Table 1.

Primers used in this study.

Primers	Sequences
iucA for	GTACATCCGTGGCAGTGGCAG
iucA rev	CAAGCGCGGCATAGCCTTCAT
ybtS for	CAAAAATGGGCGGTGGATTC
ybtS rev	CCTGACGGAACATAAACGAGCG
iroN for	GCATTGGTATTCCAGTTCAGACG
iroN rev	GAAAGGCAACGGTTGTCCAAA
EntB for	TGAAGACGATACCGTGCTGGTGGA
EntB rev	GTCGGCGACAAAGAACGGTTTGAT
K10	GGGCTGCAGTTCCGCCGCCCAGTAGATTTC
K11	GCGCAGTGCTTCCTTAATTCCTGGAACGTAAAAGGTAACTTT
K12	AAAGTTACCTTTTACGTTCCAGGAATTAAGGAAGCACTGCGC
K13	GGGGGATCCCCGCGGTGACGTGCCAGG

Key: Restriction enzymes are highlighted by boldface. For, forward. rev, reverse.