Abstract 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 ($ TiO_{2} $, 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 evolutior 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 plausible 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 $ H_{2} $O 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 creative 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.
Chemical evolution of photosynthesis
Origins of life ; 7 , 2
1976
Article (Journal)
English
Local classification TIB: | 535/3908/4290 | |
BKL: | 44.71 Verkehrsmedizin |
Pathways of chemical evolution of photosynthesis
Online Contents | 1974
|Some aspects of the early evolution of photosynthesis
Elsevier | 1991
|Some remarks on the origin and evolution of photosynthesis
Online Contents | 1984
|Leaf Absorbance and Photosynthesis
British Library Conference Proceedings | 1994
|