Sebastian T. Mergelsberg , Hoshin Kim , Garry W. Buchko , Bojana Ginovska
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引用次数: 0
Abstract
Amelogenin is an intrinsically disordered protein essential to tooth enamel formation in mammals. Using advanced small angle X-ray scattering (SAXS) capabilities at synchrotrons and computational models, we revisited measuring the quaternary structure of murine amelogenin as a function of pH and phosphorylation at serine-16. The SAXS data shows that at the pH extremes, amelogenin exists as an extended monomer at pH 3.0 (Rg = 38.4 Å) and nanospheres at pH 8.0 (Rg = 84.0 Å), consistent with multiple previous observations. At pH 5.0 and above there was no evidence for a significant population of monomeric species. Instead, at pH 5.0, ∼80 % of the population is a heterogenous dimeric species that increases to ∼100 % at pH 5.5. The dimer population was observed at all pH > 5 conditions in dynamic equilibrium with a species in the pentamer range at pH < 6.5 and nanospheres at pH 8.0. At pH 8.0, ∼40 % of the amelogenin remained in the dimeric state. In general, serine-16 phosphorylation of amelogenin appears to modestly stabilize the population of the dimeric species.
期刊介绍:
Journal of Structural Biology (JSB) has an open access mirror journal, the Journal of Structural Biology: X (JSBX), sharing the same aims and scope, editorial team, submission system and rigorous peer review. Since both journals share the same editorial system, you may submit your manuscript via either journal homepage. You will be prompted during submission (and revision) to choose in which to publish your article. The editors and reviewers are not aware of the choice you made until the article has been published online. JSB and JSBX publish papers dealing with the structural analysis of living material at every level of organization by all methods that lead to an understanding of biological function in terms of molecular and supermolecular structure.
Techniques covered include:
• Light microscopy including confocal microscopy
• All types of electron microscopy
• X-ray diffraction
• Nuclear magnetic resonance
• Scanning force microscopy, scanning probe microscopy, and tunneling microscopy
• Digital image processing
• Computational insights into structure