On the origin of matrix mechanism in protocells and key problems of molecular biology.

The theory of the emergence of the matrix mechanism in protocells on complexes of minerals (apatite, carbonate-apatite, calcite, and quartz) with the reciprocal proportions and with the participation of the gas phase radicals (NH3, CH4, and CO) is considered. The structure of apatite and carbonate-apatite predetermined the formation of a double helix of DNA with the complementary pairs of purine-pyrimidine bases, as well as RNA strands complementary to DNA, and helical protein chains combined into supramolecular structures with RNA. It is proposed that during the Archean Eon, a gradual replacement of the mineral matrix with organic matter took place. The site of the origin of the matrix mechanism is the defect-free and growing defective zone of apatite and carbonate-apatite. The size and specificity of DNA, complementary-bound RNA and protein molecules in supramolecular protein-RNA complexes increased as defects accumulated in the structure of minerals. An increase in the size of RNA transcripts was accompanied by an increase in the number of protein molecules in supramolecular protein-RNA complexes. At the first, anhydrous, stage, the formation of a transcriptional-translational apparatus in the form of a crystalline organic-mineral complex -DNA, RNA and protein, based on the "spiral into spiral" principle of gas phase elements. The appearance of water determined the launch of the transcriptional-translational apparatus and the transformation of the organo-mineral crystalline complex into a liquid-crystalline state. A detailed description of the preparation and launch of the matrix mechanism is given. The following problems are discussed: the origin of ribosomal proteins and the role of super-specific aminoacyl-tRNA synthetase as a true carrier of genetic information; properties of the genetic code and synthesis of protocells without violating the second law of thermodynamics; the origin of biological asymmetry; the appearance of nanobacteria and dark genetic matter of eukaryotic systems.Communicated by Ramaswamy H. Sarma.

The influence of monogalactosyldiacylglycerols from different marine macrophytes on immunogenicity and conformation of protein antigen of tubular immunostimulating complex.

The tubular immunostimulating complex (TI-complex) is a novel nanoparticulate antigen delivery system consisting of cholesterol, triterpene glycoside cucumarioside A(2)-2, and glycolipid monogalactosyldiacylglycerol (MGDG) isolated from marine macrophytes. MGDG is crucial for the formation of a lipid matrix for the protein antigen incorporated in TI-complexes. Fatty acid composition and the physical state of this glycolipid depend on the taxonomic position of marine macrophytes. Therefore, the aim of the present work was to study the capacity of MGDGs, isolated from five species of marine macrophytes, to influence conformation and to enhance immunogenicity of porin from Yersinia pseudotuberculosis (YOmpF) as a model antigen of subunit vaccine based on TI-complexes. The trimeric porin was chosen for these experiments, because it was approximately two times more immunogenic than monomeric porin incorporated in TI-complexes. Immunization of mice with YOmpF within TI-complexes, comprised of different MGDGs, revealed a dependence of the immunostimulating effect of TI-complexes on the microvicosity of this glycolipid. TI-complexes comprising MGDGs from Sargassum pallidum and Ulva fenestrata with medium microviscosity induced maximal levels of anti-porin antibodies (four times higher when compared with those induced by pure porin). The adjuvant effect of TI-complexes based on other MGDGs varied by 2.8, 2.3 and 1.3 times for TI-complexes comprised of MGDGs from Zostera marina, Ahnfeltia tobuchiensis, and Laminaria japonica, respectively. MGDGs are also able to influence cytokine mechanisms of immunological regulation. DSC and spectroscopic studies showed that maximal immunostimulating effect of TI-complexes correlated with a moderate stabilizing influence of MGDGs from S. pallidum and U. fenestrata on the conformation of porin. The results obtained suggest lipid "nanofluidics" as a novel strategy for optimizing the immune response to protein antigens within lipid particulate systems.