Preparation of Catalytic Antibodies toward the Synthesis of Sequential Polypeptides

制备单克隆抗体，分别针对含偶氮苯基和芘基的非天然氨基酸肽。抗偶氮苯抗体仅结合反式偶氮苯基团，并在其光异构为顺式形式时释放。偶氮苯基的光异构化发生在结合位点内。利用这一独特的性质，尝试了氧化还原酶的光开关反应。当偶氮苯单元与NAD^+衍生物连接时，后者在醇脱氢酶和脱氢酶的偶联氧化还原酶反应中表现出正常的中介活性。当加入抗偶氮苯抗体时，在黑暗条件下，中介活性被完全抑制，但在紫外光照射下，中介活性恢复。这个光循环可以重复多次。光控抗原抗体反应是在含有偶氮苯基的单分子膜上进行的，单分子膜浇铸在云母的平面上。用原子力显微镜（AFM）技术直接观察结合在单分子膜表面的抗体。抗体数量随半抗原含量的增加而增加，表明该结合对半抗原基团具有特异性。半抗原抗体反应的光控也在单分子膜表面实现。抗pyrenyl抗体结合多种pyrenyl衍生物，包括L-1-pyrenylalanine。但它不结合d -1-芘丙氨酸。这种独特的性质将应用于非天然氨基酸的光学分辨。详细研究了与抗芘基抗体结合的芘基的芘基荧光。发现处于激发态的芘基留在结合位点内并发出荧光。

Monoclonal antibodies were raised against peptides containing nonnatural amino acids carring azobenzene group and pyrenyl group, respectively. The anti-azobenzene antibody bound only trans azobenzene group and released it when it was photoisomerized to the cis form. The photoisomerization of bound azobenzene group was found to take place inside the binding site. By using this unique property, a photoswitching of redox enzyme reaction was attempted. When an azobenzene unit was linked to an NAD^+-derivative, the latter showed normal mediation activity in a coupled redox enzyme reaction of alcohol dehydrogenase and diaphorase. When the anti-azobenzene antibody was added to the enzyme system, the mediation activity was completely suppressed in the dark, but the mediation activity recovered when the system was irradiated with UV light. The photocycle could be repeated many times.The photocontrolled antigen-antibody reaction was carried out on a monolayr containing azobenzene groups cast on a flat surface of mica. The antibodies bound on the monolayr surface were directly observed with atomic-force microscopy (AFM) technique. The number of antibody increased with increasing the hapten content, indicating that the binding is specific to the hapten groups. Photocontrol of the hapten-antibody reaction was also achieved on the monolayr surface.The anti-pyrenyl antibody bound a variety of pyrenyl derivatives including L-1-pyrenylalanine. But it did not bind D-1-pyrenylalanine. The unique property will be applied to optical resolution of nonnatural amino acids. The pyrenyl fluorescence of pyrenyl group bound to the anti-pyrenyl antibody was studied in detail. It was found that the pyrenyl group in the excited state remains inside the binding site and fluoresces.