[Phospholipid composition in thermosensitive mutants of Escherichia coli (author's transl)]

Quantitative phospholipid composition was investigated on various thermo-sensitive mutants of Escherichia coli K 12. Phosphatidylethanolamine was the major component. Three mutants (T1, T46 and T5) grown at 40 degrees C, had more anionic phospholipids (phosphatidylglycerol and diphosphatidylglycerol) and less bipolar phospholipids (phosphatidylethanolamine and lysophosphatidylethanolamine) than the wild type. Two mutants strains T46 and T83 which have the same Dna A mutation and identical membrane proteins alterations, have different phospholipid composition. Other mutants, such as T46, exhibit a blocking o? THE INITIATION OF DNA synthesis or morphological alterations under restrictive growth conditions (40 degrees C); however, the phospholipid composition of these mutants is normal and differs from the phospholipid composition of T46.T1 and T5 mutants have the same alterations in the phospholipid composition as T46 although they do not possess Dna A and Div A mutations of the T46 strain. Mutations leading to the alteration of the phospholipid composition are unrelated to other mutations leading to changes in the morphology and cellular division.