TY - JOUR

T1 - Extracellular lipase of Pseudomonas aeruginosa: biochemical characterization and effect on human neutrophil and monocyte function in vitro

AU - Jaeger, K E

AU - Kharazmi, A

AU - Høiby, N

N1 - Keywords: Cell Survival; Chemotaxis, Leukocyte; Chromatography, Gel; Electrophoresis, Polyacrylamide Gel; Humans; Lipase; Luminescent Measurements; Monocytes; Neutrophils; Pseudomonas aeruginosa; Sodium Dodecyl Sulfate

PY - 1991

Y1 - 1991

N2 - Lipase was isolated from P. aeruginosa by ultrafiltration of sterile-filtered culture supernatant. Gel filtration on Sepharose 4B yielded a broad peak corresponding to a molecular mass range of 100 to 1000 kDa. Electron microscopy of a negatively stained lipase preparation after Sepharose 4B chromatography revealed spherical particles with diameters ranging from 5 to 20 nm. Biochemical characterization and SDS polyacrylamide gel electrophoresis suggested that these particles consisted of protein and carbohydrate including lipopolysaccharide with the major enzyme activity being lipase. Various concentrations of this lipase preparation were preincubated with human peripheral blood neutrophils and monocytes. The chemotaxis and chemiluminescence of these cells were then determined. It was shown that lipase inhibited the monocyte chemotaxis and chemiluminescence, whereas it had no or very little effect on neutrophils. The inhibitory effect was concentration dependent and was abolished by heat treatment of the enzyme at 100 degrees C. Since monocytes are one of the important cells of the host defence system the inhibition of the function of these cells may contribute to the pathogenesis of infections caused by P. aeruginosa.

AB - Lipase was isolated from P. aeruginosa by ultrafiltration of sterile-filtered culture supernatant. Gel filtration on Sepharose 4B yielded a broad peak corresponding to a molecular mass range of 100 to 1000 kDa. Electron microscopy of a negatively stained lipase preparation after Sepharose 4B chromatography revealed spherical particles with diameters ranging from 5 to 20 nm. Biochemical characterization and SDS polyacrylamide gel electrophoresis suggested that these particles consisted of protein and carbohydrate including lipopolysaccharide with the major enzyme activity being lipase. Various concentrations of this lipase preparation were preincubated with human peripheral blood neutrophils and monocytes. The chemotaxis and chemiluminescence of these cells were then determined. It was shown that lipase inhibited the monocyte chemotaxis and chemiluminescence, whereas it had no or very little effect on neutrophils. The inhibitory effect was concentration dependent and was abolished by heat treatment of the enzyme at 100 degrees C. Since monocytes are one of the important cells of the host defence system the inhibition of the function of these cells may contribute to the pathogenesis of infections caused by P. aeruginosa.

M3 - Journal article

C2 - 1910141

VL - 10

SP - 173

EP - 182

JO - Microbial Pathogenesis

JF - Microbial Pathogenesis

SN - 0882-4010

IS - 3

ER -