Some physiological and toxigenic properties of members of the genus Micrococcus in relation to taxonomy

Abstract

The controversy over the validity of the existence of the two genera Micrococcus and Staphylococcus (1, 7, 8, 9, 17) has been reopened recently. Resolution of the question had been attempted in the last edition of the Bergey Manual (5) by relegation of the Staphylococcus to a position of synonymy and definition of a series of species of Micrococcus to comprehend those of the two former genera closely in accord with the work of Hucker (12). Apart from the question of the respective taxonomic legitimacy of retention of the two generic names (l), argument favouring recognition of the generic name Staphylococcus seems to centre upon a primary intent to reserve the generic name Staphylococcus for toxigenic forms of the non-chained Gram-positive micrococci. It has been suggested that t he proposed be based upon the type s pecies Staphylococcus - aureus Rosenbach (for which the specific name Pyogenes has also been preferred (8)) and for which culture F.D.A. 209 P (15) and, more recently, S33 R4 (7) have each been proposed as the type-culture in the absence of an adequate record of a typeculture for the as originally propounded by Rosenbach (9). A number of properties other than the rrkeyrr characteristics listed in the Bergey Manual have been described as being helpful aids in classification of this heterogeneous group, particularly with the objective of distinguishing between toxigenic (or pathogenic) and nontoxigenic forms. Gupta and Chakravarti (10) have recorded that pathogenic strains of the micrococci provide positive tests for both the methyl red and Voges Proskauer reactions while Evans, Bradford, and Niven (8) refer to coagulase-posit ive staphylococci'l as one of the most hamogeneous species of bacteria to be found in any genus and recommend that this species be recognized as the type species for the Staphylococcus, a species s aid to be differentiable f urther by its property of the production of acid from glucose anaerobically in a defined complex medium. 'A contribution from the Microbiology Section of the Laboratories of the Food and Drug Directorate, Department of National H ealth and Welfare, Ottawa, Canada.