[Lipoamino acids in the composition of actinomycete polar lipids]

The capacity for substitution of phospholipids, in particular phosphatidyl ethanolamine, by a phosphorus-lacking lipoamino acid was studied in different groups of actinomycetes. In the conditions of phosphorus deficiency, most cultures were found to be capable of synthesizing a phosphorus-lacking nitrogen-containing lipoamino acid. Its characteristics (Rf) in TLC are similar to those of ornithinolipid. This fact confirms, for the first time and for different groups of actinomycetes, the hypothesis concerning interchangeability of membranous lipids. In the case of Actinomyces olivaceus, phosphatidyl ethanolamine and ornithine containing a phosphorus-lacking lipid can be regarded, this being corroborated by comparative data about their quantitative content. The detection of the phosphorus-lacking nitrogen-containing lipid in the composition of the polar fraction in different actinomycetes in the conditions of phosphorus deficiency in the medium demonstrates the possibility of adaptive changes in the composition of membranous lipids in microorganisms depending on their habitat.