Newswise — Phospholipases are enzymes that cleave the tail group off of phospholipids, which make up cell membranes. These tails, or free fatty acids, can go on to act as signaling molecules. Lysosomal phospholipase A2, or LPA2, is a phospholipase from the macrophages that protect the lung. The enzyme is unusual in interacting with a wide range of substrates, and making two types of modification to phospholipids, acting as either an acyltransferase (which attaches the freed fatty acid tail to a new molecule) or phospholipase (which lets the free fatty acid go). Unlike many phospholipases, which are active at neutral pH, LPA2 is most active in the highly acidic environment typical of the lysosome.

To figure out why LPA2 has such strange enzymatic properties, researchers at the University of Michigan honed in on Asp13, a recently identified catalytic residue on the enzyme. A recent paper in the Journal of Lipid Research describes how substituting a variety of amino acids for Asp13 made LPA2 more active at neutral pH and less able to interact with the unsaturated acyl chains that it had previously favored. The study gives molecular insight into LPA2 activity.

DOI 10.1194/jlr.M084012




About the Journal of Lipid Research

The Journal of Lipid Research (JLR) is the most-cited journal devoted to lipids in the world. For over 50 years, it has focused on the science of lipids in health and disease. The JLR aims to be on the forefront of the emerging areas of genomics, proteomics, and lipidomics as they relate to lipid metabolism and function. For more information about JLR, visit

Journal Link: Journal of Lipid Research