The two component receiver domain of DctD from Sinorhizobium meliloti was used to search the non-redundant database at NCBI using the PSI-BLAST tool. The program failed to proceed beyond iteration three, and failed to converge, but identified 1148 matches. The results were used to download the amino acid sequences of 1148 response regulators from Entrez, which were then screened for the presence of predicted coiled-coils using a local installation of the PairCoil program. Adobe photoshop was then used to place a cartoon of the receiver domains relative to the regions bearing postitive signals for coiled coils to identify those regulators that might form a dimerization motif similar to that we have recently found for DctD (Meyer et al., FASEB J, accepted 12/2000). Fifty four response regulators, 4.6% of the total, were found to meet these criteria.