title: Effect of membrane phospholipid composition and charge of the signal peptide of Escherichia coli alkaline phosphatase on efficiency of its secretion.
abstract: The secretion of the Escherichia coli alkaline phosphatase with a different charge of signal peptide due to replacement of positively charged Lys(-20) has been studied depending on the phospholipid composition of the membranes and the activity of the translocational ATPase--protein SecA. Changing the signal peptide charge, along with a change in phospholipid composition, has been shown to reduce the efficiency of secretion. In the absence of phosphatidylethanolamine the membrane contains anionic phospholipids only, and the dependence of secretion on the signal peptide charge decreases. The dependence of secretion on membrane phospholipid composition and the signal peptide charge is also determined by the activity of SecA protein. If SecA is inactivated by sodium azide, then the dependence of secretion on anionic phospholipids increases; on the contrary, higher content of anionic phospholipids (in the absence of phosphatidylethanolamine) decreases the dependence of secretion on the SecA activity. The results suggest a direct interaction of positively charged signal peptide with negatively charged membrane phospholipids under initiation of secretion and also interdependent contribution of the signal peptide charge, anionic phospholipids, and translocational ATPase to secretion.
authors: Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, 142290, Moscow Region, Russia.
authors: V V
authors: VV
authors: Golovastov
authors: M A
authors: MA
authors: Nesmeyanova
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism*; D004926:Escherichia coli / Q000737:chemistry / Q000166:cytology* / Q000201:enzymology* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D021382:Protein Sorting Signals; D021381:Protein Transport; D000069816:SEC Translocation Channels; D000081416:SecA Proteins; D055672:Static Electricity
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D010743:Phospholipids; D021382:Protein Sorting Signals; D000069816:SEC Translocation Channels; D000469:Alkaline Phosphatase; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins