Identification of Rhodococcus, Gordona and Dietzia species using carbon source utilization tests ("Biotype-100" strips).

The "Biotype-100" identification system (BioMérieux, La Balme-Ies-Grottes, France) based on carbon source utilization was evaluated for its ability to discriminate among 10 species of Rhodococcus, 7 species of Gordona and one species of Dietzia. The type strains of three species of Tsukamurella and 8 species of Nocardia were also included in the study. Results were compared with chemotaxonomic and conventional data. Carbon source utilization was shown to be reliable, rapid and easy to use when compared with standard identification methods. The 29 species tested were unambiguously separated by carbon source utilization tests. Rhodococcus equi was found to be heterogenous.