Sengupta Annesha, Sunder Avinash Vellore, Sohoni Sujata V, Wangikar Pramod P
ACS Synth Biol. 2019 May 17;8(5):1219-1223. doi: 10.1021/acssynbio.9b00066. Epub 2019 Apr 22.
The cyanobacterium Synechococcus elongatus PCC 7942 is a potential photosynthetic cell-factory. In this study, two native promoters from S. elongatus PCC 7942 driving the expression of abundant cyanobacterial proteins phycocyanin (P ) and RuBisCO (P ) were characterized in relation to their sequence features, expression levels, diurnal behavior, and regulation by light and CO, major abiotic factors important for cyanobacterial growth. P was repressed under high light intensity, but cultivation at higher CO concentration was able to recover promoter activity. On the other hand, P was repressed by elevated CO with a negative regulatory region between 300 and 225 bp. Removal of this region flipped the effect of CO with Rbc225 being activated only at high CO concentration, besides leading to the loss of circadian rhythm. The results from this study on promoter features and regulation will help expand the repertoire of tools for pathway engineering in cyanobacteria.
聚球藻属的细长聚球藻PCC 7942是一种潜在的光合细胞工厂。在本研究中，对来自细长聚球藻PCC 7942的两个天然启动子进行了表征，它们驱动丰富的蓝藻蛋白藻蓝蛋白（P ）和核酮糖-1,5-二磷酸羧化酶/加氧酶（P ）的表达，涉及它们的序列特征、表达水平、昼夜行为以及受光和CO₂（对蓝藻生长重要的主要非生物因素）的调控。P 在高光强度下受到抑制，但在较高CO₂浓度下培养能够恢复启动子活性。另一方面，P 被升高的CO₂抑制，在300至225 bp之间存在一个负调控区域。去除该区域会改变CO₂的作用，Rbc225仅在高CO₂浓度下被激活，此外还会导致昼夜节律丧失。这项关于启动子特征和调控的研究结果将有助于扩展蓝藻途径工程工具的种类。
