Reduction of Photosystem I Reaction Center in DrgA Mutant of the Cyanobacterium Synechocystis sp. PCC 6803 Lacking Soluble NAD(P)H:Quinone Oxidoreductase
Reduction of Photosystem I Reaction Center in DrgA Mutant of the Cyanobacterium Synechocystis sp. PCC 6803 Lacking Soluble NAD(P)H:Quinone Oxidoreductase
复制标题
蓝藻集胞藻 DrgA 突变体中光系统 I 反应中心的减少。
DOI：
10.1023/b:biry.0000026203.23785.43
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
F. V. Yaminsky
中科院分区：
文献类型：
--
作者：
I. Elanskaya;K. Timofeev;V. G. Grivennikova;G. Kuznetsova;L. N. Davletshina;E. Lukashev;F. V. Yaminsky
蓝藻聚胞藻的光自养培养细胞。PCC6803野生型和Ins2突变体在编码可溶性NAD(P)H：Quone氧化还原酶(NQR)的drgA基因上插入后，在白光脉冲氧化后的光诱导放氧速率和光系统I反应中心(P700+)还原方面没有差异。在DCMU存在下，突变细胞的P700+还原速率低于野生型细胞。暗饥饿24小时后呼吸底物的耗尽导致DrgA突变细胞的P700+还原速率比野生型细胞更显著。在光自养生长的DrgA突变体中，外源葡萄糖产生的电子对P700+的还原速度慢于野生型细胞。DrgA基因的突变不影响集胞藻的生长能力。PCC6803细胞在异养条件下氧化葡萄糖，并且不损害蓝藻类囊体膜上依赖于NDH-1的、鱼藤酮抑制的从NADPH到P700+的电子传递。在光自养生长条件下，DrgA突变细胞的NADPH-脱氢酶活性低于野生型细胞的30%。这些结果表明，由drgA基因编码的NQR可能参与了蓝藻胞质NADPH氧化的调节，为磷酸戊糖循环中的葡萄糖氧化提供NADP+。
Photoautotrophically grown cells of the cyanobacteriumSynechocystissp. PCC 6803 wild type and the Ins2 mutant carrying an insertion in thedrgAgene encoding soluble NAD(P)H:quinone oxidoreductase (NQR) did not differ in the rate of light-induced oxygen evolution and Photosystem I reaction center (P700+) reduction after its oxidation with a white light pulse. In the presence of DCMU, the rate of P700+reduction was lower in mutant cells than in wild type cells. Depletion of respiratory substrates after 24 h dark-starvation caused more potent decrease in the rate of P700+reduction in DrgA mutant cells than in wild type cells. The reduction of P700+by electrons derived from exogenous glucose was slower in photoautotrophically grown DrgA mutant than in wild type cells. The mutation in thedrgAgene did not impair the ability ofSynechocystissp. PCC 6803 cells to oxidize glucose under heterotrophic conditions and did not impair the NDH-1-dependent, rotenone-inhibited electron transfer from NADPH to P700+in thylakoid membranes of the cyanobacterium. Under photoautotrophic growth conditions, NADPH-dehydrogenase activity in DrgA mutant cells was less than 30% from the level observed in wild type cells. The results suggest that NQR, encoded by thedrgAgene, might participate in the regulation of cytoplasmic NADPH oxidation, supplying NADP+for glucose oxidation in the pentose phosphate cycle of cyanobacteria.
影响因子：
4.9
作者：
H. Mi;T. Endo;U. Schreiber;T. Ogawa;K. Asada
通讯作者：
H. Mi;T. Endo;U. Schreiber;T. Ogawa;K. Asada
影响因子：
4.9
作者：
H. Mi;T. Endo;U. Schreiber;T. Ogawa;K. Asada
通讯作者：
H. Mi;T. Endo;U. Schreiber;T. Ogawa;K. Asada