Table 1.

Inhibition constants for the interaction of immucillins with E. coli MTAN and human MTAP^a and the ratio of the two values in order to provide a qualitative indication of the therapeutic window for the treatment of an E. coli infection.

Compound	Ki for E. coli MTAN (nM)	Ki for Human MTAP (nM)	Ki Human MTAP / Ki E. coli MTAN
	0.84 ± 0.06	*3.2 ± 0.2	4
	*0.009 ± 0.001	0.8 ± 0.1	89
	*0.047 ± 0.009	*1.7 ± 0.3	36
	0.7 ±0.1	18 ± 2	26
	0.063 ± 0.005	*2.1 ± 0.3	33
	*0.013 ± 0.001	*2.6 ± 0.4	200
	0.059 ± 0.008	14 ± 2	237
	*0.03 ± 0.002	8 ± 1	267
	0.65 ± 0.03	3.2 ± 0.4	4.9
	0.35 ± 0.03	3.0 ± 0.3	8.6
	0.39 ± 0.02	31 ± 3	80
	2.0 ± 0.2	59 ± 8	30
	*0.064 + 0.005	-b	selective
	*0.054 ± 0.005	71 ± 5	1314
	0.31 ± 0.02	*0.7 ± 0.2	2
	0.0034 ± 0.0009	*0.55 ± 0.07	162
	1.8 ± 0.3	34 ± 3	19

^aK_i is the dissociation constant for the first step in E + I ↔ EI ↔ EI^*, the two-step binding characteristic of slow-onset tight-binding inhibition.

^*indicates slow onset binding and is theoverall dissociation constant for E + I ↔ EI*. In cases where no * is shown then slow-onset inhibition was not observed.

^bindicates that no inhibition was observed at 2.5 μM.