TABLE 3.

ESBL, AmpC, and inhibitor-resistant β-lactamase types identified and their occurrence in isolates from the participant centers

Enzyme type	pI	No. of enzymes	No. of sequencesa	Sequence variant	Presence in isolate(s) from center no.b
					1	2	3	4	5	6	7	8	9	10	11	12	13
ESBL	8.9	3	3	CTX-M-15						+					+		+
ESBL	8.4	216	110	CTX-M-3	+	+	+	+	+	+	+	+	+	+	+	+	+
ESBL	8.2	44	20	SHV-5 (n = 18)	+	+		+	+			+	+	+	+
ESBL	8.2			SHV-12 (n = 2)										+	+
ESBL	7.6	3	3	SHV-2			+
ESBL	6.0	1	1	TEM-19											+
ESBL	5.4	1	1	TEM-48										+
AmpC	∼9.0	71	24	CMY-12 (n = 4)					+		+				+		+
AmpC	∼9.0			CMY-15 (n = 19)	+	+	+	+	+		+	+	+	+	+	+	+
AmpC	∼9.0			CMY-38 (n = 1)								+
Inhibitor-resistant β-lactamase	7.6	1	1	SHV-49			+
Inhibitor-resistant β-lactamase	5.4	1	1	TEM-32			+
Inhibitor-resistant β-lactamase	5.2	2	2	TEM-30												+
Inhibitor-resistant β-lactamase	5.2			TEM-37			+

^aThe number of sequences determined in the study.

^b+ indicates that a particular β-lactamase was identified.