Exhibits phospholipase B (PLB), lysophospholipase (LPL) and lysophospholipase/transacylase (LPTA) activities. a 1-acyl-sn-glycero-3-phosphocholine + H2O = a fatty acid + H(+) + sn-glycerol 3-phosphocholine Inhibited by Fe(3+) ion. Active only at acidic pHs. Localizes to lipid rafts in the cell membrane prior to secretion. N-glycosylated. Belongs to the lysophospholipase family. PubMed:10749672 describes peptide sequences that do not match PLB1, but originate from a copurified, contaminating chitin deacetylase.