AN APPROACH TO THE STUDY OF INTERACTIVE PHENOMENA AMONG MICROORGANISMS INDIGENOUS TO MAN

Abstract

A simple, sensitive and roughly quantitative method is descr. for screening and preliminary classification of interactive phenomena among pairs of microorganisms cultivable on agar media. A cross-titration over a 1000-fold range of concn. of each sp. is performed on each plate with 16 pairs of overlapping drops of inoculum, using 4 successive 10-fold dilutions of each sp. Inoculum concns. are estimated from separate drop counts. The method has been applied in a preliminary survey of aerobic microorganisms characteristic of human mucous membranes as part of an ecological study in relation to human hygiene. The findings are compared with those of previous workers, and suggestions offered regarding their possible significance.