中文摘要：

变形菌视紫红质（proteorhodopsin,PR）是一类吸光色素膜蛋白,它是由7个跨膜ɑ-螺旋（A～G）组成的视蛋白（opsins）与色素视黄醛（retinal）通过共价键结合而形成。PR广泛存在于海洋和淡水水域的微生物中,是一种质子泵型的视紫红质,可在光的驱动下将质子从细胞质泵到胞质间隙,从而在细胞内外产生质子梯度,形成的化学势能被用于合成ATP、物质的跨膜运输以及驱动鞭毛运动等方面。据估算含PR的细菌在海洋水域中约占总细菌的13%,而每个含PR的细胞中的PR分子数约为2.5×104个。对PR功能的研究表明PR具有增强其宿主菌抵抗外界不良环境的能力;而对于PR三维结构的研究对PR的作用机理及其功能的研究将有更进一步的推动作用。

英文摘要：

Proteorhodopsin（PR） is a seven-transmembrane protein which uses retinal as its chromophore.This protein was found widely distributed in the ocean and some freshwater around world since the first report about it ten years ago.PR is a light driven proton pump which generates proton motive force by translocating protons across the cell inner membrane.Calculation shows that PR-bearing bacterium is one of the numerically richest microorganisms on the Earth,accounting for 13% of the total in sea surface water,and with averaged 2.5×104 PR molecules per cell.Recent studies show that proteorhodopsin phototrophy confers a fitness advantage to marine bacteria during periods of resource deprivation at the ocean＇s surface.