Interaction of tannin with human salivary histatins.
The ability of all major human salivary histatins to precipitate condensed tannin was demonstrated, and it was found that histatins 3 and 5 share the same condensed tannin-binding region but less tannin bound to histatin 1. The condensed tannin-binding region of histatin 5 includes both the N- and the C-terminal parts, although more tannin binding occurs in the C-terminal region. Epigallocatechin gallate (EGCG) showed similar binding characteristics as condensed tannin, but much less EGCG was precipitated. Pentagalloyl glucose (PGG) was precipitated equally well by histatins 1, 3, and 5 and bound equally well to the N- and C-terminal regions of histatin 5. In contrast to condensed tannin, cleaving histatin 5 into N- and C-terminal fragments increased their ability to precipitate PGG. Together, these results show a number of differences in the nature of interaction of histatins with condensed tannin, EGCG, and PGG. Most of the condensed tannin-protein complexes remained insoluble under conditions similar to those in the stomach and the small intestine, suggesting that histatins may act as a defense against dietary tannin in humans.
Naurato
N
N
Faculty of Dentistry and Department of Biochemistry, University of Toronto, Canada.
Wong
P
P
Lu
Y
Y
Wroblewski
K
K
Bennick
A
A
D000595:Amino Acid Sequence; D054808:Histatins; D006801:Humans; D047348:Hydrolyzable Tannins / Q000737:chemistry*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D012471:Salivary Proteins and Peptides / Q000737:chemistry*; D000099053:Histidine-Rich Glycoprotein
C068075:HTN3 protein, human; D054808:Histatins; D047348:Hydrolyzable Tannins; D010446:Peptide Fragments; D011506:Proteins; D012471:Salivary Proteins and Peptides; D000099053:Histidine-Rich Glycoprotein