Cloning, expression, and characterization of a nitric oxide synthase protein from Deinococcus radiodurans
Cloning, expression, and characterization of a nitric oxide synthase protein from Deinococcus radiodurans
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DOI：
10.1073/pnas.012470099
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发表时间：
2002-01-08
影响因子：
11.1
通讯作者：
Stuehr, DJ
中科院分区：
文献类型：
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作者：
Adak, S;Bilwes, AM;Stuehr, DJ
我们克隆、表达并鉴定了耐辐射奇球菌血红素蛋白。抗辐射剂NO合成酶，deiNOS），其序列与哺乳动物NO合成酶（NOSoxys）的加氧酶结构域具有34%的同一性。deiNOS是二聚体，结合底物Arg和辅因子四氢生物蝶呤，并且具有正常的血红素环境，尽管其缺失在NOSoxy中结合Zn 2+和四氢生物蝶呤并帮助形成活性二聚体的N-末端结构。deiNOS血红素接受来自哺乳动物NOS还原酶的电子，并以达到或超过NOSoxy的速率产生NO。活性需要结合四氢生物蝶呤或四氢叶酸，并与形成和消失的一个典型的血红素二氧催化中间体。因此，细菌NOS样蛋白与哺乳动物NOS惊人的相似，拓宽了我们对NO生物化学和功能的认识。
We cloned, expressed, and characterized a hemeprotein from Deinococcus radiodurans (D. radiodurans NO synthase, deiNOS) whose sequence is 34% identical to the oxygenase domain of mammalian NO synthases (NOSoxys). deiNOS was dimeric, bound substrate Arg and cofactor tetrahydrobiopterin, and had a normal heme environment, despite its missing N-terminal structures that in NOSoxy bind Zn2+ and tetrahydrobiopterin and help form an active dimer. The deiNOS heme accepted electrons from a mammalian NOS reductase and generated NO at rates that met or exceeded NOSoxy. Activity required bound tetrahydrobiopterin or tetrahydrofolate and was linked to formation and disappearance of a typical heme-dioxy catalytic intermediate. Thus, bacterial NOS-like proteins are surprisingly similar to mammalian NOSs and broaden our perspective of NO biochemistry and function.