具羥基磷灰石吸附能力胜肽之設計與合成

Design and Synthesis of Peptide with Hydroxyapatite-binding Affinity

尤識凱(Shih-Kai Yu)

指導教授 ： 陳惠亭

高雄醫學大學/藥學院/藥學研究所/碩士(2010年)

https://doi.org/10.6832/KMU.2010.00099

摘要

羥基磷灰石 (Hydroxyapatite, 簡稱HAP)在人體內是一種含鈣的磷灰石晶體單位體而成為骨骼必要的支撐結構分子，其分子式為Ca10(PO4)6(OH)2。天然界中具有吸附HAP能力之蛋白質共同基團就是具有碳酸根基團 (-COOH)，而此結構基團也是成為化合物及蛋白質作為吸附及螯合鈣離子的重要關鍵。
本論文仿自然界中一個與礦物質結合的特殊蛋白質為Osteocalcin (簡稱OC)之序列中與HAP吸附的結構為本實驗主要研究以及合成動機。其方法利用固相胜肽合成，以 Fmoc為 N端保護基之策略進行所需胜肽序列合成，四條胜肽序列分別為此 H-LEPRREV-NH2 (Peptide-1)、H-DADELAD-NH2 (Peptide-2)、H-DELAD-NH2 (Peptide-3)、Fmoc-DELADA-NH2 (Fmoc-Peptide-4)其產率各別為35%、58%、38%、25%。
由設計之四條胜肽中個別以 CHTTM column分析 retention time及HAP binding assay分析吸附後，依據結果推測得其產物中Peptide-1[H-LEPRREV-NH2]對於HAP的吸附能力大於bovine serum albumin。其由胜肽本身對於CHT管柱材質較具吸附作用之結果，也建立簡易、快速之篩選方法。

關鍵字

羥基磷灰石 ； 骨鈣素

並列摘要

Hydroxyapatite (HAP) is compose of calcareous apatite crystal unit, Ca10(PO4)6(OH)2, that becomes the skeleton of essential structural support in human. To compare hydroxyapatite binding protein and the calcium binding affinity compound ex: Tetracycline, biphosphate e.t.c. In nature, the common carboxyl group (-COOH) functional group is the common structure for calcium binding and adsorption.
Herein, we mimic a particular protein named Osteocalcin (OC) which can bind with mineral in the nature; As a result, the partial sequence in change of HAP adsorption was studied and synthesized. The designed peptides were synthesized through Fmoc strategy by solid phase peptide synthesis (SPPS). The four peptides sequences are H-LEPRREV-NH2(Peptide-1), H-DADELAD-NH2(Peptide-2), H-DELAD-NH2(Peptide-3) and Fmoc-DELADA-NH2(Fmoc-Peptide-4) respectively. Their reaction yield 35%, 58%, 38%, 25%, individually.
The retention time of four designed peptides were measured through CHTTM column adsorption. Among these peptides, peptides-1 presents stronger affinity on HAP over bovine serum albumin (BSA). Meanwhile, to a convenient and high speed screen platform is established based on CHT chromatography.

並列關鍵字

Hydroxyapatite ； Osteocalcin

參考文獻

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