Genetic Mapping of Linked Antibiotic Resistance Loci in Neisseria gonorrhoeae

Abstract
Loci for resistance to several antibiotics in laboratory-derived strains of Neisseria gonorrhoeae were mapped by genetic transformation. Genes for high-level resistance to streptomycin ( str ) and spectinomycin ( spc ) and for low-level resistance to tetracycline ( tet ) and chloramphenicol ( chl ) were linked. Also, a locus for high-level resistance to rifampin ( rif ) was linked to str and tet . The apparent order was rif... str... tet... chl... spc . Loci for resistance to other antibiotics (penicillin, erythromycin) were transferred independently of each other and were not linked to the cluster around str . Similar linkage relationships were found with str, tet, chl , and spc loci obtained from naturally occurring (clinical) isolates of N. gonorrhoeae .