TABLE 4.

Stability and affinity for various types of β-lactamases

β-Lactamase (original host)	J-110,441		Hydrolysis (relative %)a
	Hydrolysis (relative %)a	Kib(μM)	Compound 3a	Compound 7a	Imipenem
Metallo-β-lactamases
IMP-1 (P. aeruginosa)	1	0.0037	2	2	100
CcrA (B. fragilis)	3	0.23	22	18	100
L1 (S. maltophilia)	6	1.00	61	40	100
Type II (B. cereus)	8	0.83	7	63	100
Serine β-lactamases
Group 2b,d class A (E. coli)	<1	2.54	2	NTc	<1
Group 1,d class C (E. cloacae)	<1	0.037	<1	NT	<1

^aTaking the hydrolysis rates of imipenem and cephaloridine as 100% for metallo- and serine β-lactamases, respectively. 

^bImipenem and cephaloridine were used as the substrates for metallo- and serine β-lactamases, respectively. 

^cNT, not tested. 

^dBush’s classification (3).