Effect of Laurie Acid on Cell Division, Macromolecular Synthesis and Membrane Lipid Organization inEscherichia coli

摘要

Laurie acid (1 mg/ml) sharply suppressed the cell division of anacrAmutant strain ofEscherichia coliK12. However, the wild typeacrA$strain was resistant to the fatty acid. Capric acid and myristic acid were not so toxic. Laurie acid inhibited both DNA and protein synthesis of theacrAmutant strain, with the former being more sensitive than the latter. On the other hand, DNA polymerase activity of toluene-treated cells was stimulated rather than inhibited by the presence of 1 mg/ml of lauric acid. Fatty acid composition of phospholipids in the inner membrane was largely altered by the addition of lauric acid. These results suggest that addition of lauric acid to the medium causes a disorganization of the membrane lipids in theacrAmutant cell and activities of DNA polymerase and other intramembranous enzymes are consequently inhibited.