Abstract: Objective To investigate the relationship between auxotypes,antibiotic resistance and plasmid of Neisseria gonorrhoeae.Methods 83 isolates of Neisseria gonorrhoeae from Chongqing during the period from January 1994 to November 1995 were examined.Results Eight auxotypes were detected in 83 strains.The prevalent auxotypes were proline requiring strains (51.8%) and nonrequiring (18.1%).The agar dilution method was performed to detect the susceptibility of 83 isolates to pencillin,tetracycline and spectinomycin,the results indicated that 15.6% of strains was penicillin resistant,70% was tetracycline resistant,1.2% was spectinomycin resistant.Plasmid profile of 44 isolates,which was tested by rapid alkaline extraction method,showed that 70% of the strains carried 24.5 Md conjugative plasmid,80% carried 2.6Md cryptic plasmid,66% carried both 24.5Md and 2.6Md plasmids,and no plasmid was found in 16% of the strains.In Pro^- strains both penicillin resistant strains and 24.5Md plasmid carrying strains were more common than other auxotypes (P<0.05).Tetracycline resistant strains were more common in than other strains (P<0.05) in strains containing 24.5Md and 2.6Md plasmids.One (PPNG) strain was detected and its 4.4Md plasmid encoding β lactamase was determined by plasmid elimination test.Conclusion This study shows not only the distribution of auxotypes,antibiotic resistance and plasmid profile,but also suggests certain relationship between them.It may be helpful in the epidemiological survey as well as control of gonorrhea in that area.

Key words: Neisseria genorrhoeae, Auxotype, Microbial sensitivity tests, Plasmid