Mechanism of calcium ion induced multilamellar vesicle DNA interaction

The effect of Ca2+ on the DNA interaction with anionic and neutral multilamellar vesicles (MLV) has been investigated. DNA from wheat (Triticum aestivum L. Gerek) was introduced to a suspension of MLV, composed of phosphatidylcholine (PC): dicetylphosphate (DCP):cholesterol (CHOL) at different molar ratios, to which Ca2+ (5-75 mM) was subsequently added. Indication of aggregation and/or fusion was obtained via light-scattering examination following the addition of Ca2+ and DNA to the MLV medium. Using a UV spectrophotometric assay, it was observed that although DNA alone has no effect on negatively charged MLV, it enhances liposomal interaction in the presence of calcium ions. The minimal Ca2+ concentration required to promote the interaction was detected to be 10 mM, and the highest level of interaction was observed at 75 mM. The aggregation/fusion of vesicles was detected for uncharged MLV (with no DCP in their structure), as well as for the anionic ones containing c. 10% CHOL, but not for anionic MLV containing 40% CHOL. This is explained in terms of cholesterol decreasing the membrane fluidity (above the Tc of components) as a result of which more rigid vesicles become less prone to aggregation/fusion interactions.


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Immunological mechanisms making contribution to discriminating signals obtained from commensal versus pathogenic bacteria is an active area of research and recent evidence proposes that commensals and pathogens might express discrete variants of pathogen associated molecular patterns (PAMP). We hypothesized that as a major member of PAMP, bacterial DNA (bacDNA) originating from commensals versus pathogens might possess distinct immunostimulatory activities, enabling their dis- crimination by the immune syst...
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MBTD1, a H4K20me reader, has recently been identified as a component of the NuA4/TIP60 acetyltransferase complex, regulating gene expression and DNA repair. NuA4/TIP60 inhibits 53BP1 binding to chromatin through recognition of the H4K20me mark by MBTD1 and acetylation of H2AK15, blocking the ubiquitination mark required for 53BP1 localization at DNA breaks. The NuA4/TIP60 non-catalytic subunit EPC1 enlists MBTD1 into the complex, but the detailed molecular mechanism remains incompletely explored. Here, we p...
Highly sensitive and selective colorimetric probe for determination of L-cysteine in aqueous media based on Ag/Pd bimetallic nanoparticles
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The interaction between Ag/Pd bimetallic nanoparticles and cysteine was introduced as a new and high potential colorimetric probe for the selective, sensitive and low-cost recognition and monitoring of cysteine in aqueous samples. In the presence of NaCl, cysteine was able to induce the aggregation of Ag/Pd bimetallic nanoparticles thereby resulting in a change in yellowish-brown color of the Ag/Pd colloid to green. The presence of 6.6 mM NaCl in the samples decreases the electrostatic repulsion and acceler...
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Unmethylated CpG motifs present in bacterial DNA rapidly trigger an innate immune response characterized by the activation of Ig- and cytokine-secreting cells. Synthetic oligonucleotides (ODNs) containing CpG motifs mimic this activity, triggering monocytes to proliferate, secrete and/or differentiate. Analysis of hundreds of novel ODNs led to the identification of two structurally distinct classes of CpG motif that differentially activate human monocytes. ODNs of the "K"-type interact with Toll-like recept...
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Triplex nucleic acid structures receive considerable attention due to their possible role in anti-gene therapy, several diseases as Friedreich's ataxia and Deoxyribonucleic acid (DNA) based nano-structures. The modulation of triplex formation and its stabilization using small molecules is one way to enhance their utility in such applications. Here, we synthesized five new Azacyanines (Azaethyl (2 b), Azapropyl (2 c), Azaisopropyl (2 d), Azabutyl (2 e), Azaisobutyl (2 f)) and assessed their affinity and sele...
Citation Formats
M. Mozafari and V. N. Hasırcı, “Mechanism of calcium ion induced multilamellar vesicle DNA interaction,” JOURNAL OF MICROENCAPSULATION, pp. 55–65, 1998, Accessed: 00, 2020. [Online]. Available: