A, amino acid sequence of 1-lip E2p containing LDh. The C-terminally derived E2p proteins were created by introducing a TAA stop codon at certain position, leading to E2p(1–96) (LDh) comprising LDh (residues 1–85, in red) and partially linker (in black); E2p(1–164) and E2p(1–190) (both didomains), comprising LDh, PSBD (residues 108–164, in blue); linkers of a different length (in black); and E2pCD (residues 177–425, in violet). The additional 20 amino acid residues from vector including His6 tag at the N-terminal end are also presented (in red). B, amino acid sequence of 3-lip E2p with corrected residue 295 (Ala → Val) by LC-MS/MS and DNA sequencing. LD1, residues 1–78; LD2, residues 105–181; LD3, residues 282–313. The E2p(1–394) tetradomain comprised LD1, LD2, LD3, PSBD, and linkers (residues 1–394), and the E2pCD was residues 381–629.