RDP provides quality-controlled, aligned and annotated Bacterial and Archaeal 16S rRNA sequences and Fungal 28S rRNA sequences and a suite of analysis tools to the scientific community.
SILVA provides comprehensive, quality checked and regularly updated datasets of aligned small (16S/18S, SSU) and large subunit (23S/28S, LSU) ribosomal RNA (rRNA) sequences for all three domains of life (Bacteria, Archaea and Eukarya).