protein-containing complex DNA recombinase mediator complex A protein complex containing accessory proteins which bind a recombinase (e.g. Rad51) and bind single-stranded DNA (ssDNA), and promote nucleation of the recombinase onto ssDNA through facilitating recombinase-RPA exchange. Many paralogs of Rad51 act as recombinase mediators. These paralogs dimerize (or occasionally form tetramers) amongst themselves to form complexes with ssDNA-binding activity, and which act as mediators of Rad51 presynaptic filament assembly. GO:0033061 cellular_component