ABSTRACT
High level tetracycline resistance of Neisseria gonorrhoeae is mediated by a 25.2-MD plasmid and is characterized by a minimal inhibitory concentration of 16 micrograms/ml or more. The 25.2-MD plasmid originated through the insertion of the streptococcal tetM determinant into the 24.5-MD transfer plasmid of N. gonorrhoeae. In the present study the prevalence of N. gonorrhoeae with high-level tetracycline resistance in the Heidelberg gonococcal population between 1981 and 1989 was determined. Among 1765 N. gonorrhoeae isolates, one strain with high-level tetracycline resistance was identified. The presence of the 25.2-MD plasmid in this strain was demonstrated by plasmid-agarose gel electrophoresis. The auxotype/serovar class proline-/IB-1 indicates the importation of this strain from the USA. The 25.2-MD recombinant plasmid, in contrast to the 24.5 MD transfer plasmid, has a rather wide host range, which is favourable to the occurrence both of high-level tetracycline resistance and of beta-lactamase plasmids in N. meningitidis.
Subject(s)
Bacterial Proteins/analysis , Neisseria gonorrhoeae/drug effects , Plasmids/immunology , Repressor Proteins/analysis , Tetracycline Resistance/genetics , Electrophoresis, Agar Gel , Plasmids/genetics , R FactorsABSTRACT
292 strains of non-fermenting Gram-negative rod-shaped bacteria were determined by standard methods and tested in a new commercial microidentification-system, the API 20 NE (api Biomérieux). A total of 282 (= 96,6%) strains were identified conformably; 130 (= 46,1%) after 24 h and 77 (= 27,3%) within 48 h. In 75 (= 26,6%) cases different conventional additional tests for determination to species level were necessary. The reasons for divergent results of 10 strains are discussed. The new microidentification system API 20 NE might be a simple and reliable tool in hand of the skilled medical microbiologist.
Subject(s)
Bacteriological Techniques , Gram-Negative Bacteria/classification , Alcaligenes/classification , Carbohydrate Metabolism , Flavobacterium/classification , Moraxella/classification , Pseudomonas/classificationABSTRACT
During a period of 16 months 1757 strains of nonfermentative gram-negative rods have been isolated from clinical material. Of the, 1205 (69%) were P. aeruginosa, 124 (10%) of which failed to produce pyocyanin. The apyocyaninogenic strains as well as the remaining 552 isolates were differentiated by steps according to a diagnostic scheme developed by us. For identification of species two or three steps were needed. By this procedure, 530 of the 552 strains could be assigned to nineteen species within the genera Pseudomonas, Achromobacter, Alcaligenes, Flavobacterium, Agrobacterium and Acinetobacter. 17 strains could not be identified below the genus level, one strain belonged to CDC-group VE-2 and four strains were not identifiable. 72% of the 552 strains belonged to only four species: Pseudomonas putida, P. maltophilia, Acinetobacter lwoffii and A. anitratus.
