Identification of iron superoxide dismutase and a copper/zinc superoxide dismutase enzyme activity within the marine cyanobacterium Synechococcus sp WH 7803
Identification of iron superoxide dismutase and a copper/zinc superoxide dismutase enzyme activity within the marine cyanobacterium Synechococcus sp WH 7803
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DOI：
10.1016/0378-1097(96)00096-1
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发表时间：
1996-05-01
影响因子：
2.1
通讯作者：
Carr, NG
中科院分区：
文献类型：
--
作者：
Chadd, HE;Newman, J;Carr, NG
在蓝藻海洋微微浮游生物聚球藻中发现了三种组成形式的超氧化物歧化酶活性。WH 7803采用聚丙烯酰胺凝胶活性染色技术。一种在天然聚丙烯酰胺凝胶上呈阳性的非血红素铁染色的蛋白质，其N末端与大肠杆菌的铁超氧化物歧化酶和锰超氧化物歧化酶相似。通过分析它们对5 mM H_2O_2、2 mM氰化物和2 mM铜螯合剂二乙基二硫代氨基甲酸盐的区分敏感性，表征了三个活性带中每一个的金属修复基团。观察到三种不同的超氧化物歧化酶活性，一种是铁超氧化物歧化酶，一种是铜/锌超氧化物歧化酶，第三种形式尚未鉴定。聚球藻细胞在不含铁的ASW培养液中生长，对铁超氧化物歧化酶的活性没有影响。在没有铜或锌的情况下，培养物的生长导致铜/锌超氧化物歧化酶和未知的超氧化物歧化酶活性的不同变化。
Three constitutive forms of superoxide dismutase activity have been demonstrated in the cyanobacterial marine picoplankter Synechococcus sp. WH 7803 using polyacrylamide gel activity staining techniques. A protein which gave a positive non-haem iron stain on native polyacrylamide gels exhibited N-terminal similarity to both the iron superoxide dismutase and the manganese superoxide dismutase of Escherichia coli. The metal prosthetic group of each of the three activity bands was characterised by analysing their differential sensitivities to 5 mM H2O2, 2 mM cyanide and 2 mM of the copper chelator diethyldithiocarbamate. Three distinct superoxide dismutase activities were observed, an iron superoxide dismutase, a copper/zinc superoxide dismutase and a third form which has not been identified. Growth of Synechococcus cells in ASW medium containing no added iron resulted in no alteration in the activity of the iron superoxide dismutase. Growth of cultures in the absence of copper or zinc resulted in differential changes in the activities of the copper/zinc superoxide dismutase and the unidentified superoxide dismutase.