FIG. 4.

Comparison of relative fluorescence (solid line) and average conservation (gray) of all probes targeted to E. coli. Conservation values for each probe were calculated by averaging the conservation values stated in the ARB database (27) for those positions targeted by a probe. The conservation values are based on the fractions of available bacterial sequences that have an identical nucleotide in a particular alignment position. They are expressed in arbitrary units (a.u.), where low values indicate low evolutionary conservation.