Hydrolyzes glycerol-phospholipids at the terminal phosphodiesteric bond. Plays an important role in various cellular processes, including phytohormone action, vesicular trafficking, secretion, cytoskeletal arrangement, meiosis, tumor promotion, pathogenesis, membrane deterioration and senescence. a 1,2-diacyl-sn-glycero-3-phosphocholine + H2O = a 1,2-diacyl-sn-glycero-3-phosphate + choline + H(+) Ca(2+) requirement for activity depends on pH. Active either under acidic conditions with micromolar levels of calcium (PIP2-dependent) or at neutral pH with millimolar levels of calcium (PIP2-independent). C2 domain is a calcium-binding fold, and the binding promotes the protein association with membranes. A lower affinity toward calcium can be anticipated for PLD alpha C2 due to the absence of two potential calcium ligands. All eight cysteine residues were shown to have free sulfhydryl groups by mass spectrometry. The propeptide appears to play a key role in the proper folding and activation of the enzyme. Belongs to the phospholipase D family. C2-PLD subfamily.