The pH Dependent Cu(II) and Zn(II) Binding Behavior of an Analog Methanobactin Peptide
The pH Dependent Cu(II) and Zn(II) Binding Behavior of an Analog Methanobactin Peptide
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类似甲烷菌素肽的 pH 依赖性 Cu(II) 和 Zn(II) 结合行为
DOI：
10.1255/ejms.1249
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发表时间：
2013
影响因子：
1.3
通讯作者：
L. Angel
中科院分区：
文献类型：
--
作者：
Ramakrishna Sesham;Dong;A. Balaji;Sahithi Cheruku;Chiranjeevi Ravichetti;A. Alshahrani;Maheshbabu Nasani;L. Angel
利用离子迁移率-质谱法研究了具有序列乙酰基-His 1-Cys 2-Gly 3-Pro4-His 5-Cys 6（Mw = 694.79 Da）的类似物甲烷氧化菌素肽（amb）对一系列生物活性金属离子的结合能力的pH依赖性反应性。Cu（II）、Zn（II）和在较小程度上Ni（II）在pH > 6下从1：1摩尔当量amb：金属（II）溶液中观察到与amb形成络合物，表明His的咪唑N（pKa = 6.0）必须发生去质子化以允许金属（II）离子的初始锚定。琥珀色金属（II）的配合物被观察到作为正离子和负离子，虽然Zn（II）的配合物优选形成一个整体的负离子配合物，这是一致的两个硫醇基团的Cys 2和Cys 6参与Zn（II）的协调。然而，Cu（II）的加入总是导致Cys-Cys二硫键在Cu-游离amb和Cu-结合amb中，其排除了与Cu（II）的硫醇盐配位。碰撞截面的测量结果表明，锌（II）和铜（II）的负离子复合物小于正离子复合物，表明锌（II）通过咪唑N的组氨酸和巯基的半胱氨酸结合大多数compounds，而铜（II）通过咪唑N的组氨酸和两个去质子化的N的两个酰胺基团的肽骨架上的compounds。从B3 LYP/LanL 2DZ理论水平的最低能量结构显示，His 5、Cys 2和Cys 6的官能团与Zn（II）配位，而His 1和Cys 2和Gly 3的酰胺氮与Cu（II）配位，产生总体带负电荷的络合物。锌（II）和铜（II）的正离子配合物都显示通过两个咪唑氮的His 1和His 5和无论是Cys 6的骨架羰基的氧或C-末端的氧，分别协调。
The pH dependent reactivity of an analog methanobactin peptide (amb) with the sequence acetyl–His1-Cys2–Gly3–Pro4–His5–Cys6 (Mw = 694.79 Da) was investigated for its binding ability for a series of biologically active metal ions using ion mobility-mass spectrometry. Cu(II), Zn(II) and, to a lesser extent, Ni(II) were observed to form complexes with amb from 1: 1 molar equivalent amb:metal(II) solutions at pH > 6, indicating the deprotonation of the imidazole N of His (pKa = 6.0) must occur to allow the initial anchoring of the metal(II) ion. The amb–metal(II) complexes were observed as both positive and negative ions, although the Zn(II) complexes preferred forming an overall negative ion complex which is consistent with the two thiolate groups of Cys2 and Cys6 being involved in Zn(II) coordination. The Cu(II) addition, however, always resulted in a Cys–Cys disulfide bridge in both Cu-free amb and Cu-bound amb, which excluded thiolate coordination to Cu(II). Collision cross-section measurements showed the Zn(II) and Cu(II) negative ion complexes were smaller than the positive ion complexes, suggesting Zn(II) binds most compactly via the imidazole N of His and the thiolate groups of Cys, whereas Cu(II) binds most compactly via the imidazole N of His and two deprotonated N of two amide groups on the peptide backbone. The lowest energy structures from the B3LYP/LanL2DZ level of theory showed the functional groups of His5, Cys2 and Cys6 coordinated to Zn(II), whereas the His1 and the amide nitrogens of Cys2 and Gly3 coordinated to Cu(II), producing an overall negative charged complex. The positive ion complexes of Zn(II) and Cu(II) were both shown to coordinate via the two imidazole nitrogens of His1 and His5 and either the oxygen of the backbone carbonyl of Cys6 or the oxygen of the C-terminal, respectively.
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从甲基孢子菌素OB3b和甲基囊肿菌株SB2中的甲烷素的比较预测甲烷酰胺是由经过修饰的各种肽前体合成的，以创建一种用于结合和还原铜离子的共同核心。
影响因子：
2.9
作者：
Krentz, Benjamin D.;Mulheron, Heidi J.;Semrau, Jeremy D.;DiSpirito, Alan A.;Bandow, Nathan L.;Haft, Daniel H.;Vuilleumier, Stephane;Murrell, J. Colin;McEllistrem, Marcus T.;Hartsel, Scott C.;Gallagher, Warren H.
通讯作者：
Gallagher, Warren H.
影响因子：
15
作者：
Hakemian, AS;Tinberg, CE;Rosenzweig, AC
通讯作者：
Rosenzweig, AC
影响因子：
4.6
作者：
El Ghazouani, Abdelnasser;Basle, Arnaud;Dennison, Christopher
通讯作者：
Dennison, Christopher
影响因子：
4
作者：
Kenney, Grace E.;Rosenzweig, Amy C.
通讯作者：
Rosenzweig, Amy C.
影响因子：
15
作者：
Behling, Lee A.;Hartsel, Scott C.;Lewis, David E.;DiSpirito, Alan A.;Choi, Dong W.;Masterson, Larry R.;Veglia, Gianluigi;Gallagher, Warren H.
通讯作者：
Gallagher, Warren H.