MALDI-TOF MS和电子光谱技术研究海兔肝铁蛋白亚基电离和释放铁动力学特性  

Desorption/Ionization of Subunit and Kinetics of Iron Release Revealed with Matrix-assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry and Electronic Spectrum in Liver Ferritin of Aplysia

作　　者：黄琳[1] 陈旭[1] 林青[1] 朱斌琳[1] 黄河清[1] 

机构地区：[1]厦门大学生命科学学院细胞生物学与肿瘤细胞工程教育部重点实验室

出　　处：《分析化学》2007年第12期1745-1750,共6页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.30470372);福建省高校创新团队培育计划;厦门大学预研基金(No.xdkjcx20051006)资助

摘　　要：选用肽质量指纹谱(peptide mass fingerprint,PMF)技术鉴定质谱纯海兔肝铁蛋白(liver ferritin ofAplysia,ALF)。来源于基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)仪中的激光和基质芥子酸协同解吸海兔肝铁蛋白(ALF)为带双电荷、单电荷[M+H]+和二聚体的亚基离子,并可供质谱分析。ALF亚基的质荷比m/z分别为9784.03[M+2H]2+、19678.42[M+H]+和39387.80[2M+H]+,其中亚基分子量[M+H]+略小于鲨鱼肝铁蛋白(liver ferritin of shark,SLF)。在弱碱介质(pH8.0)条件下,电子光谱技术研究指出,抗坏血酸以1/2级反应方式参与ALF释放铁全过程,同时又使ALF以一级反应动力学方式释放铁,呈现两种不同的速率。推测这一异常现象可能与ALF含低铁量、亚基调节能力和海兔的进化地位有关。Liver ferritin of Aplysia （ALF） with purity of mass spectrometry has been identified by a technology of peptide mass fingerprint. Both lasers coming from the MALDI-TOF MS and matrix sinapic acid together decomposed ALF into molecular ion of the subunit for MS analysis, showing three molecular ions such as single subunit with double [ M ＋ 2H ] ^2 ＋ and single [ M ＋ H ]^＋ charges, and dimeric subunit with single charge [2M ＋H]^＋. The ratio of mass to charge （m/z） of these ions is divided to be 9784.03,19678.42 and 39387.80, respectively. The molecular weight of ALF was somewhat little than that of liver ferritin in shark （SLF）. In weaken basic medium （pH 8.0）, the experimental results used with electron spectral technology showed that ascorbic acid, as a 1/2 order reaction, reduced the whole iron component within the ferritin core for releasing, which resulted in ALF released the iron as first-order law rather than half-order law, showing two different rates of iron release. The results suggested low iron content and the capacities of subunit regula that these novel phenomena be tightly connected with the tion in ALF, and with evolution level.

关 键 词：基质辅助激光解吸电离飞行时间质谱 亚基解离 释放铁 动力学 进化 

分 类 号：Q51-33[生物学—生物化学]