul 23. PMID:17646174
Page seeded by OCA on Wed Jan 23 12:39:22 2008
