Brown S B, Houghton J D, Vernon D I
Department of Biochemistry, University of Leeds, U.K.
J Photochem Photobiol B. 1990 Apr 1;5(1):3-23. doi: 10.1016/1011-1344(90)85002-e.
Phycobiliproteins play important roles in photomorphogenesis and photosynthesis. The light-absorbing chromophores of the phycobiliproteins are linear tetrapyrroles (bilins) very similar in structure to the mammalian bile pigments. 5-Aminolaevulinate (5-ALA) is the first committed intermediate in phycobilin synthesis. The biosynthesis of 5-ALA, destined for phycobilins, occurs via the five-carbon pathway, now well established for tetrapyrrole synthesis in plants and distinct from the mammalian pathway. The phycobilins are formed by reduction of biliverdin which results from the synthesis and degradation of haem. This haem is an essential intermediate in the biosynthesis of phycobilins. Phycocyanobilin, the blue-green pigment found in certain algae and cyanobacteria, is formed from biliverdin via phytochromobilin, the chromophore of phytochrome. This leads to the likelihood that phytochromobilin is formed as an end product, or intermediate, in the synthesis of all phycobilins.
藻胆蛋白在光形态建成和光合作用中发挥着重要作用。藻胆蛋白的吸光发色团是线性四吡咯（胆素），其结构与哺乳动物的胆汁色素非常相似。5-氨基乙酰丙酸（5-ALA）是藻胆素合成中的第一个关键中间体。用于藻胆素的5-ALA生物合成通过五碳途径进行，这一途径现已在植物四吡咯合成中得到充分确立，且与哺乳动物途径不同。藻胆素是由血红素合成和降解产生的胆绿素还原形成的。这种血红素是藻胆素生物合成中的必需中间体。藻蓝胆素是在某些藻类和蓝细菌中发现的蓝绿色色素，它通过植物色素的发色团——藻红胆素由胆绿素形成。这使得藻红胆素很可能是所有藻胆素合成的终产物或中间体。
