Adsorption of a statherin peptide fragment on the surface of nanocrystallites of hydroxyapatite.
Statherin is an active inhibitor of calcium phosphate precipitation in the oral cavity. For many studies of the interaction between statherin and hydroxyapatite (HAp), the samples are prepared by a direct mixing of statherin or its fragment with well-crystalline HAp crystals. In this work, the HAp sample is precipitated in the presence of peptide fragment derived from the N-terminal 15 amino acids of statherin (SN-15). The in situ prepared HAp crystallites are nanosized, leading to a significant increase of the peptide amount adsorbed on the HAp surface. The enhancement in NMR sensitivity allows, for the first time, the measurement of a two-dimensional 13C-13C correlation spectrum for a 13C uniformly labeled peptide sample adsorbed on mineral surface. The measurement time is about 18.5 h at a field strength of 7.05 T. Preliminary results suggest that there may exist two different mechanisms for the interaction between SN-15 and HAp. In addition to the one which will cause a conformational change near the N-terminal, SN-15 may also be absorbed on the HAp surface by simple electrostatic interaction, without any significant conformational changes of the peptides.
Chen
Peng-Huan
PH
Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei 106, Taiwan.
Tseng
Yao-Hung
YH
Mou
Yun
Y
Tsai
Yi-Ling
YL
Guo
Syuan-Ming
SM
Huang
Shing-Jong
SJ
Yu
Steve S-F
SS
Chan
Jerry C C
JC
D000327:Adsorption; D002247:Carbon Isotopes; D003460:Crystallization; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D049329:Nanostructures / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry*; D012015:Reference Standards; D012471:Salivary Proteins and Peptides / Q000737:chemistry*; D055672:Static Electricity; D013499:Surface Properties
D002247:Carbon Isotopes; D010446:Peptide Fragments; C018149:STATH protein, human; D012471:Salivary Proteins and Peptides; D017886:Durapatite