Characteristics of H and L Subunits with Mass Spectrometry, Electrophoresis and Transmission Electron Microscopy in Liver Ferritin of Dasyatis Akajei

Liver ferritin of Dasyatis akajei (DALF) with mass purity was prepared in batch. Transmission electron microscopy(TEM) was used to determine the molecular sizes of DALF, protein shell, and iron core, respectively. Experimental results of SDS-PAGE method indicated that DALF consisted of two different subunit types, H and L subunits. Moreover, both types of H and L subunits and their homology were further proofed by peptide mass fingerprinting(PMF). The redox reagents such as natural read, thionine, and methyl viologen, and the acidity at pH 1.5 have no abilities for making the interaction intensity of both H-L and L-L subunits reduced to form the ions of L subunit for mass analysis with MALDI-TOF MS, respectively. However, using a combined approach of increasing laser intensity and decreasing the matrix pH synchronously, MALDI-TOF mass spectrometric method has the ability for analyzing molecular weights both H and L subunits in DALF, It indicated that the interaction intensity of H-L and L-L subunit types was higher than that of H-H subunit type in DALF.