title: Degradation of soluble laminin and depletion of tissue-associated basement membrane laminin by Pseudomonas aeruginosa elastase and alkaline protease.
abstract: Purified Pseudomonas aeruginosa elastase and alkaline protease rapidly cleaved soluble laminin, with each enzyme yielding different cleavage products. These cleavage fragments were separated from the intact laminin A and B polypeptide chains by sodium dodecyl sulfate-polyacrylamide gradient gel electrophoresis and detected by their characteristic Coomassie blue staining patterns. Pseudomonas elastase produced rapid and extensive degradation of both A and B chains, including the disulfide-rich regions. Apparently complete degradation to limit digests was obtained after 30 min with a substrate/enzyme ratio of 30:0.5. Under similar conditions, alkaline protease rapidly degraded the A chain while slowly degrading the B chain. In addition, immunoreactive laminin was released from authentic basement membranes after incubation with either enzyme as detected by an enzyme-linked immunoabsorption assay and by immunofluorescence. The results from these studies suggest a direct role for elastase and alkaline protease in both tissue invasion and hemorrhagic tissue necrosis in P. aeruginosa infections.
mesh_terms: D000818:Animals; D001485:Basement Membrane / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism*; D005109:Extracellular Matrix / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D066298:In Vitro Techniques; D007797:Laminin / Q000378:metabolism*; D051379:Mice; D010196:Pancreatic Elastase / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D012697:Serine Endopeptidases; D012995:Solubility
chemical_list: D007797:Laminin; D010450:Endopeptidases; D012697:Serine Endopeptidases; D010196:Pancreatic Elastase; C032923:microbial serine proteinases