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

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。人们认为溶菌酶通过吸附羟基磷灰石而受到保护，含有这些残基的表面是吸附位点。Lys-13的氢-氘交换时间较长。因此认为在侧链上带正电荷的碱性残基是吸附残基。溶菌酶经磷酸制备后吸附在羟基磷灰石上，吸附亲和力约为3倍，但吸附分子数不变。通过这些实验，我们了解到溶菌酶的正电荷（酰胺基团）吸附在羟基磷灰石的负电荷（磷酸基团）上。另一方面，溶菌酶吸附位点周围存在赖氨酸-1、赖氨酸-5、赖氨酸-14、赖氨酸-128。乙酰化溶菌酶的吸附亲和力较天然溶菌酶弱。由于这些碱性残基侧链的酰胺基团被乙酰化，溶菌酶失去了正电荷。我们了解到Lys-1、Arg-5、Lys-13、Arg-14、Arg-128溶菌酶的酰胺基团吸附在羟基磷灰石的磷酸基团上。吸附等温线实验表明，该吸附类型为langmuir型。因此，各溶菌酶不相互作用，溶菌酶与羟基磷灰石单分子膜吸附。

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.