摘要
用不锈钢／电沉积紫膜薄膜／含水胶（电介质）／钢型菌紫质光电池研究了作用于Ｎ－端表面（紫膜外表面）的钾、镁、镧离子对菌紫质光电响应的影响．在所测条件下光电极性均与质子泵方向一致．光电压幅值是离子浓度依赖性的，对钾、镁、镧离子均存在极大值浓度，它们之间有数量级的差异；依赖性曲线趋势和极大值浓度均各自分别与溶液中菌紫质的质子泵效率对阳离子浓度的这种依赖性相一致．不过，光电响应对作用于Ｃ－端表面的这些离子不存在上述的浓度依赖性．上述的两种依赖性成相关性说明：电沉积紫膜薄膜中菌紫质的光电响应主要来自质子泵运而非非质子离子的贡献；存在一合适的离子浓度使菌紫质的光电响应有极大值．用质子泵结构域模型和扩散双电层理论对这种依赖性进行的讨论认为：金属阳离子的结合与屏蔽两种效应可以解释这种依赖性．
he photovoltaic response, of the bacteriorhodopsinbased sandwich photocell with type of stainless steel/purple membrane film by electrodeposition/Agarose gel/copper, the extraplasmic side faced towards the gel, to continuous light was studied. The polarities of the responses are the same as that of the proton punp under the experimental conditions. The responses were dependence of cationic concentrations in the gel at the extraplasmic side, but the dependence differed from that at the cytoplasmic side. The maximum occured in the plot of the voltage vs the concentration at =75 mmol/L、 [Mg2+]=1.5 mmol/L, and [La3+]=1.5 μmol/L, respectively, in the gel at the extraplasmic side. The shape of the curve of the dependence of voltage on K+、 Mg2+ or La3+ in the gel was similar to that of the quantum efficiency of the proton pump in suspension, respectively. This implication of the relativity was ① the contribution of the photoelectric response of bacteriorhodopsin in the films is due to the proton pump rather than nonproton cations; ② there is a concentration of cation, at which the voltage arrived maxium. The dependence was discussed in the form of the proton domain model and the theory of the diffuse double layer, it may be interpreted by the bindingand screeningeffect of metal cations.
出处
《感光科学与光化学》
CSCD
1997年第3期217-222,共6页
Photographic Science and Photochemistry
基金
中国科学院基金
国家教委分子与生物分子电子学开放实验室资助
关键词
菌紫质
光电响应
质子泵
电沉积紫膜薄膜
bacteriorhodopsin
photoelectric response dependence of ions proton pump
purple membrane film by electrodeposition
