title: An interfacial and comparative in vitro study of gastrointestinal lipases and Yarrowia lipolytica LIP2 lipase, a candidate for enzyme replacement therapy.
abstract: Lipolytic activities of Yarrowia lipolytica LIP2 lipase (YLLIP2), human pancreatic (HPL) and dog gastric (DGL) lipases were first compared using lecithin-stabilized triacylglycerol (TAG) emulsions (Intralipid) at various pH and bile salt concentrations. Like DGL, YLLIP2 was able to hydrolyze TAG droplets covered by a lecithin monolayer, while HPL was not directly active on that substrate. These results were in good agreement with the respective kinetics of adsorption on phosphatidylcholine (PC) monomolecular films of the same three lipases, YLLIP2 being the most tensioactive lipase. YLLIP2 adsorption onto a PC monolayer spread at the air/water interface was influenced by pH-dependent changes in the enzyme/lipid interfacial association constant (KAds) which was optimum at pH 6.0 on long-chain egg PC monolayer, and at pH 5.0 on medium chain dilauroylphosphatidylcholine film. Using substrate monolayers (1,2-dicaprin, trioctanoin), YLLIP2 displayed the highest lipolytic activities on both substrates in the 25-35 mN m(-1) surface pressure range. YLLIP2 was active in a large pH range and displayed a pH-dependent activity profile combining DGL and HPL features at pH values found in the stomach (pH 3-5) and in the intestine (pH 6-7), respectively. The apparent maximum activity of YLLIP2 was observed at acidic pH 4-6 and was therefore well correlated with an efficient interfacial binding at these pH levels, whatever the type of interfaces (Intralipid emulsions, substrate or PC monolayers). All these findings support the use of YLLIP2 in enzyme replacement therapy for the treatment of pancreatic exocrine insufficiency, a pathological situation in which an acidification of intestinal contents occurs.
authors.affiliation: CNRS, Aix-Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse, UMR 7282, 31 chemin Joseph Aiguier, 13402 Marseille cedex 20, France.
authors.forename: Anaïs
authors.initials: A
authors.lastname: Bénarouche
authors.affiliation: CNRS, Aix-Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse, UMR 7282, 31 chemin Joseph Aiguier, 13402 Marseille cedex 20, France.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Point
authors.affiliation: CNRS, Aix-Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse, UMR 7282, 31 chemin Joseph Aiguier, 13402 Marseille cedex 20, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Carrière
authors.affiliation: CNRS, Aix-Marseille Université, Enzymologie Interfaciale et Physiologie de la Lipolyse, UMR 7282, 31 chemin Joseph Aiguier, 13402 Marseille cedex 20, France. Electronic address: jfcavalier@imm.cnrs.fr.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Cavalier
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000633:toxicity; D004285:Dogs; D056947:Enzyme Replacement Therapy; D004795:Enzyme Stability / Q000235:genetics*; D010188:Exocrine Pancreatic Insufficiency / Q000201:enzymology / Q000473:pathology / Q000628:therapy*; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000201:enzymology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000737:chemistry* / Q000378:metabolism; D025062:Yarrowia / Q000201:enzymology*
chemical_list: D001647:Bile Acids and Salts; D005656:Fungal Proteins; C408971:LIP2 protein, Yarrowia lipolytica; D008049:Lipase
keywords: Enzyme adsorption; Enzyme kinetics; Interfacial enzymology; Lipase; Monomolecular film