摘要
电喷雾质谱(ESI-MS)在研究蛋白质与小分子相互作用方面有着重要应用,然而,添加剂的加入会直接影响ESI-MS分析。目前,二甲基亚砜(DMSO)对质谱分析蛋白质-小分子相互作用的影响尚不明确。本文探究了DMSO对淫羊藿苷、芦丁、柚皮苷、野黄芩苷与溶菌酶复合物的质谱分析影响。发现DMSO不仅影响溶菌酶复合物的表观结合常数和电荷态,还在一定程度上增加了溶菌酶-黄酮复合物的表观亲和力。与不添加DMSO相比,DMSO加入量较低时,复合物的电荷态降低;DMSO加入量略高时,复合物的电荷态升高,且高于未加DMSO时的电荷态。研究表明,DMSO可以用于稳定ESI-MS中的溶菌酶-黄酮复合物,但应控制DMSO用量。
As the secondary metabolites of plants,flavonoids are very important active ingredients in natural medicinal plants and have been proved to possess the extensive biological activities.It has been reported that flavonoids can bind to plasma proteins.Lysozyme is a globular protein and can interact with many small molecules for therapeutic applications.Therefore,the studies of interactions between flavonoids and proteins are not only helpful for understanding of the biological action of small natural organic molecules,but also are beneficial for the development of novel drug candidates.Native electrospray ionization mass spectrometry has been widely applied in the studies of the interactions of proteins and small molecules.During the electrospray ionization(ESI)analysis,some organic solvents are often used as a cosolvent.However,it is not clear for the effects of addition of some organic solvents on the ESI analysis of protein-ligand complexes.The solvent dimethyl sulfoxide(DMSO)is one of cosolvents.There are few studies on the effect of DMSO on protein-small molecule interactions by electrospray mass spectrometry(ESI-MS).Here,the effects of DMSO on the ESI-MS analysis of four lysozyme-flavonoids of icariin,rutin,naringin and scutellarin complexes were investigated.The stable,labile and non-specific binding protein complexes with small molecule ligands were determined by ESI-MS,respectively.It was found that the content of DMSO affects the apparent binding constants of lysozyme and small molecule ligand complexes.The low amounts of DMSO lead to increase the apparent affinity of the labile lysozyme-flavonoid complexes to some extent.It also can stabilize the lysozyme complex with N,N',N''-triacetylchitotriose even under the high capillary temperature.The addition of DMSO cannot lead to the non-specific binding of lysozyme complex with maltose.In addition,the content of DMSO also affects the charge states of the lysozyme complexes.Compared with the sample without DMSO,the charge states of the complex initially decreas
作者
杜杨
赵凤娇
崔勐
DU Yang;ZHAO Feng-jiao;CUI Meng(Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;University of Science and Technology of China,Hefei 230026,China)
出处
《质谱学报》
EI
CAS
CSCD
北大核心
2024年第6期823-831,I0004,共10页
Journal of Chinese Mass Spectrometry Society
