水通道蛋白 Z(AQPZ)具有水选择专一性强、渗透性高等特点，可广泛用于制备水回收和脱盐的生物仿生膜。定点突变詹氏甲烷球菌(Methanococcus jannaschii)的酪氨酸-tRNA合成酶(tyrosyl-tRNA synthetase, TyrRS)，使其可催化非天然氨基酸(丙炔氧基-L-苯丙氨酸(p-propargyloxyphenylalanine,pPpa))合成对应氨酰tRNA。将上述转运系统与大肠杆菌无细胞体系结合，在 AQPZ 的特定位点引入了 pPpa 将改性的 AQPZ（P-AQPZ）重构到1,2-二油酰基磷脂酰胆碱(1,2-dioleoyl-sn-glycero-3-phosphocholine, DOPC)，经停留光谱分析，其水渗透因子Pf值为3.42´10-4 m×s-1，是AQPZ的2.78倍。用截留反渗透装置分析发现P-AQPZ仿生膜的水通量高于AQPZ仿生膜并可保持较高的截盐率。%Aquaporin Z (AQPZ) is a typical orthodox aquaporin with high water permeability and selectivity, and it could be widely used in biomimetic membrane for water recycling and desalination. Site-specific mutagenesis of tyrosyl-tRNAsynthetase (TyrRS) from Methanococcus jannaschii was processed to synthesize corresponding amino acyl tRNA from unnatural amino acids (p-propargyloxyphenylalanine,pPpa). pPpa was then site-specifically incorporated into AQPZ by combining the above transfer system with a Escherichia coli cell-free system, and the modified AQPZ was reconstituted into 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) liposomes and analyzed by stopped-flow spectroscopy. The results show that the osmotic water permeability value (Pf) of the modified AQPZ proteoliposomes is 3.42´10-4 m×s-1, which is 2.78 times higher than that of the AQPZ proteoliposomes. The layer-by-layer membrane embedded with the modified AQPZ demonstrates higher water flux than the AQPZ embedded membrane with same high salt rejection rates.
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