Dielectric barrier discharge plasma treatment affects stability, metal ion coordination, and enzyme activity of bacterial superoxide dismutases
Dielectric barrier discharge plasma treatment affects stability, metal ion coordination, and enzyme activity of bacterial superoxide dismutases
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DOI：
10.1002/ppap.202000019
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发表时间：
2020-05-27
影响因子：
3.5
通讯作者：
Bandow, Julia E.
中科院分区：
文献类型：
--
作者：
Krewing, Marco;Jung, Christoph K.;Bandow, Julia E.
要在分子水平上理解大气压等离子体对生物样品的影响，就需要了解对蛋白质的影响。超氧化物歧化酶是在氧化应激条件下使超氧化物解毒的酶，在细菌血浆抵抗中起着关键作用。研究了介质阻挡放电(DBD)处理对纯化的超氧化物歧化酶SODA和SODB的影响，结果表明，DBD处理使蛋白质迅速降解，10min后仅有8%的蛋白质残留。氢氧化钠对金属辅因子Mn2+的亲和力降低。质谱学结合耦合簇计算揭示了活性中心氨基酸残基的修饰可以解释金属亲和力的降低和导致活性丧失的配位几何构型的扭曲。
A molecular-level understanding of the effects of atmospheric-pressure plasma on biological samples requires knowledge of the effects on proteins. Superoxide dismutases, which detoxify superoxide under oxidative stress conditions, play a key role in bacterial plasma resistance. Investigation of the impact of dielectric barrier discharge (DBD) treatment on purified superoxide dismutases SodA and SodB of Escherichia coli showed that DBD treatment caused a rapid protein degradation, with only 8% of protein remaining after 10 min. The affinity of SodA for the metal cofactor Mn2+ was reduced. Mass spectrometry, in conjunction with coupled-cluster calculations, revealed that modifications of amino acid residues in the active site can explain the decreased metal affinity and a distortion of the coordination geometry responsible for the activity loss.