Surfactin, a lipopeptide surfactant and antibiotic produced by Bacillus subtilis, exhibits a strong membrane perturbation. One of the drawbacks hindering its commercial applications is the unknown mechanism of surfactin self-resistance in the producer. Therefore, the aim of this study was to examine the self-protective mechanisms of the cytoplasmic membrane of B. subtilis against the deleterious effect of surfactin. In order to reach this task, two isogenic pairs of strains differing only in surfactin production were constructed. It was found out that the early response of the producer is realized by increasing the amount of total lipid content in the membrane already with the onset of surfactin synthesis. This process leads to lowering the surfactin-lipid ratio in the membrane. In parallel with the growing surfactin concentration the content of anionic phospholipids with cardiolipin as the major representative rises up to 24 % of the total. Together with the fall of phosphatidylethanolamine these changes promote the membrane stabilization and protect it against the interaction with surfactin. These alterations result in higher rigidity both of the polar head and hydrophobic chain region of the membrane as the steady state anisotropy of DPH and TMA-DPH showed. After 24 h of cultivation induction of...
Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:299118 |
Date | January 2011 |
Creators | Seydlová, Gabriela |
Contributors | Svobodová, Jaroslava, Spížek, Jaroslav, Julák, Alois |
Source Sets | Czech ETDs |
Language | Czech |
Detected Language | English |
Type | info:eu-repo/semantics/doctoralThesis |
Rights | info:eu-repo/semantics/restrictedAccess |
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