FIGURE 1.

TSG-6/HC2 transfers HCs from bikunin proteins to the CS of free bikunin. Bikunin containing the CS chain was purified, fluorescently labeled, and incubated with TSG-6 alone (lane 4 and 8) or TSG-6, and respectively, IαI (lane 1 and 5), Pre-α-inhibitor (PαI) (lane 2 and 6), or HC2·bikunin (lane 3 and 7). The samples were incubated either in the presence of MgCl₂ (lane 1–4) or in the presence of EDTA (lane 5–8). Afterward, the samples were subjected to reducing SDS-PAGE, and subsequently, the gel was imaged using a fluorescent scanner. The result demonstrated that TSG-6/HC2 transfers HCs from HC2·bikunin and from IαI to the CS chain originating from bikunin by a divalent cation-dependent mechanism.