α-Elastin coacervate as a protein liquid membrane: Effect of pH on transmembrane potential responses

✍ Scribed by K. Kaibara; K. Sakai; K. Okamoto; Y. Uemura; K. Miyakawa; M. Kondo

• Book ID: 102761866
• Publisher: Wiley (John Wiley & Sons)
• Year: 1992
• Tongue: English
• Weight: 759 KB
• Volume: 32
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360320906

✦ Synopsis

A protein liquid membrane composed of coacervated a-elastin, a chemical fragmentation product of the biological elastic fiber protein, functioned as an amphoteric liquid ion-exchange membrane. Ionic permselectivities of the a-elastin coacervate membrane to a series of metal chlorides were investigated for the concentration-cell systems by the ordinary electrochemical measurements. Effects of p H on the transmembrane potential responses for NaC1, CaC12, and MgClz systems were examined. Only in the Ca2+-containing system did potential responses stay at constant levels against the pH changes, whereas in the other systems, increasing pH caused potential changes, indicating a improvement of cationic permselectivity across the a-elastin coacervate membrane. It was suggested that the characteristic Ca2+ transport mechanisms across the a-elastin coacervate membrane are related in some way to the polypeptide backbone interactions specific and selective to Ca2+ ions.