The paper presents studies of Langmuir monolayers of native phospholipids isolated from the cell membranes of the E. coli K-12 test culture. Six fatty acid methyl esters were found in the composition of E. coli K-12 bacteria lipid A: methyl hexadecanoate, methyl trans-9-octadecanoate, methyl cis-9-hexadecenoate, methyl cis-9,10-methylene hexadecanoate, methyl octadecanoate and methyl tetradecanoate. To form a monolayer, a working solution of native phospholipids in chloroform with a concentration of C=10-4 M was prepared. To study the effect of the aliquot volume of the working solution on the formation of the monolayer, phospholipids were introduced to the water surface in quantities V=50, 100 and 150 µl. Monolayers were studied by the method of compression isotherms, the analysis of which showed the presence of at least three stable densely packed states with high mechanical strength.
native phospholipids, Langmuir monolayers, stable states
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