The Growing Genetic and Functional Diversity of Extended Spectrum Beta-Lactamases

Table 1

Various classification schemes and representatives of extended spectrum beta-lactamase enzymes.

Ambler (molecular) class	Bush & Jacoby group (2009)	Substrate/target	Inhibition profile		Member examples
			Clavulanic acid	Tazobactam
A	2a	Penicillins	Yes	No	PC-1
	2b	Penicillins, some of the 1st-generation cephalosporin	Yes	No	TEM-1, TEM-2, SHV-1
	2be	Extended spectrum cephalosporin, monobactam	Yes	No	TEM-3, SHV-2, CTX-M-15, PET-1, VEB-1
	2br	Penicillins	No	No	TEM-30, SHV-10
	2ber	Extended spectrum cephalosporin, monobactam	No	No	TEM-50
	2c	Carbenicillin	Yes	No	PSE-1, CARB-3
	2ce	Carbenicillin, cefepime	Yes	No	RTG-4
	2e	Extended spectrum beta-lactams	Yes	No	CepA
	2f		Changing	No	KPC-2, 1M1-1, SME-1
B	3a	Carbapenems	No	Yes	IMP-1, VIM-1, CcrA, IND-1, NDM-1
	3b	Carbapenems	No	Yes	CphA, Sfh-1
C	1	Cephalosporins	No	No	AmpC, P99, ACT-1, CMY-2, FOX-1, MIR-1
	1e	Cephalosporins	No	Yes	GC1, CMY-37
D	2d	Cloxacillin	Changeable	No	OXA-1, OXA-10,
	2de	Extended spectrum cephalosporin	Changeable	No	OXA-11, OXA-15
	2df	Carbapenems	Variable	No	OXA-23, OXA-48