The discovery of the DNA double helix made clear that genes are functionally defined parts of DNA molecules, and that there must be a way for cells to translate the information in DNA to specific amino acids, which make proteins. The application of physics and chemistry to biological problems led to the development of molecular biology, which is particularly concerned with the flow and consequences of biological information from DNA to proteins. The discovery had a major impact on biology, particularly in the field of genetics, enabling later researchers to understand the genetic code. The article presents a simple and elegant solution, which surprised many biologists at the time who believed that DNA transmission was going to be more difficult to deduce and understand. This mystery was the question of how it is possible that genetic instructions are held inside organisms and how they are passed from generation to generation. This article is often termed a "pearl" of science because it is brief and contains the answer to a fundamental mystery about living organisms. 6, 1938– 1946 (2000).Diagramatic representation of the key structural features of the DNA double helix. Template-induced and molecular recognition-directed hierarchical generation of supramolecular assemblies from molecular strands. 1H-NMR analysis of four species in ethanol. Spatial structures of gramicidin A in organic solvents. The double ππ5.6 helix of gramicidin A predominates in unsaturated lipid membranes. The aggregation of gramicidin A in solution. Solvophobically driven folding of nonbiological oligomers. Encoded helical self-organization and self-assembly into helical fibers of an oligoheterocyclic pyridine-pyridazine molecular strand. Helicity coding: Programmed molecular self-organization of achiral nonbiological strands into multiturn helical superstructures: synthesis and characterization of alternating pyridine-pyrimidine oligomers. Designed self-generation of an extended helical structure from an achiral polyheterocyclic strand. Hydrogen-bonding motifs in the crystals of secondary diamides with 2-amino-6-methyl and 2,6-diaminopyridine subunits. Hydrogen bonded antiparallel beta-strand motifs promoted by 2,6-bis(carbamoylpeptide)pyridine. Novel molecular scaffolds-formation of helical secondary structure in a family of oligoanthranilamides. Novel folding patterns in a family of oligoanthranilamides: Non-peptide oligomers that form extended helical secondary structures. Ruthenium complexes of a simple tridentate ligand bearing two ‘distal’ pyridine bases. Self-assembly of a double-helical complex of sodium. Self-assembly of a circular double helicate. DNH Deoxyribonucleohelicates-self-assembly of oligonucleosidic double-helical metal complexes. Self-assembly of disk-shaped molecules to coil-coil aggregates with tunable helicity. X-ray and energy calculation studies on the packing-mode of double-stranded helicies of isotactic poly(methyl methacrylate). Three-dimensional structure at 0.86 Å of the uncomplexed form of the transmembrane ion channel peptide gramicidin A. The double-stranded right-handed antiparallel β-helix in the structure of t-Boc-(L-Phe-D-Phe)4-OMe. The bent conformations leading to the helical shape of the molecules result from intramolecular hydrogen bonding within 2′-pyridyl-2-pyridinecarboxamide units 8, 9, 10, 11, 12, with extensive intermolecular aromatic stacking stabilizing the double-stranded helices that form through dimerization.ĭi Blasio, B., Benedetti, E., Pavone, V. Here we describe a family of oligomeric molecules with bent conformations, which exhibit dynamic exchange between single and double molecular helices in solution, through spiral sliding of the synthetic oligomer strands. A third mode of non-covalent interaction, coordination of organic ligands to metal ions 5, 6, 7, can give rise to double, triple and quadruple helices, although in this case the assembly is driven by the coordination geometry of the metal and the structure of the ligands, rather than by direct inter-strand complementarity. Some synthetic polymers 3 and self-assembled fibres 4 have double-helical winding induced by van der Waals interactions. Known examples include duplex formation through base-pair-specific hydrogen bonding and stacking, as found in nucleic acids and their analogues, and polypeptides composed of amino acids with alternating L and D configurations 1, 2. Synthetic single-helical conformations are quite common, but the formation of double helices based on recognition between the two constituent strands is relatively rare.
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