Conformation of the N-Terminal Fragment of Human Salivary Statherin

doi:10.11938/cjmr20150211

Abstract

Abstract:

Human salivary statherin is a 43-residue acidic phosphoprotein present in human saliva, possessing a high affinity for calcium phosphate minerals such as hydroxyapatite. The N-terminal 15-residue fragment of statherin (SN-15) is known to bind strongly to the crystallites of hydroxyapatite. In this work, we investigate the conformation of SN-15 in aqueous solution by NMR. Analysis of the CD spectra shows that SN-15 adopts an α-helical structure in phosphate buffer. High-resolution proton NMR spectra (COSY, TOCSY, and NOESY) have been acquired, from which the NOE patterns and J-couplings of amide hydrogens have been obtained. Together with the constraints obtained from amide-hydrogen exchange experiments, the molecular structure of SN-15 has shown to be a continuous α-helical structure.

Key words: biomineralization, HAp, SN-15

CLC Number:

O482.53

GUO Syuan-ming, CHANG Chi-fon, CHAN Jerry C C. Conformation of the N-Terminal Fragment of Human Salivary Statherin[J]. Chinese Journal of Magnetic Resonance, 2015, 32(2): 283-290.

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