Chlorophyll a oxygenase (CAO) is involved in chlorophyll b formation from chlorophyll a
Chlorophyll a oxygenase (CAO) is involved in chlorophyll b formation from chlorophyll a
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DOI：
10.1073/pnas.95.21.12719
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发表时间：
1998-10-13
影响因子：
11.1
通讯作者：
Okada, K
中科院分区：
文献类型：
--
作者：
Tanaka, A;Ito, H;Okada, K
叶绿素B是陆生植物、绿色藻类和原绿藻中普遍存在的辅助色素。它的生物合成在适应各种光环境中起着关键作用。我们分离了6个叶绿素b-少突变体的插入突变体，通过使用硝酸还原酶或乙酰氨基琥珀酸裂解酶基因作为标签，并检查突变体基因组的重排。我们发现，在所有突变体的核基因组的重叠区域被删除，这编码的蛋白质的序列是类似的甲基单加氧酶。该编码序列还含有[2Fe-2S] Rieske中心和单核铁的推定结合结构域。结果表明，叶绿素a加氧酶参与叶绿素B的形成。讨论了叶绿素B形成的反应机理。
Chlorophyll b is an ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. Its biosynthesis plays a key role in the adaptation to various light environments. We isolated six chlorophyll b-less mutants by insertional mutagenesis by using the nitrate reductase or argininosuccinate lyase genes as tags and examined the rearrangement of mutant genomes. We found that an overlapping region of a nuclear genome was deleted in all mutants and that this encodes a protein whose sequence is similar to those of methyl monooxygenases. This coding sequence also contains putative binding domains for a [2Fe-2S] Rieske center and for a mononuclear iron. The results demonstrate that a chlorophyll a oxygenase is involved in chlorophyll b formation. The reaction mechanism of chlorophyll b formation is discussed.