Multiphasic analyses of the interaction between cariogenic polysaccharide and tooth enamel

致龋多糖与牙釉质相互作用的多相分析

• 批准号: 08672135
• 负责人: OGAWA Kozo
• 金额: $ 1.47万
• 依托单位: Osaka Prefecture University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08672135/
• 关键词: dental caries; Streprococcus sobrinus; hydroxyapatite; cariogenic α-glucan; lactic acid; (1→3)-α-D-glucan; X-ray diffraction analysis; conformational energy calculation; Streptococcus sobrinus; ハイドロオキシアパタイト; 乳酸; カルボキシメチルキチン; エチレングリコールキチン; α-G

It has been known that a bacteria, Streptococcus sobrinus, found in human saliva converts sucrose to a sticky polysaccharide called α-glucan. This glucan called α-glucan is composed of (1→3)-α-linked D-glucose in the backbone sequence on which (1→6)-α-linked D-glucose is attached as a side residue, and it is involved in dental plaque formation by sticking on the surface (tooth enamel composed of hydroxyapatite) of human teeth. In the plaque, the bacteria transforms sucrose to lactic acid which dissolves hydroxyapatite (decalcification of the enamel) and, consequently it causes of dental caries. We have studied to analyze the cause of dental caries by various physicochemical strategies as follows.1. The conformational analyses of α-glucan by using an X-ray diffraction coupled with an energy calculation indicated that the backbone (1→3)-α-D-glucan takes up an extended two-fold helix (a zigzag structure). Some energetically preferable conformations of the glucan were proposed.2. Spectroscopic (infrared, fluorescence and circular dichroism) studies on the interaction between α-glucan and a hydroxyapatite crystal of pseudohexagonal polymorph, which is likened to tooth enamel, did not detect the presence of any strong bond such as hydrogen bonding.3. Examinations of the effects of some caries preventers on the dissolution of hydroxyapatite to lactic acid indicated that two chitin derivatives (carboxymethyl and ethylene glycol chitins) decrease the soubility.

已知在人类唾液中发现的细菌远缘链球菌（Streptococcus sobrinus）将蔗糖转化为称为α-葡聚糖的粘性多糖。这种被称为α-葡聚糖的葡聚糖在主链序列中由（1→3）-α-连接的D-葡萄糖组成，（1→6）-α-连接的D-葡萄糖作为侧残基附着在主链序列上，并且它通过粘附在人牙齿的表面（由羟基磷灰石组成的牙釉质）上而参与牙菌斑的形成。在牙菌斑中，细菌将蔗糖转化为乳酸，乳酸溶解羟基磷灰石（釉质脱钙），因此导致龋齿。本研究通过以下几种物理化学方法分析龋病的病因.利用X射线衍射结合能量计算对α-葡聚糖的构象进行了分析，结果表明，（1→3）-α-D-葡聚糖的主链是一个延伸的双螺旋结构（Z字形结构）。提出了葡聚糖的一些能量优选构象.对α-葡聚糖和假六方晶型羟基磷灰石晶体（类似于牙釉质）之间相互作用的光谱（红外、荧光和圆二色性）研究没有发现任何强键（如氢键）的存在。研究了几种防龋剂对羟基磷灰石在乳酸中溶解的影响，结果表明两种甲壳素衍生物（羧甲基甲壳素和乙二醇甲壳素）降低了羟基磷灰石的溶解度。

项目成果

Ogawa, K., Kawada, J., Yui, T.: "Conformation of chitosan ascorbic acid salt"Advances in Chitin Science (Proceedings of the 3rd International Conference of the European Chitin Society, Potsdam, Germany, Aug. 31 - Sept. 3, 1999). Vol. 4 (in press).

Okawa, K.、Kawada, J.、Yui, T.：“壳聚糖抗坏血酸盐的构象”甲壳素科学进展（欧洲甲壳素学会第三届国际会议论文集，德国波茨坦，8 月 31 日至 9 月 12 日）

T. Yui, K. Nakata, K. Ogawa: "Conformations of Ethylene Glycol Derivatives of Chitin and Chitosan" Bull. Univ. Osaka Pref., Ser. B. 48. 125-129 (1996)

T. Yui、K. Nakata、K. Okawa：“甲壳素和壳聚糖的乙二醇衍生物的构象”公牛。

K.Ogawa et al.: "Chain conformational analysis of beijeran by n-h map calculation" Carbohydr.Res.,. 304. 341-345 (1997)

K.Okawa等人：“通过n-h图计算对beijeran进行链构象分析”CarboHydr.Res.，。

Ogawa, K., Kawada J., Otsuka, T., Mitsugi, M., Yui, T.: "Chitosan ascorbic acid salt""Chitosan per os. from dietary supplement to drug carrier" (R.A.A. Muzzarelli ed.). (in press).

Okawa, K.、Kawada J.、Otsuka, T.、Mitsugi, M.、Yui, T.：“壳聚糖抗坏血酸盐”“口服壳聚糖从膳食补充剂到药物载体”（R.A.A. Muzzarelli 编辑）。

K.Ogawa et al.: "Crystalline Features of Chitosan-L- and D-Lactic Acid Salts" Biosci.Biotech.Biochem.62・4. 700-704 (1998)

K.Okawa等人：“壳聚糖-L-和D-乳酸盐的晶体特征”Biosci.Biotech.Biochem.62・4（1998）。