The use of photochemical reaction centers to convert light energy into chemical energy, chlorophototrophy, occurs in organisms belonging to only five eubacterial phyla: Cyanobacteria, Proteobacteria, Chlorobi, Chloroflexi, and Firmicutes. All chlorophototrophs synthesize two types of pigments: (a) chlorophylls and bacteriochlorophylls, which function in both light harvesting and uniquely in photochemistry; and (b) carotenoids, which function primarily as photoprotective pigments but can also participate in light harvesting. Although hundreds of carotenoids have been identified, only 12 types of chlorophylls (Chl a, b, d; divinyl-Chl a and b; and 8(1)-hydroxy-Chl a) and bacteriochlorophylls (BChl a, b, c, d, e, and g) are currently known to occur in bacteria. This review summarizes recent progress in the identification of genes and enzymes in the biosynthetic pathways leading to Chls and BChls, the essential tetrapyrrole cofactors of photosynthesis, and addresses the mechanisms for generating functional diversity for solar energy capture and conversion in chlorophototrophs.

中文翻译：

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细菌中的叶绿素生物合成：结构和功能多样性的起源。

使用光化学反应中心将光能转换为化学能，即氯光营养素，发生在仅属于五个真细菌门的生物中：蓝细菌，变形细菌，Chlorobi，Chloroflexi和Firmicutes。所有的叶绿素都合成两种类型的色素：（a）叶绿素和细菌叶绿素，它们在光收集和光化学中都具有独特的功能；（b）类胡萝卜素，其主要起光保护性颜料的作用，但也可以参与采光。尽管已鉴定出数百种类胡萝卜素，但只有12种叶绿素（Chl a，b，d；二乙烯基-Chl a和b；以及8（1）-羟基-Chl a）和细菌叶绿素（BChl a，b，c，d目前已知，e和g）在细菌中发生。