Table 1.

Comparison of kinetic parameters for 3 with those for methionine and methionine analogs 4 and 5

Analog	kcat/Km (s−1⋅μM−1)	kcat/Km (rel)*	Relative protein yield (%)†
Met	5.47  × 10−1	1	100
3	1.42  × 10−3	1/390	100
4	1.16  × 10−3	1/500	100
5	5.22  × 10−4	1/1,050	57

^*Relative to k_cat/K_m for Met. 

^† Yield of mDHFR relative to that obtained from Met-supplemented cultures of E. coli strain CAG18491/pQE15/pREP4 (35 mg/liter).