AP-PCR fingerprint profiles generated from S. sanguinis, other oral mitis group species, and S. sanguinis clinical isolates. AP-PCR results were obtained by amplification of genomic DNA with primer OPA-02. A 1.6-kb amplicon was observed for all S. sanguinis strains. Other reference strains of the mitis group showed different AP-PCR patterns and the absence of a 1.6-kb amplicon. The non-S. sanguinis strains tested were as follows: 10557, S. oralis; 10558, S. gordonii; 15911, S. parasanguinis; 9811, S. oralis; 903, S. mitis; 49999, S. cristatus; WU2, S. pneumoniae; 35037, S. oralis.