glycob.oxfordjournals.org
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\nHiroki Nakagawa3,4, Yoichiro Hama4, Toshihisa Sumi4, Su-Chen Li3, Karol Maskos3,7, Kittiwan Kalayanamitra2,5, Shuji Mizumoto5,6, Kazuyuki Sugahara5,6 and Yu-Teh Li1,3<\/p>\n
3 Department of Biochemistry, Tulane University Health Sciences Center School of Medicine, New Orleans, LA 70112
\n4 Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan
\n5 Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, Kobe 658-8558, Japan
\n6 Laboratory of Proteoglycan Signaling and Therapeutics, Faculty of Advanced Life Science, Hokkaido University, Frontier Research Center for Post-Genomic Science and Technology, Kita 21-jo, Nishi 11-choume, Kita-ku, Sapporo 001-0021, Japan
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\n1 To whom correspondence should be addressed; Tel.: (504)-988-2451; Fax: (504)-988-2739; e-mail: yli1@tulane.edu<\/p>\n
Received on June 19, 2014; revised on September 27, 2014; accepted on September 29, 2014<\/p>\n
Despite their wide occurrence, proteoglycans (PGs) have never been isolated from the saliva of higher animals. We found that the Collocalia glycoproteins isolated from edible birds’-nests (the dried forms of regurgitated saliva of male Collocalia swiftlets) were rich in a PG containing nonsulfated chondroitin glycosaminoglycans (GAGs). We have devised a method to isolate a PG from the water extract of the white nest built by Aerodramus fuciphagus (white nest swiftlets) with a yield of 2-mg PG per gram nest. This PG contained 83% of carbohydrates, of which 79% were GalNAc and GlcUA (D-glucuronic acid) in an equimolar ratio. By using chondroitin AC lyase, the structure of GAGs in this PG was established to be chondroitin ( 4GlcUA\u00df1 3GalNAc\u00df1 )n chains. The average molecular mass of the chondroitin chain was estimated to be 49\u00a0kDa by gel filtration. We have isolated a linkage region hexasaccharide, HexUA1 3GalNAc\u00df1 4GlcUA\u00df1 3Gal\u00df1 3Gal\u00df1 4Xyl, from this PG by chondroitinase ABC digestion to show that the GAGs in this PG are also linked to the core protein through the common tetrasaccharide linker, GlcUA\u00df1 3Gal\u00df1 3Gal\u00df1 4Xyl, found in various PGs. As water was not effective in extracting uronic acid-containing glycoconjugates from the black nest built by black nest swiftlets (A. maximus), we used 4\u00a0M guanidium chloride and anion-exchange chromatography in the presence of urea to extract and isolate about 30\u00a0mg of a chondroitin PG preparation from 10\u00a0g of the desialylated black nest. As the biological significance of chondroitin is still not well understood, bird’s nest should become a convenient source for preparing this unique GAG to study its biological functions.<\/p>\n
Key words: chondroitin \/ proteoglycan \/ glycosaminoglycan \/ bird’s nest \/ saliva<\/p>\n
2 Present address: Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand<\/p>\n
7 Deceased, March 29, 2004.<\/p>\n
None declared.<\/p>\n","protected":false},"excerpt":{"rendered":"
glycob.oxfordjournals.org Hiroki Nakagawa3,4, Yoichiro Hama4, Toshihisa Sumi4, Su-Chen Li3, Karol Maskos3,7, Kittiwan Kalayanamitra2,5, Shuji Mizumoto5,6, Kazuyuki Sugahara5,6 and Yu-Teh Li1,3 3 Department of Biochemistry, Tulane University Health Sciences Center School of Medicine, New Orleans, LA 70112 4 Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan 5 Department of Biochemistry, Kobe Pharmaceutical University, Higashinada-ku, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[413],"tags":[],"yoast_head":"\n