Test of non-aggressive organism adjustment for biomaterial and the clinical application

生物材料非攻击性生物调节试验及临床应用

• 批准号: 06671959
• 负责人: TERADA Yoshihiro
• 金额: $ 1.41万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06671959/
• 关键词: NMR; H-D exchange; Hydroxyapatite; Lysozyme; adsorption; 固体表面; 2次元NMR

Hydrogen-deuterium exchange time was longer with Leu-8, Ala-9, Ala-10, Ala-11, Lys-13 in lysozyme which absorbed onto hydroxyapatite. It is thougt lysozyme is protected by absorbing onto hydroxyapatite, and the surface containing these residues is adsorbing site. Hydrogen-deuterium exchange time of Lys-13 was longer than others. So it is thought basic residues which have positive charges in lateral chain is adsorbing residue.When lysozyme absorbed onto hydroxyapatite after preparing it by phosphoric acid, the adsorbing affinity was approximately 3 times but the adsorbing molecular number didn't change.By these experiment we understood that the positive charge (amide group) of lysozyme adsorbs on the negative charge (phosphoric acid group) of hydroxyapatite.On the other hand, Lys-1, Arg-5, Arg-14, Arg-128 existed around adsorbing site of lysozyme. The adsorbing affinity of acetylating lysozyme was weaker than native lysozyme. Because the amide group of lateral chain of those basic residue was acetylated and lysozyme lost the positive charge.We understood that the amide group of Lys-1, Arg-5, Lys-13, Arg-14, Arg-128 lysozyme adsorbed on the phosphoric acid group of hydroxyapatite. And this adsorbing type was Langmuir-type by adsorbing isotherm experiment. Fortheremore each of lysozyme didnot have interaction, and lysozyme absorbs onto hydroxyapatite with monolayr.

溶菌酶中的Leu-8、Ala-9、Ala-10、Ala-11、Lys-13吸附在羟基磷灰石上，氢氘交换时间较长。认为溶菌酶是通过吸附在羟基磷灰石上而得到保护的，含有这些残留物的表面是吸附位点。Lys-13的氢-氘交换时间较长。因此认为侧链带正电荷的碱性残基是吸附残基，磷酸制备后的羟基磷灰石吸附溶菌酶，吸附亲和力约为3倍，但吸附分子数不变，说明侧链带正电荷的碱性残基是吸附残基溶菌酶的酰胺基吸附在负电荷上而在溶菌酶吸附位点周围则存在着Lys-1、Arg-5、Arg-14、Arg-128等氨基酸残基。乙酰化溶菌酶的吸附能力比天然溶菌酶弱。由于这些碱性残基侧链的酰胺基被乙酰化，使溶菌酶失去正电荷，我们认为Lys-1、Arg-5、Lys-13、Arg-14、Arg-128溶菌酶的酰胺基吸附在羟基磷灰石的磷酸基上。吸附等温线实验表明该吸附类型为Langmuir型。溶菌酶与羟基磷灰石之间不存在相互作用，溶菌酶以单层吸附在羟基磷灰石上。