Rapid method for identification of gram-negative, nonfermentative bacilli

Abstract

A rapid system (OA), based on oxidative attack of substrates, was developed for identification of gram-negative, nonfermentative bacillia (NFB). One hundred and twelve strains of NFB from 25 species (representing the genera Pseudomonas, Alcaligenes, Acinetobacter, Bordetella, Flavobacterium, Moraxella, and Xanthomonas) were assayed by OA, buffered single substrate, and oxidative/fermentative methods. The 38 substrates consisted of salts of organic acids, nitrogen-containing compounds, alcohols, and carbohydrates. Ninety-four percent of the test strains were identified by the OA method in 24 h, and 99% were identifiable in 48 h. Reproducibility was 99%. Correlation with buffered single substrate was 98% (all substrates) and 90% with the oxidative/fermentative method (carbohydrates only). Biochemical profiles of all strains are presented, as well as tables showing the most useful tests for identification.