Figure 5.

Counteracting effect of H₂S on PX-12 binding to sulfhydryl residues in Trx. (A,B) Enhancement of Trx activity by H₂S. rTrx (2 μg) was treated with 250 μM PX-12 and 1 mM NaHS for 2 h and assayed for sulfhydryl groups as described in Materials and Methods. To confirm the equal loading of rTrx, the membrane was probed for Trx using anti-Trx antibody. Note the obvious increased MAL-labeled Trx after NaHS treatment in comparison with PX-12 alone (A). Densitometric analysis of the blot was shown in (B). Data shown are mean ± SE, (n = 3; ^**P < 0.01 vs. untreated control; ^##P < 0.01 vs. PX-12 alone).