TABLE 1.

Clinical data, IEF of β-lactamases present in K. pneumoniae isolates and E. coli transconjugants, ESBLs identified by DNA sequencing, and typing patterns

Isolate Designation	Date of isolation (day.mo.yr)	Ward	Type of specimen	β-Lactamase pI	ESBL	RAPD pattern	RFLP pattern	EcoRI plasmid restriction pattern
1042/96	26.03.1996	Surgery	Throat swab	7.6 8.2a	SHV-5 type	B	B	B
1289/96	11.04.1996	Surgery	Stool	7.6 8.2	SHV-5 type	C	NDb	B
1027/96	23.03.1996	ICU	Blood	6.0 7.6	TEM-47	A	A1	A1
1099/96	09.04.1996	ICU	Tracheostomy tube	6.0 7.6	TEM-47	A	A2	A1
1294/96	13.04.1996	Hematology	Stool	6.0 7.6	TEM-47	A	A1	A1
1298/96	18.04.1996	Cardiology	Urine	6.0 7.6	TEM-47	A	A1	?c
1590/96	25.04.1996	ICU	Tracheostomy tube	6.0 7.6	TEM-47	A	A1	A1
1592/96	13.05.1996	ICU	Throat swab	6.0 7.6	TEM-47	A	A3	A2
L-267d	18.01.1995d	Łódźd	Throat swab	6.0 7.6d	TEM-47d	Ad	A4	A3

^aUnderlined pI values refer to the pIs for β-lactamases which were also produced by transconjugants. 

^bND, not determined. 

^cThe restriction pattern was not clear; see Fig. 3. 

^dReference 14.