Singh Shailendra P, Kumari Sunita, Rastogi Rajesh P, Singh Kanchan L, Sinha Rajeshwar P
Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi 221 005, India.
Indian J Exp Biol. 2008 Jan;46(1):7-17.
Continuous depletion of the stratospheric ozone layer has resulted in an increase in ultraviolet-B (UV-B; 280-315 nm) radiation on the earth's surface which inhibits photochemical and photobiological processes. However, certain photosynthetic organisms have evolved mechanisms to counteract the toxicity of ultraviolet or high photosynthetically active radiation by synthesizing the UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin besides the repair of UV-induced damage of DNA and accumulation of carotenoids and detoxifying enzymes or radical quenchers and antioxidants. Chemical structure of various MAAs, their possible biochemical routes of synthesis and role as photoprotective compounds in various organisms are discussed.
平流层臭氧层的持续损耗导致地球表面紫外线B（UV-B；280 - 315纳米）辐射增加，这抑制了光化学和光生物学过程。然而，某些光合生物已经进化出机制来对抗紫外线或高光合成有效辐射的毒性，除了修复紫外线诱导的DNA损伤以及积累类胡萝卜素、解毒酶或自由基淬灭剂和抗氧化剂外，还通过合成吸收紫外线/屏蔽化合物，如类菌孢素氨基酸（MAAs）和藻青素。本文讨论了各种MAAs的化学结构、它们可能的生物合成途径以及在各种生物体中作为光保护化合物的作用。
