Since the first experimentally derived atomic scale models of DNA and protein were reported 60 years ago, many thousands of atomic coordinates have been deposited in the protein data bank archives (wwPDB ), which currently contain more than 149,000 entries. Indeed, before the arrival of experimentally determined structures of DNA and proteins, ideas on how they might appear at the atomic scale were strongly influenced by X-ray structures of inorganic molecules such as crystalline salt. In other words, the presence of liquid bulk water surrounding the macromolecules of life gives the entropic term the decisive weight in the energetics that govern their overall structure-an important link for understanding them.įor understanding the properties of the macromolecules of life, atomic scale structures are key. Together these minimize the decrease in entropy that is caused by the ordering of water through the exposure of their hydrophobic groups to bulk water. Despite their very different structures and compositions, the gross structure of all three macromolecules of life is determined by their amphiphilic nature and their chemical environment of liquid water.
And for a long time, it was doubted whether general statements describing common properties of the biomembrane could be made as such.
Owing to this, the fact that biomembranes are as fundamental to life as DNA/RNA and proteins might be overlooked. These are no linear polymers rather, they are composed of a wide diversity of many single amphiphilic lipid molecules forming a volume enclosing 3D structure whose architecture is not encoded in genetic information. DNA and proteins are not only linked via the mRNA but also by the fact that both are linear polymers that assemble into 3D structures which consist of repeating units of only four kinds of nucleic acids or only 20 different kinds of amino acids. The three key macromolecules of life are the oligomers of nucleic acids, that is DNA and RNA, oligomers of amino acids, that is proteins, and a multitude of lipids in the aggregate form of cell membranes.
0 kommentar(er)
