Sheridan Kevin J, Duncan Elizabeth J, Eaton-Rye Julian J, Summerfield Tina C
Department of Botany, University of Otago, Dunedin, New Zealand.
Department of Biochemistry, University of Otago, Dunedin, New Zealand.
Photosynth Res. 2020 Aug;145(2):111-128. doi: 10.1007/s11120-020-00762-7. Epub 2020 Jun 18.
The psbA gene family in cyanobacteria encodes different forms of the D1 protein that is part of the Photosystem II reaction centre. We have identified a phylogenetically distinct D1 group that is intermediate between previously identified G3-D1 and G4-D1 proteins (Cardona et al. Mol Biol Evol 32:1310-1328, 2015). This new group contained two subgroups: D1, which was frequently in the genomes of heterocystous cyanobacteria and D1 that was part of the far-red light photoacclimation gene cluster of cyanobacteria. In addition, we have identified subgroups within G3, the micro-aerobically expressed D1 protein. There are amino acid changes associated with each of the subgroups that might affect the function of Photosystem II. We show a phylogenetically broad range of cyanobacteria have these D1 types, as well as the genes encoding the G2 protein and chlorophyll f synthase. We suggest identification of additional D1 isoforms and the presence of multiple D1 isoforms in phylogenetically diverse cyanobacteria supports the role of these proteins in conferring a selective advantage under specific conditions.
蓝藻中的psbA基因家族编码不同形式的D1蛋白，该蛋白是光系统II反应中心的一部分。我们已经鉴定出一个系统发育上不同的D1组，它介于先前鉴定的G3-D1和G4-D1蛋白之间（Cardona等人，《分子生物学与进化》32:1310 - 1328，2015）。这个新组包含两个亚组：经常存在于异形胞蓝藻基因组中的D1，以及作为蓝藻远红光光适应基因簇一部分的D1。此外，我们还在G3（微需氧条件下表达的D1蛋白）中鉴定出了亚组。与每个亚组相关的氨基酸变化可能会影响光系统II的功能。我们表明，在系统发育范围广泛的蓝藻中存在这些D1类型，以及编码G2蛋白和叶绿素f合酶的基因。我们认为，鉴定出更多的D1同工型以及在系统发育多样的蓝藻中存在多种D1同工型，支持了这些蛋白在特定条件下赋予选择性优势的作用。
