TABLE 1.

Primers used in PCR amplification experiments

Gene or inte-gron primer	Primer sequence	Primer site	EMBL accession no.	Reference
Gene
dfrA1 DH1	5′ CAAGTTTACATCTGACAATGAGAACGTAT 3′	429–459	X00926	8
dfrA1 DH2	5′ ACCCTTTTGCCAGATTTGGTA 3′	706–686	X00926	This study
dfrA1 DH9	5′ AGCTGTTCACCTTTGGC 3′	1059–1043	K00052	29
dfrB1 DH3	5′ GTTGGACTCAAATGATGACAATGTAGTTG 3′	430–460	S76821	36
dfrB1 DH4	5′ CCAAATTTGATAGCAATAGTT 3′	696–676	S76821	This study
dfrV DH5	5′ CCTGGACGGCCGATAATGACAACGTAATAG 3′	1501–1531	X12868	30
dfrV DH6	5′ CCAAATTTGATAGCAATAGTT 3′	1767–1747	X12868	This study
dfrVIII DH7	5′ AAGCGCTGGAGCTTCCGGGTGTTCGTGACG 3′	906–935	U09273	3
dfrVIII DH8	5′ ATTCTGTAAGCTCCTTTTTAC 3′	1211–1190	U09273	This study
Integron
5′-CS	5′ GGCATCCAAGCAGCAAG 3′	1190–1206	M73819	18
3′-CS	5′ AAGCAGACTTGACCTGA 3′	1342–1326	M73819	18
aadA1a	5′ TCGATGACGCCAACTAC 3′	464–448	X02340	15
Int1A	5′ AAAACCGCCACTGCGCCGTTA 3′	1300–1278	M95287	This study
Int1B	5′ GAAGACGGCTGCACTGAACG 3′	100–115	M95287	This study
Int2A	5′ ATGTCTAACAGTCCATTTTTAAATTCTA 3′	1474–1495	AJ002782	This study
Int2B	5′ AAATCTTTAACCCGCAAACGC 3′	1917–1887	AJ002782	This study
Int3A	5′ GTGGCGCAGGGTGTGGAC 3′	194–211	D50438	2
Int3B	5′ ACAGACCGAGAAGGCTTATG 3′	959–939	D50438	2
sul1	5′ CTTCGATGAGAGCCGGCGGC	924–943	X12869	30
sul1R	5′ GCAAGGCGGAAACCCGCGCC	1360–1341	X12869	30