ADP-binding subunit of the dihydroxyacetone kinase, which is responsible for the phosphoenolpyruvate (PEP)-dependent phosphorylation of dihydroxyacetone (PubMed:11350937). DhaL-ADP is converted to DhaL-ATP via a phosphoryl group transfer from DhaM and transmits it to dihydroxyacetone bound to DhaK (PubMed:11350937). DhaL acts also as coactivator of the transcription activator DhaR by binding to the sensor domain of DhaR (PubMed:15616579). In the presence of dihydroxyacetone, DhaL-ADP displaces DhaK and stimulates DhaR activity (PubMed:15616579). In the absence of dihydroxyacetone, DhaL-ADP is converted by the PTS to DhaL-ATP, which does not bind to DhaR (PubMed:15616579). dihydroxyacetone + phosphoenolpyruvate = dihydroxyacetone phosphate + pyruvate kcat is 2.8 sec(-1). Values measured with the DhaKLM complex. Complexation with ADP increases the thermal unfolding temperature from 40 to 65 degrees Celsius. Polyol metabolism; glycerol degradation. Homodimer (PubMed:16647083, PubMed:21209328, PubMed:24440518). The dihydroxyacetone kinase complex is composed of a homodimer of DhaM, a homodimer of DhaK and the subunit DhaL (PubMed:16647083, PubMed:21209328). DhaL also forms a complex with DhaR (PubMed:24440518). Activated by DhaR. Unlike the carbohydrate-specific transporters of the PTS, the complex DhaKML has no transport activity. The tightly bound ADP participates in a double displacement phosphoryl transfer reaction and thus plays the same role as histidines, cysteines and aspartic acids in other phosphoprotein intermediates.