The visible difference spectra, M412 yield and M412 decay lifetime in blue membrane (bM) to purple membrane (pM)transition induced by Na+, Mg2+ and Tb3+ metal ions were characterized. The transition ability from bM to pM induced by Tb3+ , Mg2+ and Na+ has distinguished difference, their concentration ratio at the midpoint of ion-induced absorhance changes is 1: 2. 5 : 650. Meanwhile, the curve of absorbance changes at 540 nm is similar to that of M412 yield changes in bM to pM transition. The M412 decay lifetime of regenerative pM induced by Tb3+ was prolonged remarkably when more Tb3+ was added.However, for the other two ions, additional ions have no effects on its lifetime. These results suggest that diverse valence metal ions exist in different binding ways from pM.%研究了Na+,Mg2+和Tb3+三种不同价金属离子介导的的蓝膜到紫膜转换的可见差光谱,M412产率和Mt412衰减寿命.结果表明,他们的转换能力有很大差别,三种不同离子介导的吸收变化的中间点的浓度比Na+:Mg2+:Tb3+为1:2.5:650,同时,在蓝膜到紫膜转换中,其540nm的吸收变化的曲线与M412产率变化的曲线相符合.当更多的Tb3+加入时,Tb3+介导的重组紫膜的M412衰减寿命有明显延长.而对另两种离子,加入更多时不延长Mt12衰减寿命.这些结果表明,不同价金属离子与紫膜有不同结合方式.
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