Anionic Lipids Modulate the Activity of the Aquaglyceroporin GlpF.
The structure and composition of a biological membrane can severely influence the activity of membrane-embedded proteins. Here, we show that the E. coli aquaglyceroporin GlpF has only little activity in lipid bilayers formed from native E. coli lipids. Thus, at first glance, GlpF appears to not be optimized for its natural membrane environment. In fact, we found that GlpF activity was severely affected by negatively charged lipids regardless of the exact chemical nature of the lipid headgroup, whereas GlpF was not sensitive to changes in the lateral membrane pressure. These observations illustrate a potential mechanism by which the activity of an α-helical membrane protein is modulated by the negative charge density around the protein.
Institut für Pharmazie und Biochemie, Johannes Gutenberg Universität Mainz, Mainz, Germany.
Noreen
N
Klein
Institut für Molekulare Biophysik, Johannes Gutenberg Universität Mainz, Mainz, Germany.
Nadja
N
Hellmann
Institut für Pharmazie und Biochemie, Johannes Gutenberg Universität Mainz, Mainz, Germany. Electronic address: dirk.schneider@uni-mainz.de.
Dirk
D
Schneider
D000838:Anions / Q000737:chemistry; D020346:Aquaporins / Q000737:chemistry*; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry
D000838:Anions; D020346:Aquaporins; D029968:Escherichia coli Proteins; D008055:Lipids; D008081:Liposomes; C078043:GlpF protein, E coli