Agronomy College, Chengdu Campus, Sichuan Agricultural University, Chengdu 611130, China.
J Biosci. 2011 Dec;36(5):951-6. doi: 10.1007/s12038-011-9161-7.
The plastid terminal oxidase (PTOX) is a plastoquinol oxidase localized in the plastids of plants. It is able to transfer electrons from plastoquinone (PQ) to molecular oxygen with the formation of water. Recent studies have suggested that PTOX is beneficial for plants under environmental stresses, since it is involved in the synthesis of photoprotective carotenoids and chlororespiration, which could potentially protect the chloroplast electron transport chain (ETC) from over-reduction. The absence of PTOX in plants usually results in photo-bleached variegated leaves and impaired adaptation to environment alteration. Although PTOX level and activity has been found to increase under a wide range of stress conditions, the functions of plant PTOX in stress responses are still disputed now. In this paper, the possible physiological roles of PTOX in plant stress responses are discussed based on the recent progress.
质体末端氧化酶（PTOX）是一种定位于植物质体中的质体醌氧化酶。它能够将电子从质醌（PQ）转移到分子氧，形成水。最近的研究表明，PTOX 有益于植物在环境胁迫下的生长，因为它参与了光保护类胡萝卜素和光呼吸的合成，这可能潜在地保护叶绿体电子传递链（ETC）免受过度还原。植物中缺乏 PTOX 通常会导致光漂白斑驳的叶片和对环境变化的适应能力受损。尽管已经发现 PTOX 的水平和活性在广泛的胁迫条件下增加，但植物 PTOX 在应激反应中的功能仍存在争议。在本文中，根据最近的进展，讨论了 PTOX 在植物应激反应中的可能生理作用。
