FIG. 4.

(A) Purification of the N^ECC-N^TMX-H₆ precursor from hN2 after expression in bacteria. M, molecular mass standards; E, the N^ECC-N^TMX-H₆ uncleaved precursor after elution from nickel-NTA beads. (B) Denaturing HPLC chromatograms of the hN2 precursor (top) and N^ECC-N^TMX heterodimer (bottom). Samples of both the precursor and intact heterodimer (after cleavage with recombinant furin) were recovered in a single peak after gel filtration. An aliquot of the peak from each sample was further analyzed by denaturing reversed-phase HPLC chromatography using a C₁₈ column. The peaks corresponding to the precursor and each of the subunits are indicated.