Abstract
Strains of Proteus mirabilis and P. vulgaris isolated in England, Scotland and Sweden were characterised by proticine production-proticine sensitivity (P-S) typing, O serotyping and Dienes typing methods. The determinants of O antigenicity were independent of those determining proticine production and proticine sensitivity. Because of this independence, the combination of P-S typing and O serotyping for the analysis of the 133 serotypable strains separated them into 81 distinct types whereas P-S typing and O serotyping methods alone separated them into only 56 and 19 types respectively. There was a relationship between the Dienes type and the P-S type; the determinants of Dienes compatibility were the proticine production-proticine sensitivity characters. The determinants of O antigenicity appeared to play no role in the Dienes reaction. Some strains that were indistinguishable by P-S typing and O serotyping methods were distinguished by Dienes typing.