Table 1.

Details of PCR primers, PCR conditions and amplicon sizes used in this study for the detection of virulence and regulatory genes.

Target gene	Direction	Primer sequence (5ʹ- 3ʹ)	Amplicon size (bp)	PCR condition			Reference
				Denaturation	Annealing	Extension
ctxA	F	CTC AGA CGG GAT TTG TTA GGC ACG	301	94 °C 1 min	55 °C, 45 sec	72 °C 1 min	(Shirai et al., 1991)
	R	TCT ATC TCT GTA GCC CCT ATT ACG
ctxB	F	GGT TGC TTC TCA TCA TCG AAC CAC	460	94 °C 1 min	58 °C, 1 min	72 °C 1 min	(Olsvik et al., 1993)
	R	GAT ACA CAT AAT AGA ATT AAG GAT
tcpA-class	F	CAC GAT AAG AAA ACC GGT CAA GAG	620	94 °C 1 min	58 °C, 45 sec	72 °C 1 min	(Rivera et al., 2001)
	R	TTA CCA AAT GCA ACG CCG AAT G -3′
tcpA-El Tor	F	CAC GAT AAG AAA ACC GGT CAA GAG	453	94 °C 1 min	55 °C, 45 sec	72 °C 1 min	(Rivera et al., 2001)
	R	CGA AAG CAC CTT CTT TCA CAC GTT G
stn	F	GAG AAA CCT ATT CAT TGC	216	94 °C 1 min	54 °C, 30 sec	72 °C 45 sec	(Vicente et al., 1997)
	R	GCA AGC TGG ATT GCA AC
Zot	F	TCG CTT AAC GAT GGC GCG TTT T	947	94 °C 1 min	58 °C, 45 sec	72 °C 1 min	(Rivera et al., 2001)
	R	AAC CCC GTT TCA CTT CTA CCC A
ompU	F	ACG CTG ACG GAA TCA ACC AAA G	869	94 °C 1 min	55 °C, 1 min	72 °C 1 min	(Rivera et al., 2001)
	R	GCG GAA GTT TGG CTT GAA GTA G
ace	F	TAA GGA TGT GCT TAT GAT GGA CAC CC	316	94 °C 1 min	55 °C, 30 sec	72 °C 45 sec	(Shi et al., 1998)
	R	CGT GAT GAA TAA AGA TAC TCA TAG G
toxR	F	CCT TCG ATC CCC TAA GCA ATA C	779	94 °C 1 min	58 °C, 1 min	72 °C 1 min	(Rivera et al., 2001)
	R	AGG GTT AGC AAC GAT GCG TAA G
toxT	F	TTG CTT GGT TAG TTA TGA GAT	581	94 °C 1 min	56 °C, 45 sec	72 °C 1 min	(Kondo and Ajawatanawong, 2009)
	R	TTG CAA ACC CAG ACT GAT AT
vpsR	F	TAGAGCACGGCTTACCGCCA	649	94 °C 1 min	63 °C 1 min	72 °C 1 min	This study
	R	GCCAGCCAACGGACTTGCTT
crp	F	CGCGGGTGAGAAAGCGGAAA	286	94 °C 1 min	63 °C 1 min	72 °C 1 min	This study
	R	CACTTGCAGACGACGAGCCA
hapR	F	GGTACTATACGCGCCACCAA	191	94 °C 1 min	60 °C 1 min	72 °C 1 min	This study
	R	GAACCACGCAGCAATCCAAC

F, forward; R, Reverse.