Hydrophobic Porphyrin Assemblies with Oxygen-Transporting Capability

血红蛋白是一种含有铁卟啉作为氧结合位点的蛋白质，并从空气中选择性地摄取和携带分子氧。通过对精确合成的卟啉进行疏水性组装，可以实现在不同于血红蛋白的条件下工作的新型载氧材料。将疏水性铁卟啉与木聚糖酶杂交，中村先前报道了木聚糖酶的温度稳定性。在高温下，卟啉-木聚糖酶复合物的红色水溶液仍能与铁卟啉发生可逆的氧结合。90℃。由于木聚糖酶的配位位点与催化活性位点不同，其催化活性不受干扰。这种利用疏水相互作用的简单策略将适用于其他主客体组合，这可能提供一类全新的人工血红素蛋白结构。 ...更多信息 通过三重或四重氢键与四羟基杯[4]芳烃形成双链体，在卟啉平面上提供封端结构，这伴随着阻转异构体的自发平衡移动。这是第一个通过氢键键合的卟啉-杯[4]芳烃双链体的例子，并得到了厚度为80 nm的四苯基卟啉钴聚合物薄膜。均匀的红色膜在室温和高压下可逆地结合和释放分子氧。氧气渗透系数大，并急剧增加，随着氧气上游压力的降低。在上下游差为1cmHg时，氧选择透过率大于150。这表明固定在固体膜中的钴卟啉促进了膜中的氧传输。在相同的条件下，将压缩空气施加到上游，以在下游提供高于900%的氧浓度。这表明弱的氧结合亲和力对于有效的氧促进运输是优选的。少

Hemoglobin is a protein containing iron porphyrin as an oxygen-binding site and uptakes and carries molecular oxygen from air selectively. Designing assemblies focused on hydrophobicity of the precisely synthesized porphyrin enables to realize novel oxygen-carrying materials which work under conditions that different from that of hemoglobin.The hydrophobic iron porphyrin was hybridized with the xylanase which Nakamura have previously reported its stability against temperature. The red-colored aqueous solution of porphyrin-xylanase hybrid displayed a reversible oxygen-binding to the iron porphyrin even at high temperature at ca. 90℃. The catalytic activity as the xylanase was not interfered because the coordination site is different from that of the catalytic activity. This simple strategy using hydrophobic interactions will be applicable to the other host-guest combinations, which could afford a totally new class of artificial hemoprotein architectures.Meso-tetra(2-pyridyl) porphyrin f … More orms a duplex with tetrahydroxylcalix[4]arene via triplicate or quadruple hydrogen bonds, to provide a capping structure on the porphyrin plane, which was accompanied by the spontaneous equilibrium shift of the atropisomers. This was the first example of a hydrogen-bonded porphyrin-calix[4]arene duplex.Polymeric cobalt tetraphenylporphyrin thin membrane was obtained with nanometer thickness (80nm from SEM). The homogeneous red membrane reversibly binds and releases molecular oxygen at room temperature under high pressure. Oxygen permeability coefficient was large and steeply increased with decrease in oxygen upstream pressure. Oxygen permselectivity at 1cmHg difference between upstream and downstream was over 150. This indicates that the fixed cobalt porphyrin in the solid membrane facilitated oxygen transport in the membrane. Compressed air was applied to the upstream in the same condition to give the oxygen concentration above 900% at downstream. This indicates weak oxygen-binding affinity is preferable for the efficient oxygen facilitated transport. Less