STAPHYLOCOCCAL LIPASES - MOLECULAR CHARACTERIZATION, SECRETION, AND PROCESSING

Up to date five different staphylococcal lipase genes, two of Staphylo coccus aureus (sal-l and sal-2), two of Staphylococcus epidermidis (se l-1 and sel-2) and one of Staphylococcus hyicus (shl) have been cloned and sequenced. All corresponding proteins are organised as pre-pro-en zymes: the pre-region represents the signal peptide, the pro-region ha s a length between 207 and 267 amino acids, and the mature part compri ses 380 to 400 amino acids. We found that the lipases are secreted in the pro-lipase form. The processing of the pro-form to the mature enzy me occurs extracellular by a specific protease. Interestingly the pro- lipase reveals not much less activity compared to the mature lipase. T here are evidences that the pro-region acts as an intramolecular chape rone which facilitates translocation not only of the native lipase but also of a number of completely unrelated proteins fused to the pro-pe ptide. It was also observed that the pro-region protects the proteins from proteolytic degradation. While the Staphylococcus aureus and Stap hylococcus epidermidis lipases have only lipase (esterase) activity, t he related Staphylococcus hyicus enzyme (SHL) is distinguished by both lipase and phospho-lipase activity. The biochemical and catalytic pro perties of these lipases are described in the accompanying article (Si mons, J.W., Gotz, F., Egmont, M.R. and Verheij, H.M., 1998. Staphyloco ccal lipases: Biochemical properties. Accompanying article). (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.