FIG. 1.

Dendrogram of BIOLOG profiles of nonpathogenic fluorescent and nonfluorescent strains of E. coli and pathogenic O157:H7. BIOLOG GN plates were read 4 h after application of the bacteria. Results from the BIOLOG test were subjected to cluster analysis with the MLCLUST program based on the unweighted pair group method with arithmetic means. The scale is in units of taxonomic distance. To help distinguish patterns in the dendrogram, the strains are divided into groups designated by letters.