The biochemical prerequisites for preventing pathogenic lysolecithin activity in the human gallbladder. II. Studies on the subcellular localization of lysophospholipase.

The subcellular localization of lysophospholipase activity in the human gallbladder epithelium was studied by differential and density gradient centrifugation. The highest relative specific activity was found in the microsomal fraction, although the enzyme appeared in mitochondria and lysosomes as well. The cytosol did not contain any significant lysophospholipase activity, but large amounts of enzyme were solubilized during centrifugation in sucrose gradients. These findings are discussed in relation to the distribution and properties of lysophospholipase in other cells and tissues and with regard to physiological implications. The possible relevance to the pathogenesis of aseptic cholecystitis is inferred.