title: Heterologous overexpression of a monotopic glucosyltransferase (MGS) induces fatty acid remodeling in Escherichia coli membranes.
abstract: The membrane protein monoglucosyldiacylglycerol synthase (MGS) from Acholeplasma laidlawii is responsible for the creation of intracellular membranes when overexpressed in Escherichia coli (E. coli). The present study investigates time dependent changes in composition and properties of E. coli membranes during 22h of MGS induction. The lipid/protein ratio increased by 38% in MGS-expressing cells compared to control cells. Time-dependent screening of lipids during this period indicated differences in fatty acid modeling. (1) Unsaturation levels remained constant for MGS cells (~62%) but significantly decreased in control cells (from 61% to 36%). (2) Cyclopropanated fatty acid content was lower in MGS producing cells while control cells had an increased cyclopropanation activity. Among all lipids, phosphatidylethanolamine (PE) was detected to be the most affected species in terms of cyclopropanation. Higher levels of unsaturation, lowered cyclopropanation levels and decreased transcription of the gene for cyclopropane fatty acid synthase (CFA) all indicate the tendency of the MGS protein to force E. coli membranes to alter its usual fatty acid composition.
authors.affiliation: The Arrhenius Laboratories for Natural Sciences, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden. Electronic address: candan@dbb.su.se.
authors.forename: Candan
authors.initials: C
authors.lastname: Ariöz
authors.affiliation: The Arrhenius Laboratories for Natural Sciences, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Hansjörg
authors.initials: H
authors.lastname: Götzke
authors.affiliation: The Arrhenius Laboratories for Natural Sciences, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Ljubica
authors.initials: L
authors.lastname: Lindholm
authors.affiliation: BMC, Department of Chemistry, Uppsala University, SE-751 23 Uppsala, Sweden.
authors.forename: Jonny
authors.initials: J
authors.lastname: Eriksson
authors.affiliation: BMC, Department of Chemistry, Uppsala University, SE-751 23 Uppsala, Sweden.
authors.forename: Katarina
authors.initials: K
authors.lastname: Edwards
authors.affiliation: The Arrhenius Laboratories for Natural Sciences, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Daniel O
authors.initials: DO
authors.lastname: Daley
authors.affiliation: The Arrhenius Laboratories for Natural Sciences, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Barth
authors.affiliation: The Arrhenius Laboratories for Natural Sciences, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Ake
authors.initials: A
authors.lastname: Wieslander
mesh_terms: D000128:Acholeplasma laidlawii / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005964:Glucosyltransferases / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008780:Methyltransferases / Q000378:metabolism; D008958:Models, Molecular; D010714:Phosphatidylethanolamines / Q000378:metabolism; D017433:Protein Structure, Secondary
chemical_list: D005227:Fatty Acids; D008563:Membrane Lipids; D008565:Membrane Proteins; D010714:Phosphatidylethanolamines; C483858:phosphatidylethanolamine; D008780:Methyltransferases; C019964:cyclopropane synthetase; D005964:Glucosyltransferases
keywords: Cyclopropanation; Fatty acid modeling; Intracellular membrane; Lipid–protein interaction; Membrane fluidity; Monotopic membrane protein