多拷贝pucBA基因在沼泽红假单胞菌光合生长中的作用

Role of Multiple Copy pucBA Genes in Phototrophic Growth of Rhodopseudomonas palustris

选择沼泽红假单胞菌CGA009菌株,采用基因敲除方法,依次对菌株中的5对pucBA基因进行敲除,以探求不同pucBA基因对菌株光合生长、光谱表型和光合色素质量浓度的影响。结果表明:不同pucBA基因的表达量与菌株光合生长速率和光合色素合成量呈正相关关系;高光下pucBA_(b)和pucBA_(a)基因对菌株生长发挥主要作用,低光下pucBA_(b),pucBA_(d)和pucBA_(a)基因对菌株生长起主要作用;敲除pucBA_(d)基因可导致pucBA_(b)基因高效表达,敲除pucBA c基因可导致LH1-RC合成量提高,表明某个pucBA基因的敲除对其他光合基因表达具有补偿作用。

Selecting Rhodopseudomonas palustris CGA009 strain,gene knockout method was used to sequentially knock out five pairs of pucBA genes in the strain in order to explore the effects of different pucBA genes on photosynthetic growth,spectral phenotype and photosynthetic pigment mass concentration of the strain.The results showed that the expression levels of different pucBA genes were positively correlated with the photosynthetic growth rate and photosynthetic pigment synthesis of the strain.The pucBA_(b)and pucBA_(a)genes played a major role in strain growth under high light conditions,while the pucBA_(b),pucBA_(d)and pucBA_(a)genes played a major role in strain growth under low light conditions.Knocking out the pucBA_(d)gene could lead to efficient expression of pucBA_(b)gene,while knocking out the pucBA c gene could increase LH1-RC synthesis,indicating that the knockout of a certain pucBA gene had a compensatory effect on the expression of other photosynthetic genes.