[Interrelation between the available boundary lipids in the bacterial membrane and the respiratory chain function].
In order to establish a possible correlation between the expression of the boundary lipid and the NADH-oxidase activity, the temperature dependences of the membranes of bacteria grown at 14 and 38 degrees C were investigated. The Tmelt. for the boundary lipid determined by comparing the excimerization parameters of the fluorescent probe pyrene in the vicinity of the proteins and in the total lipid phase was directly correlated with Tgrowth. A similar temperature dependence was observed with the NADH-oxidase activity, i. e. inhibition of activity at T greater than Tmelt. coincided with the disappearance of the boundary lipid. Incorporation of a cis-unsaturated fatty acid (linoleic acid) into the membranes markedly decreased the structural heterogeneity of membrane lipids and caused a simultaneous inhibition of the NADH-oxidase activity. No structural-functional changes were observed in the case of saturated fatty acids (stearic acid). It was assumed that the presence of boundary lipids in the membrane is essential for the normal functioning of the multienzyme system of the respiratory chain. Presumably, the state of the immediate lipid environment controls the function of the micrococcal respiratory chain at the level of interaction between the carriers in the membrane.
D004579:Electron Transport; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D008041:Linoleic Acids / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism*; D008837:Micrococcus / Q000378:metabolism; D009097:Multienzyme Complexes / Q000378:metabolism*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D013229:Stearic Acids / Q000378:metabolism; D013696:Temperature
D005230:Fatty Acids, Nonesterified; D008041:Linoleic Acids; D008563:Membrane Lipids; D009097:Multienzyme Complexes; D013229:Stearic Acids; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases
Vzaimosviaz' mezhdu sushchestvovaniem pogranichnykh lipidov v bakterial'noĭ membrane i funktsionirovaniem dykhatel'noĭ tsepi.