FIG. 5.

Effects of temperature and pH on the activities of P. furiosus aminoacylase. The assay mixture contained aminoacylase (0.64 mg/ml) and N-acetyl-l-methionine (30 mM) in 50 mM bis-Tris, pH 6.5. For the effects of pH, the following buffers (each at 50 mM) were used at the indicated pHs: MES (morpholineethanesulfonic acid), pHs 5.5 and 6.0; bis-Tris, pH 6.5; MOPS, pH 7.0; EPPS (N-2-hydroxyethylpiperazine-N′-3-propanesulfonic acid), pH 8.4; CHES [2-(N-cyclohexylamino)ethanesulfonic acid], pH 8.6; CAPS, pHs 10, 10.5, and 11.0. For effects of temperature, the buffer used was 50 mM bis-Tris, pH 6.5. A 100% activity level corresponds to 200 U/mg.