title: Influence of phospholipid composition on excretion of beta-lactamase from a stringent/relaxed Escherichia coli K 12 strain pair.
abstract: In comparison to stringent (relA+) controlled Escherichia coli cells, relaxed (relA) controlled E. coli cells excreted more recombinant beta-lactamase into the culture medium. The analysis of the composition of phospholipid fractions of the cells yielded increased levels of phosphatidylserine in relaxed controlled cells. We added various phospholipid vesicles to growing cells in order to influence the excretion rate via their incorporation in the membranes. The addition of vesicles to phosphatidic acid, phosphatidylglycerol and phosphatidylserine reduced the excretion of beta-lactamase whereas vesicles of phosphatidylethanolamine and phosphatidylcholine decreased or increased the excretion of beta-lactamase in dependence on the individual fatty acid residues of the added phospholipids. The lower the degree of saturation of the added phospholipids the more permeable was the cell envelope for beta-lactamase.
authors.affiliation: Hans-Knöll-Institut für Naturstoff-Forschung e. V., Jena, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Gitter
authors.forename: D
authors.initials: D
authors.lastname: Riesenberg
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003470:Culture Media / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D005227:Fatty Acids / Q000378:metabolism; D014644:Genetic Variation; D010712:Phosphatidic Acids / Q000494:pharmacology; D010713:Phosphatidylcholines / Q000494:pharmacology; D010714:Phosphatidylethanolamines / Q000494:pharmacology; D010715:Phosphatidylglycerols / Q000494:pharmacology; D010718:Phosphatidylserines / Q000378:metabolism / Q000494:pharmacology; D011994:Recombinant Proteins / Q000378:metabolism*; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D003470:Culture Media; D005227:Fatty Acids; D010712:Phosphatidic Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010715:Phosphatidylglycerols; D010718:Phosphatidylserines; D011994:Recombinant Proteins; D001618:beta-Lactamases