Catalyzes the retro-aldol cleavage of 2-dehydro-3,6-dideoxy-6-sulfo-D-gluconate to (2S)-3-sulfolactaldehyde and pyruvate. Is involved in a degradation pathway of sulfoquinovose (SQ) that allows P.putida SQ1 to use SQ as the sole carbon and energy source for growth. 2-dehydro-3,6-dideoxy-6-sulfo-D-gluconate = (2S)-3-sulfolactaldehyde + pyruvate Binds 1 divalent metal cation per subunit. Homohexamer; trimer of dimers. Is highly up-regulated during growth on sulfoquinovose, compared to growth on glucose or succinate (at protein level). Belongs to the HpcH/HpaI aldolase family.