Plasmids of Neisseria gonorrhoeae and other Neisseria species

All plasmids in bacteria are units which replicate independently of the bacterial chromosome, are generally less than 1/20 the size of the bacterial chromosome, and contain the information for self-replication.The 2.6-megadalton (MDa) cryptic gonococcal plasmids were first identified in the genus Neisseria in 1972 (13).Since cryptic plasmids had no mea- surable phenotype, they attracted little attention.The impor- tance of plasmids in Neisseria spp.changed with the identi- fication of 1-lactamase plasmids in N. gonorrhoeae in 1976 ( 12).These plasmids encoded a P-lactamase which rendered the strains resistant to penicillin, the drug of choice for the therapy of gonorrhea at that time.