
doi: 10.1007/bf00935657
pmid: 1004864
The principles of biological evolution of photosynthesis are established, but the ways of chemical evolution are unclear yet. The model systems will help to elucidate the problem. Every type of photosynthesis requires photoreceptor absorbing solar radiation. We studied as photoreceptors inorganic components of Earth crust, some coenzymes and porphyrins of abiogenic and biogenic origin. By the aid of inorganic photosensitizers (TiO2, ZnO) the models of photosystems I and II were constructed. Photochemical activation of some coenzymes may serve as an intermediate step from heterotrophic 'dark' to 'light' metabolism. The further evolution led to the separation of catalytic and photosensitizing functions. Porphin, chlorin and bacteriochlorin were formed by abiogenic synthesis. Magnesium complexes of porphyrins are active being excited by light. They are capable to reversible acceptance or donation of an electron to partner molecule. Excited Mg-complexes of porphyrins (P) are capable to transfer an electron from electron-donor (D) to electron-acceptor (A) accompanied by conversion of light quanta energy into potential chemical energy. The primary electron transfer unit (D-P-A) was incorporated into primary membrane. The transition from random to anisotropic arrangement of (D-P-A) in the membrane was plausable as a step of evolution; charge translocation appeared. (D-P-A) units created in the period of chemical evolution were probably used in the course of biological evolution. The (D-P-A) units were coupled with noncyclic and cyclic electron transfer resulting in ATP formation; coupling of two (D-P-A) units led to H2O oxidation and NADP reduction in photosynthetic organisms. The improvement of pigments biosynthesis created the phenomenon of excitation energy migration from the bulk of the pigment to (D-P-A) unit, being reactive center. The models described points the plausible steps of chemical evolution; the real sequence of events will be probably disclosed in the studies of precambrian rocks and space exploration.
Light, Electrons, Pigments, Biological, Biological Evolution, Electron Transport, Oxygen, Magnesium, Photoreceptor Cells, Chlorine, Photosynthesis
Light, Electrons, Pigments, Biological, Biological Evolution, Electron Transport, Oxygen, Magnesium, Photoreceptor Cells, Chlorine, Photosynthesis
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 24 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
