Department of Biological and Environmental Sciences, University of Gothenburg, Box 461, 405 30 Gothenburg, Sweden.
FEBS Lett. 2013 Jul 11;587(14):2083-9. doi: 10.1016/j.febslet.2013.05.046. Epub 2013 May 31.
Oxygenic photosynthetic organisms use sunlight energy to oxidize water to molecular oxygen. This process is mediated by the photosystem II complex at the lumenal side of the thylakoid membrane. Most research efforts have been dedicated to understanding the mechanism behind the unique water oxidation reactions, whereas the delivery pathways for water molecules into the thylakoid lumen have not yet been studied. The most common mechanisms for water transport are simple diffusion and diffusion facilitated by specialized channel proteins named aquaporins. Calculations using published data for plant chloroplasts indicate that aquaporins are not necessary to sustain water supply into the thylakoid lumen at steady state photosynthetic rates. Yet, arguments for their presence in the plant thylakoid membrane and beneficial action are presented.
需氧光合作用生物利用太阳光能将水氧化为分子氧。该过程由类囊体膜腔侧的光系统 II 复合物介导。大多数研究工作都致力于了解独特的水氧化反应背后的机制，而水分子进入类囊体腔的输送途径尚未得到研究。水运输的最常见机制是简单扩散和由专门的通道蛋白（称为水通道蛋白）促进的扩散。使用已发表的植物叶绿体数据进行的计算表明，在稳态光合作用速率下，水通道蛋白对于维持水向类囊体腔的供应不是必需的。然而，仍有人提出它们在植物类囊体膜中的存在及其有益作用的论点。
