Sequence analysis of the family of penicillinase-producing plasmids of Neisseria gonorrhoeae

The exact nature of the sequence differences between the medically importan t family of gonococcal penicillinase-producing plasmids has been ascertaine d. The entire DNA sequence of the Asia-type plasmid pJD4. demonstrated that it is 7426 bp and contains two direct repeats (DR30) that art: implicated in the formation of deletion variant plasmids. such as the Africa-type plas mid. We have identified putative DnaA and IHF binding sites, various open r eading frames that are thought to specify functional proteins, and some imp ortant DNA sequences involved with conjugative transfer of gonococcal p-lac tamase plasmids. The deletion in the Africa-type plasmid is 1827 bp and one of the DR30 repeats is also missing. The deletion in the Rio-type plasmid and several Toronto-type plasmids was determined to br 2273 bp and the sequ ence spanning the deletion was identical irrespective of geographic or temp oral origin. The Nimes-type plasmid is an African-type plasmid and also con tains an IS5 insertion sequence. Since IS5 has not been identified in gonoc occal isolates, we suggest that this sequence may have been inserted after the original gonococcal plasmid was transformed into Escherichia coli. The New Zealand plasmid is an Asia-type plasmid that contains an endogenous tan dem duplication of 1883 bp and the direct DR2 is implicated in this duplica tion. The nature of the defined truncation of Tn2 present in the various pl asmids is also discussed. (C) 2000 Academic Press.