Schematic presentation of the Selective Capture of Transcribed Sequences (SCOTS) technique followed by Southern blot analysis of SCOTS identified sequences. In panel A, normalized bacterial cDNAs were obtained directly from bacteria grown in vitro in the Brain Heart Infusion broth or in vivo in the infected insect Rhizotrogus majalis. In panel B, cDNAs corresponding to genes preferentially expressed in R. majalis relative to the broth were enriched by differential cDNA hybridization. The enriched cDNAs were transformed into a cloning vector to build the cDNA library. Cloned inserts were amplified by PCR, equally transferred to two nylon membranes, and probed with digoxigenin labeled normalized in vivo cDNAs (left) or normalized in vitro cDNAs (right) as described in Methods. The dots at the same position in the two arrays were loaded with the same amplicon of each individual clone from the enriched cDNA library, and the concentration of probes was standardized to be same.