Ecological study on marine luminous bacteria possessing proteorhodopsin

前视紫红质（PR）是一种吸收光能并具有质子泵功能的膜蛋白。由此建立的质子梯度使细胞能够合成ATP，从而用作有效的能量合成组分。这是2000年首次报道的。从那时起，有估计，近一半的原核生物存在于上层水体中的海洋可能具有PR。然而，到目前为止，只有大约10个分离物已被报道具有PR，这使得任何进一步的生理调查困难。本课题组成功分离出60多株菌株，并在光照下直接测定了质子泵活性。此外，通过进一步的假设，我们首次成功地估计了PR对海洋光能吸收的贡献。在我们使用分离株进行研究后，PR的研究正在扩大。

Proteorhodopsin (PR) is a membrane protein that absorbs light energy and functions as proton pump. The proton gradient thus established enables the cells to synthesize ATP, thus serves as efficient energy synthesis component. This was first reported in 2000. Since then there have been estimated that nearly half of prokaryotes present in the upper water column in the ocean may possess PR. However, so far only about 10 isolates had been reported to possess PR, that makes any further physiological investigations difficult. Our group succeeded to isolate more than 60 strains and directly measure the activity of proton pump under light. In addition, with further assumptions we succeeded to estimate the contribution of PR to light energy absorption to the ocean for the first time. The research on PR is now expanding after our investigation using isolates.