TABLE 1.

Hybrids of aadA1 and aadA2 gene cassettes

GenBank accession no.NameaOriginal nameOrderCrossover positionbChange(s) from standard cassettecCassette arraySpeciesReference or source
aadA2daadA1d
AF047479 aadA3 aadA3 2/1758-760C759T aadA3-aacA1/orfG-orfsH to M-catB3
AF326210 e aadA8 aadA8 2/1550-600C759T + 4fUnknown Klebsiella pneumoniae 12
AY139603 aadA8b aadA8 2/1602-647A402GgC759T aadA8b Uncultured 15
AY852272 aadA8b 2/1602-647T17A C216T dfrA12-orfF-aadA8bMixed cultureThis work
AY232671 aadA1 aadA1 2/188-101T17AC759T aadA2/1-blaP1 Pasteurella multocida 16
AY171244 e aadA21 aadA21 2/1148-159GC634-635CGg aadA21 Salmonella enterica serovar Typhimurium 2
AY550883 aadA21 aadA22 2/1148-159G790Ag aadA21 Salmonella enterica serovar Choleraesuis
AJ809407 aadA21 aadA23 2/1148-159G444Ag aadA21 Salmonella enterica serovar Agona
AB189176 aadA21 aadA23b 2/1148-159A529Gg aadA21 Escherichia coli
G790Ag
AY665771 h aadA12 aadA12 2/1/2148-159Unknown Escherichia coli
550-600
AB107663 aadA1 aadA1 1/2783-786G732C C759T aadA1/2 Vibrio cholerae
  • a Cassettes with high identity (>98%) to aadA1 or aadA21 are named aadA1 or aadA21, respectively.

  • b For boundary x-y, the last base identifiable as matching only the “front” cassette is x − 1, and the first base identifiable as matching only the “back” cassette is y + 1.

  • c Unless otherwise indicated, these differences are found in a number of other variants of the relevant cassette.

  • d The standard cassettes used for comparison are found in GenBank accession no. X12870 for aadA1, variants of which commonly have C759T , and X68227 for aadA2.

  • e The first 9 nucleotides of the cassette sequence are missing from AF326210, and the last 28 bp of the cassette sequence are missing from AY171244.

  • f The four additional changes are C609A, A612G, G773A (also found in the aadA1 cassette variant in AY139597), and the unique change C599T.

  • g The changes indicated have not been seen in any other variant of the relevant cassette.

  • h The sequence of the aadA12 gene only is present in AY665771.