Enterobacter cloacae strain 4118 was isolated from pus from a groin wound in California, United States. This strain is resistant to penicillins, carbapenems, and pipercillin-tazobactam and it is sensitive to aztreonam. The depositor states that this is the first serine carbapenemase described in the United States: the class A IMI-1, co-produced with TEM-1.