Biological photosynthetic

Department of History and Philosophy of Science, Department of Biology, Photosynthetic Bacteria Group, Indiana University, Bloomington, IN 47405, USA... 

Utilization of solar energy Antibiotics are produced by utilizing agricultural products which are obtained from biological photosynthetic conversion of solar energy. The production of antibiotics does not much consume the stored energy such as oil and coal. 

Fig. 1 Schematic drawing of hydrogen peroxide photoproduction by the biological photosynthetic apparatus with electrons either from water or from an exogenous electron donor. A redox catalyst (RC) transfers electrons from the terminal acceptor of photosystem I to molecular oxygen.

The latter is almost certainly involved in an interesting thermal equilibrium (22), which has been observed in both pyridine and toluene solutions. When [Mn4L8] (L = 243) (Section 41.3.5.3.ii) was treated with py, purple crystals [MnlvL2py2] -2py (L = 242) were obtained. An X-ray analysis738 proved the Mnlv/catecholate formulation Mn—O = 1.854(2) and Mn—N = 2.018(3)A, and a spectrophotometric study of the equilibrium (22) showed that the Mnlv form prevails at low temperature in the solutions. There seems to be a real possibility that some such redox changes may offer an explanation of the role of Mn in biological photosynthetic water oxidation. 

In this chapter results of the picosecond laser photolysis and transient spectral studies on the photoinduced electron transfer between tryptophan or tyrosine and flavins and the relaxation of the produced ion pair state in some flavoproteins are discussed. Moreover, the dynamics of quenching of tryptophan fluorescence in proteins is discussed on the basis of the equations derived by the present authors talcing into account the internal rotation of excited tryptophan which is undergoing the charge transfer interaction with a nearby quencher or energy transfer to an acceptor in proteins. The results of such studies could also help to understand primary processes of the biological photosynthetic reactions and photoreceptors, since both the photoinduced electron transfer and energy transfer phenomena between chromophores of proteins play essential roles in these systems. 

Two groups of substituted l,4-ben2oquiaones are associated with photosynthetic and respiratory pathways the plastoquinones, eg, plastoquinone [4299-57-4] (34), and the ubiquinones, eg, ubiquinone [1339-63-5] (35), are involved in these processes. Although they are found in all living tissue and are central to life itself, a vast amount remains to be learned about their biological roles. 

Algae A group of photosynthetic organisms that range from microscopic size to a length of 20 m. They supply oxygen and consume nutrients in several different processes for biological waste treatment. 

A major biological sink for CO9 that is often overlooked is the calcium carbonate shells of corals, molluscs, and Crustacea. These invertebrate animals deposit CaCOa in the form of protective exoskeletons. In some invertebrates, such as the sderaetinians (hard corals) of tropical seas, photosynthetic dinoflagellates (kingdom Protoctista) known as zooxanthellae live within the ani-... 

Much effort has also been directed toward mimicking electron transfer on natural photosynthetic systems. Recently, the group of Harada has been able to prepare monoclonal antibodies against metallo porphyrins and show that the biological edifice can control photoinduced electron transfer from the porphyrin to organic acceptor molecules in solution. As it was important to design a biomolecule able to accommodate not only the metalloporphyrin unit but also organic substrates, Harada recently used a hexacoordinated phosphorus... 

Systems like SFg [39, 40], HjO [41], CH3OH [41], and CBr4/C6Hi2 [42] have been examined using this technique. Three recent papers on ruthenium (11) tris-2, 2 -bipyridine, or [Ru (bpy)3] " [43], on photosynthetic O2 formation in biological systems [44], and on photoexcitation of NITPP — L2 [45] in solution also merit attention. Theoretical work advanced at the same time. Early approaches are due to Wilson et al. [46], whereas a statistical theory of time-resolved X-ray absorption was proposed by Mukamel et al. [47, 48]. This latter theory represents the counterpart of the X-ray diffraction theory developed in this chapter. 

This chapter brings together information concerning structural features, spectral characteristics, distributions, and functions of major chlorophylls in photosynthetic organisms. Other topics discussed include biosynthesis and degradation in senescent plants and ripening fruits and potential biological properties of chlorophylls. 

The reduction of ketones, aldehydes, and olefins has been extensively explored using chemical and biological methods. As the latter method, reduction by heterotrophic microbes has been widely used for the synthesis of chiral alcohols. On the contrary, the use of autotrophic photosynthetic organisms such as plant cell and algae is relatively rare and has not been explored because the method for cultivation is different from that of heterotrophic microbes. Therefore, the investigation using photosynthetic organisms may lead to novel biotransformations. 

TRIR methods have also found utility in the elucidation of reaction mechanisms involved in biological systems, most notably photosynthetic and respiratory proteins. In addition, TRIR spectroscopy has also been used to enhance our understanding of the dynamics of protein folding processes. ... 

However, process (6.5.5) cannot be a universal photosynthetic process because H2S is unstable and is not available in sufficient quantities in nature. Water is the only substance that can be used in the reduction of carbon dioxide whose presence in nature is independent of biological processes. 

It is therefore important to bear in mind the dependency of the carotenoid spectrum upon properties of the environment for in vivo analysis, which is based on the application of optical spectroscopies. This approach is often the only way to study the composition, structure, and biological functions of carotenoids. Spectral sensitivity of xanthophylls to the medium could be a property to use for gaining vital information on their binding sites and dynamics. The next sections will provide a brief introduction to the structure of the environment with which photosynthetic xanthophylls interact—light harvesting antenna complexes (LHC). 

Such a process can naturally be expected to play a certain part in the mechanism of directed energy transport in biological systems, in particular, in the transfer of absorbed energy from the antenna chlorophyll molecules to the reactive center in the photosynthetic system of plants. In Ref. [30], energy exchange between molecules of the photosynthetic pigments chlorophyll a and pheophytin a was studied experimentally with pigments introduced into the polar matrix. 

The isotopic composition of carbon in carbonaceous organic material (kerogen) from ancient sedimentary rocks gives information on whether photosynthetic organisms were present during rock formation or not. It can also provide information on biological activities if cellular structures had already been destroyed. Sulphur can be used in a similar way (Schopf, 1999). 

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