The overall spectrum of double-CI2 was similar to that of WT-CI2!

In particular, the side chain NH signals of Glu4, Glu7 and Ala56, and
side chain signal of Trp5 were observed at almost the same positions in the spectra of WT-CI2 and Double-CI2. Supporting the occurrence of the native CI2-like strcture for "each domain" of double-CI2.