AUTOMATION AND MINIATURIZATION OF PHYSIOLOGICAL TESTS - SOME APPLICATIONS IN NUMERICAL TAXONOMY AND NUMERICAL IDENTIFICATION

At present two trends are visible in microbial taxonomy. First, techno logical advances, especially the refinement of moleculargenetic techni ques, have opened new dimensions in microbial classification. Secondly , automation and miniaturization are integrated in almost all fields o f microbiology. The identification of various groups of microorganism, for example, seems to be possible by wing commercially available test systems. However the uncritical application of automated methods with out an appropriate scientific background may lead to wrong conclusions . In the study the application of miniaturized and automated tests in numerical taxonomy and numerical identification at the species level i s discussed for two bacterial genera, the genus Acinetobacter and the genus Streptomyces, on the basis of two previously published studies. The results of the numercial classification and identification show, t hat miniaturized biochemical tests (which can be read automatically) a re very useful for the differentiation of Acinetobacter genomospecies. In contrast to the genus Acinetobacter, classification of the genomic ally complex genus Streptomyces is based on extensive numerical taxono mic studies. To evaluate the value of miniaturized biochemical tests, 821 strains of the genus Streptomyces were physiologically characteriz ed wing 329 biochemical tests and the numerical techniques described a bove. It could be shown that the phenetic data in most cases confirm t he major phena obtained previously. A revised probability matrix of po sitive results for the phena was constructed Although the results indi cate, that the identification of Streptomyces species or species group s is possible, it should not be overlooked that the taxonomy of the ge nus is still unsatisfactory. A polyphasic approach including data obta ined from different method; is required to provide a sound basis of st reptomycete taxonomy.