Analyzing secondary structure of ?2 microglobulin in E.coli with circular dichroism spectrum

Abstract:

Abstract: [Objective] In order to study the structure and function of β2 microglobulin (β2m). [Methods] We sub-cloned the mature peptide of β2m into the p2X plasmid and transformed them to the the Esherichia coli (E. coli) TB1. The recombinant bacteria was induced to be expressed and the expressed fusion protein was detected by SDS-PAGE and western blot. After purifying and cleaving with Factor Xa, we separated the monomer protein β2m from MBP. Finally, we determined the secondary structure of the β2m protein by circular dichroism (CD) spectrum. [Results] The results indicated that MBP-β2m was 52.1 kDa, and the monomer protein β2m was 10.6 kDa. The a-helix, b-sheet, turn, and random coil of the fusion protein showed 0, 45, 8 and 45 amino acids, respectively, detected by CD estimation. [Conclusion] The results concluded that the β2m protein had correct secondary structure and could be used to have further research of peptide binding in vitro.