Table 5. Substrate specificity of CatB.

K_m and V_max are indicated as means±S.D. for five determinations. k_cat values were calculated on the basis of the molecular mass of 44 kDa.

Substrate	Km (μM)	Vmax (units·mg−1)	kcat (min−1)	kcat/Km (min−1·μM−1)
cis,cis-Muconate	660±70	390±30	17000±1000	26
2-Methyl-cis,cis-muconate	380±70	8.5±1.4	330±60	1.1
3-Methyl-cis,cis-muconate	310±20	24±2	1100±100	3.1
2-Chloro-cis,cis-muconate	300±60	6.0±2.5	260±110	1.4
3-Chloro-cis,cis-muconate		(<0.01)*
2-Fluoro-cis,cis-muconate		(<0.01)*

* Detection limit for specific activity under the experimental conditions.