Protection of DmdB from DMSP inhibition by ADP and MMPA. (A) Effect of ADP on RPO_DmdB1. Effect of MMPA on RPO_DmdB2 (B), RL_DmdB1 (C), and RL_DmdB2 (D). Relative activity expressed as a percentage of the total activity in the absence of DMSP. Specific activities in units mg−1 of protein defined as 100% were as follows: RPO_DmdB1, 14 ± 2; RPO_DmdB2, 13 ± 2; RL_DmdB1, 18 ± 3; and RL_DmdB2, 10 ± 3. Errors are ±SE from three replicates.