Cleaves 6-deoxy-6-sulfo-D-fructose 1-phosphate (SFP) to form dihydroxyacetone phosphate (DHAP) and 3-sulfolactaldehyde (SLA). 6-deoxy-6-sulfo-D-fructose 1-phosphate = (2S)-3-sulfolactaldehyde + dihydroxyacetone phosphate Induced during growth with sulfoquinovose. Mutant fails to grow on sulfoquinovose as a sole carbon source. Belongs to the aldolase LacD family.