Purification and properties of extracellular lipase from Pseudomonas aeruginosa EF2 Gilbert, E. Jane and Cornish, Alex and Jones, Colin W.,, 137, 2223-2229 (1991), doi = https://doi.org/10.1099/00221287-137-9-2223, publicationName = Microbiology Society, issn = 1350-0872, abstract= Summary: Extracellular lipase was purified from a Tween 80-limited continuous culture of Pseudomonas aeruginosa EF2 by ultrafiltration of the culture supernatant followed by anion-exchange and gel-filtration FPLC. The lipase was composed of a single subunit (M r29000, pI 4·9), which was capable of a variable degree of aggregation, and which exhibited both lipase activity, measured with the insoluble substrate olive oil (predominantly triolein), and esterase activity, measured with the soluble substrates p-nitrophenyl acetate and Tween 80. Lipase activity was approximately eight times higher than either type of esterase activity (k cat, approximately 3000 s−1for the hydrolysis of olive oil). The enzyme showed a marked regiospecificity for the 1,3-oleyl residues of radiolabelled triolein, was relatively stable at moderate temperatures (exhibiting a biphasic loss of activity with an initial t 1/2 of 17·5 min at 60 °C) and was very stable to freezing and thawing. Lipase activity was only weakly inhibited by the serine-active reagent 3,4-dichloroisocoumarin, and was not inhibited by the chelating agent EDTA (1 mm). The N-terminal amino acid sequence of the Ps. aeruginosa EF2 lipase showed a marked similarity to those of several other bacterial lipases., language=, type=