Cleaves phosphorylated sphingoid bases (PSBs), such as sphingosine-1-phosphate, into fatty aldehydes and phosphoethanolamine (By similarity). Sphingosine-1-phosphate (S1P) probably acts intracellularly as a second messenger perhaps by promoting cell proliferation; the absence of S1P lyase increases its concentration. This leads to increased lateral pseudopod formation as well as defects in the efficiency of chemotaxis (PubMed:15476260). Overexpression of S1P lyase causes decreased growth rates, entry into stationary phase at lower cell density and increased sensitivity to the antitumor agents cisplatin and carboplatin; these effects are more pronounced in cells that express more enzyme (PubMed:15190000). sphinganine 1-phosphate = hexadecanal + phosphoethanolamine Lipid metabolism; sphingolipid metabolism. Constitutively expressed during growth and development; not up-regulated by exposure to cisplatin. Cells produce short fruiting bodies with a thick stalk and drastically reduced numbers of spores. Mutant cells grow exponentially at the same rate as wild-type and are 25-fold more resistant to the antitumor agent cisplatin than are wild-type (PubMed:11566853). Mutant cells survive longer in stationary phase than wild-type cells, but are effected at multiple stages of development. Addition of 50 uM extracellular sphingosine-1-phosphate to wild-type cells mimics the developmental effect of the knockout (PubMed:11566853), and leads to increased cisplatin resistance (PubMed:15190000). Belongs to the group II decarboxylase family. Sphingosine-1-phosphate lyase subfamily.