The gonococcal isolates from 15 contact pairs and three large contact groups were examined using various methods to assess the stability of different typing markers. With the exception of one contact group which showed variable proline requirements, the auxotypes were stable during natural transmission. Serogrouping using the coagglutination method to detect W and M antigens was undertaken. The...

We describe the use of electrogenerated reactants for continuous on-line reaction detection with thin-layer hydrodynamic amperometry. The reagent is introduced into the liquid-chromatographic column effluent at a constant rate by using controlled-current electrochemistry. After the effluent passes through a short reaction coil, the reagent concentration is monitored at the detector. Reaction of...

The plasmid patterns of 90 isolates of Neisseria gonorrhoeae (including 39 penicillinase-producing strains) originating from various countries in Africa were determined. Serogrouping by coagglutination and auxotyping were used to characterise the isolates. The 4.4-megadalton plasmid was present in seven isolates out of 39 penicillinase-producing strains, two of which occurred with a conjugative...

Streptococcal grouping sera, diluted and absorbed to remove cross-reactions, were bound to staphylococci and used to group trypsinised beta-haemolytic streptococci by coagglutination. The results compared well with those obtained using the Phadebact streptococcal grouping kit. The same sera bound to staphylococci without prior dilution and absorption could be used to group enzyme extracts of ha...

The coagglutination test, which uses staphylococcal protein A, for serotyping strains of Streptococcus pneumoniae, was extended to include serotyping within serogroups. Serotyping was performed with "factor sera" prepared in the laboratory. Fifty one strains of S pneumoniae, which belonged to one of the seven serogroups included in the 14 valent vaccine formulation, were tested, and no inconsis...

Streptococcal grouping sera, diluted and absorbed to remove cross-reactions, were bound to staphylococci and used to group trypsinised beta-haemolytic streptococci by coagglutination. The results compared well with those obtained using the Phadebact streptococcal grouping kit. The same sera bound to staphylococci without prior dilution and absorption could be used to group enzyme extracts of ha...