The Distribution of Cytotoxic Necrotizing Factors (CNF-1, CNF-2, CNF-3) and Cytolethal Distending Toxins (CDT-1, CDT-2, CDT-3, CDT-4) in Escherichia coli Isolates Isolated from Extraintestinal Infections and the Determination of their Phylogenetic Relationship by PFGE

Table 2

Thermal cycles for eleven primers are used in this study.

No	Step	uidA	CNFs	CDTS	chuA, yjA, tspe4.c2
1	Initial denaturation	94°C/5 min	94°C/3 min	94°C/5 min	94°C/5 min
2	Denaturation	94°C/30 sec	94°C/1 min	94°C/1 min	94°C/30 sec
	Annealing	63°C/30 sec	60°C/1 min	60°C/1 min	60°C/30 sec
	Extension	72°C/1.5 min	72°C/1 min	72°C/1 min	72°C/1.5 min
3	Final extension	72°C/5 min	72°C/7 min	72°C/10 min	72°C/5 min