Probing the effects of cysteine residues on protein adsorption onto gold nanoparticles using wild-type and mutated GB3 proteins.
Probing the effects of cysteine residues on protein adsorption onto gold nanoparticles using wild-type and mutated GB3 proteins.
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使用野生型和突变型 GB3 蛋白探讨半胱氨酸残基对金纳米颗粒上蛋白质吸附的影响。
DOI：
10.1021/la402239h
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Dongmao Zhang
中科院分区：
文献类型：
--
作者：
Kumudu Siriwardana;Ailin Wang;Karthikeshwar Vangala;Nicholas C. Fitzkee;Dongmao Zhang
利用金纳米粒子（AuNP）局域表面等离子体共振（LSPR）结合有机硫醇（OT）置换法研究了半胱氨酸残基在蛋白质结合动力学和稳定性中的作用。GB 3是蛋白G的第三个IgG结合结构域，用于模拟蛋白-金纳米粒子吸附。虽然野生型GB 3（GB 30）不含半胱氨酸残基，但也测试了含有一个（GB 31）和两个（GB 32）半胱氨酸残基的生物工程化GB 3变体。半胱氨酸含量对GB 3与AuNP的结合动力学没有显著影响，并且大多数蛋白质吸附发生在蛋白质/AuNP混合后的前几秒内。然而，GB 3在AuNP表面上对OT置换的稳定性强烈依赖于AuNP/GB 3混合物的半胱氨酸含量和年龄。GB 30覆盖的AuNP可以被OT完全去稳定和聚集，而不管GB 30/AuNP混合物的年龄。GB 31或GB 32与AuNPs长时间孵育可以稳定AuNPs对抗OT吸附诱导的聚集。该研究表明，GB 3/AuNP相互作用涉及多种力，半胱氨酸和AuNP之间的共价结合对于稳定的蛋白质/AuNP复合物是必不可少的。
The role of cysteine residues in the protein binding kinetics and stability on gold nanoparticles (AuNP) was studied using AuNP localized surface plasmon resonance (LSPR) in combination with an organothiol (OT) displacement method. GB3, the third IgG-binding domain of protein G, was used to model protein-AuNP adsorption. While wild-type GB3 (GB30) contains no cysteine residues, bioengineered GB3 variants containing one (GB31) and two (GB32) cysteine residues were also tested. The cysteine content has no significant effect on GB3 binding kinetics with AuNPs, and most protein adsorption occurs within the first few seconds upon protein/AuNP mixing. However, the stability of GB3 on the AuNP surface against OT displacement depends strongly on the cysteine content and the age of the AuNP/GB3 mixture. The GB30 covered AuNPs can be completely destabilized and aggregated by OTs, regardless of the age of the GB30/AuNP mixtures. Long-time incubation of GB31 or GB32 with AuNPs can stabilize AuNPs against the OT adsorption inducted aggregation. This study indicates that multiple forces involved in the GB3/AuNP interaction, and covalent binding between cysteine and AuNP is essential for a stable protein/AuNP complex.
影响因子：
46.2
作者：
Dreaden EC;Alkilany AM;Huang X;Murphy CJ;El-Sayed MA
通讯作者：
El-Sayed MA
影响因子：
15
作者：
Ulmer, TS;Ramirez, BE;Bax, A
通讯作者：
Bax, A