Paracoccus pantotrophus pseudoazurin is an electron donor to cytochrome c peroxidase.
Paracoccus pantotrophus pseudoazurin is an electron donor to cytochrome c peroxidase.
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Paracoccus pantotropicus pseudoazurin 是细胞色素 c 过氧化物酶的电子供体。
DOI：
10.1021/bi0491144
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发表时间：
2004
期刊：
影响因子：
2.9
通讯作者：
G. Pettigrew
中科院分区：
文献类型：
--
作者：
S. R. Pauleta;F. Guerlesquin;C. F. Goodhew;B. Devreese;J. V. Van Beeumen;Alice S. Pereira;I. Moura;G. Pettigrew
假天青基因是从泛养副球菌LMD 52.44中分离出来的，并在异源系统中表达，每升培养物产量为54.3毫克纯蛋白。基因和蛋白质显示与来自P. pantotrophus LMD 82.5的那些相同。重新评价蛋白的消光系数，发现在590 nm处为3.00 mM（-1）cm（-1）。据证实，氧化的蛋白质是在一个弱的单体/二聚体平衡，是离子强度依赖性。的pseudoazurin被证明是一个高度活跃的电子供体细胞色素c过氧化物酶，活性显示出与静电相互作用的离子强度依赖性。pseudoazurin具有非常大的偶极矩，其矢量位于推定的电子转移位点His 81，并且在广泛的蓝铜蛋白中在该位置是保守的。过氧化物酶与假天青蛋白的结合导致与His 81面上的残基相关的一组NMR共振的扰动，包括赖氨酸残基的环。这些赖氨酸与刚好从边缘向后的酸性残基相关联，其共振也受到与过氧化物酶结合的影响。我们建议，这些酸性残基温和的赖氨酸的静电影响，因此确保特定的电荷相互作用不形成跨界面与过氧化物酶。
The gene for pseudoazurin was isolated from Paracoccus pantotrophus LMD 52.44 and expressed in a heterologous system with a yield of 54.3 mg of pure protein per liter of culture. The gene and protein were shown to be identical to those from P. pantotrophus LMD 82.5. The extinction coefficient of the protein was re-evaluated and was found to be 3.00 mM(-1) cm(-1) at 590 nm. It was confirmed that the oxidized protein is in a weak monomer/dimer equilibrium that is ionic-strength-dependent. The pseudoazurin was shown to be a highly active electron donor to cytochrome c peroxidase, and activity showed an ionic strength dependence consistent with an electrostatic interaction. The pseudoazurin has a very large dipole moment, the vector of which is positioned at the putative electron-transfer site, His81, and is conserved in this position across a wide range of blue copper proteins. Binding of the peroxidase to pseudoazurin causes perturbation of a set of NMR resonances associated with residues on the His81 face, including a ring of lysine residues. These lysines are associated with acidic residues just back from the rim, the resonances of which are also affected by binding to the peroxidase. We propose that these acidic residues moderate the electrostatic influence of the lysines and so ensure that specific charge interactions do not form across the interface with the peroxidase.
DOI：
10.1093/protein/8.2.153
发表时间：
1995-02-01
期刊：
PROTEIN ENGINEERING
影响因子：
--
作者：
KUKIMOTO, M;NISHIYAMA, M;BEPPU, T
通讯作者：
BEPPU, T