TABLE 4.

Substrate specificity of the muconate cycloisomerase from A. “calcoaceticus” ADP1^a

Substrate	Km (μM)	kcat (min−1)	kcat/Km (min−1 μM−1)
cis,cis-Muconate	130 ± 10	3,700 ± 200	29
2-Chloro-cis,cis-muconate	290 ± 90	17 ± 4	0.06
3-Chloro-cis,cis-muconate		(<10)b
2,4-Dichloro-cis,cis-muconate		(<10)b
3-Fluoro-cis,cis-muconate	100 ± 10	2,600 ± 200	24
2-Methyl-cis,cis-muconate	490 ± 120	4,700 ± 1,000	9.7
3-Methyl-cis,cis-muconate	99 ± 7	1,800 ± 100	18

^aThe K_m and k_cat values were determined as described in Materials and Methods. Standard deviations were calculated with the Enzfitter program. The measurements were determined with an enzyme preparation described previously (57). 

^bThe activity at a substrate concentration of 0.1 mM was below the detection limit for this measurement. Consequently, k_cat, K_m, and k_cat/K_m values could not be determined.