Molecular mechanism of NAD(P)H -cyclic electron flow

NAD(P)H-循环电子流的分子机制

• 批准号: 04454014
• 负责人: ASADA Kozi
• 金额: $ 3.97万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04454014/
• 关键词: Cyanobacteria; Synechocystis PCC6803; Cyclic elctron flow; NAD(P)H dehydrogenase; P700; Chlorophyll fluorescence; Synechocystis PCC 6803; C4植物

1. Electron donation from stromal components to P700^+ via the intersystem chain was demonstrated in spinach chloroplasts and the pool size of electrons that can be donated to P700^+ was estimated to be in the range of 12 and 28 electrons per p700 under aerobic conditions.2. Electron flow to the intersystem chain from stromal components and cyclic elctron flow in maize were estimated by monitoring redox changes of P700 and chlorophyll fluorescence. Storomal pool size of electrons that can be donated to P700^+ was much larger in maize than in c3 plants, giving a maximum value of 225 elctrons per P700.3. Using cyanobacteria, Synechococcus and Synechocystis, it has been demonstrated that electron donation from cyclic and respiratory flows to the photosynthetic intersystem chain is mediated by pyridine nucleotide dehydrogenase (NDH), which is analogous to mitochondrial complex I.The NDH in cyanobacteria mediates not only NADPH- dependent cyclic flow but also ferredoxin-dependent one.

1.在菠菜叶绿体中证实了基质成分通过系统间链向P700^+提供电子，在有氧条件下，可以向P700^+提供的电子池大小估计为每个p700 12至28个电子。通过监测P700和叶绿素荧光的氧化还原变化，估算了玉米基质组分向系统间链的电子流和循环电子流。在玉米植株中，可以提供给P700^+的电子的风暴池大小比c3植株中的大得多，每个P700 ^+的最大电子数为225个。利用蓝细菌、聚球藻和集胞藻，已经证明从循环流和呼吸流到光合系统间链的电子捐赠是由吡啶核苷酸脱氢酶（NDH）介导的，其类似于线粒体复合物I。蓝细菌中的NDH不仅介导NADPH依赖的循环流，而且介导铁氧还蛋白依赖的循环流。

项目成果

K.Asada: "Electron flow to the intersystem chain from stromal Components and Cyclic electron flow in maize Chloroplasts as detected in intact leaves by redox change of P700 and Chlorophyll fluorescence." Plant & Cell Physiology. 34. 39-50 (1993)

K.Asada：“通过 P700 和叶绿素荧光的氧化还原变化在完整叶子中检测到从基质成分到系统间链的电子流和玉米叶绿体中的循环电子流。”

H.Mi: "Electron donation from cyclic and respiratory flows to the photosynthetic intersystem chain is mediated by pyridine nicleotide dehydrogenase in the cyanobacterium synechocystis PCC 6803." Plant Cell Physiol. 33. 1233-1237 (1992)

H.Mi：“循环和呼吸流向光合系统间链提供的电子是由蓝藻集胞藻 PCC 6803 中的吡啶核苷酸脱氢酶介导的。”

K.Asada: "Pool size of electrons that can be donated to P700^+, as determined in intact leaves : donation to P700^+ from stromal components via the intersystem chain." Plant Cell Physiol. 33. 927-932 (1992)

K.Asada：“可以捐赠给 P700^ 的电子池大小，在完整的叶子中确定：通过系统间链从基质成分捐赠给 P700^。”

K.Asada: "Electron flow to the intersystem chain from stromal components and cyclic electron flow in maize chloroplasts as detected in intact leaves by redox change of P700 and chlorophyll fluorescrence." Plant Cell Physiol. 34. 39-50 (1993)

K.Asada：“通过 P700 的氧化还原变化和叶绿素荧光在完整叶子中检测到从基质成分到系统间链的电子流和玉米叶绿体中的循环电子流。”

H.Mi: "Donation of electrons from cytosolic components to the intersystem chain in the cyanobacterium synechococcus sp.PCC 7002 as determined by the reduction of P700^+." Plant & Cell Physiology. 33. 1099-1105 (1992)

H.Mi：“通过 P700^ 的还原确定蓝藻聚球藻 sp.PCC 7002 中胞浆成分向系统间链的电子捐赠。”