Oxygen evolution photosynthesis

Tommos C, Hoganson CW, Di Valentin M, et al. Manganese and tyrosyl radical function in photosynthesis oxygen evolution. Curr Opin Chem Biol 1998 2 244-52. 

Brudvig, Gary W. and Crabtree. Robert H., Bioinorganic Chemistry of Manganese Related to Photosynthesis Oxygen Evolution. 37 99... 

Table 1. The effect of irradiation in PAR+UVB for 15 or 30 min. on gross photosynthesis (oxygen evolution) of several benthic marine algae from New South Wales. The rate of photosynthesis is expressed as a percentage of the rate for aigae irradiated only with PAR for the given period.

FIGURE 5. Effect of illumination in air of control and PPT treated leaves on the subsequent photosynthesis oxygen evolution at high EC023. Light response curves. 

Fig. 2. Effects of light intensity and quality, and cell concentration on the volumetric oxygen evolution rate by algal photosynthesis. Li t types and cell concentration used ( ) simulated daylight and 0.215 g L" (A) simulated daylight and 0.123 g L (A) red light and 0.123 g L" and (o) green light and 0.123 g V. ...

The action spectmm of positive and negative phototaxis of Anabaena variabilis was measured recently106). This species contains no C-phycoerythrin. Accordingly, maximum activity is found at around 615 nm (Fig. 7). In addition, in this form a second maximum occurs at around 675 nm, and a third small, but distinct, one at 440 nm, both indicating that chlorophyll a is also involved in the active light absorption (see above). The utilization via photosynthesis, however, could be excluded in this case, since the trichomes oriented themselves perfectly well to the light direction in the presence of photosynthetic inhibitors, such as DCMU and DBMIB, at concentrations in which the photosynthetic oxygen evolution was almost completely inhibited. 

Volkov AG (1989) Oxygen evolution in the course of photosynthesis molecular mechanisms. Bioelectrochem Bioenergetics 21 3-24... 

On other contribution of sonophotocatalytic reaction, it may be thought to construct the system like Photosynthesis, since oxygen evolution and carbon dioxide fixation proceed simultaneously by sonophotocataiysis. 

Chl-coated semiconductor (n-type) electrodes have thus far been studied using ZnO, CdS, and Sn02, all of which act as efficient photoanodes for converting visible light. Such Chl-sensi-tized photoanodes could be regarded as in vitro models for the photosystem II (oxygen evolution) function in photosynthesis, p-type semiconductor electrodes have not been utilized successfully to produce cathodic Chl-sensitized photocurrents with satisfactory efficiencies. On the other hand, Chl-coated metal electrode systems seem to overcome this problem. 

Van Rensen, J.J.S. (1971). Action of some herbicides in photosynthesis of Scenedesmus, as studied by their effects on oxygen evolution and cyclic photophosphorylation. Wageningen H. Veenman. 80 p. 

Britt, R.D. (1996) Oxygen evolution, Adv. Photosynth. 4 (Oxygenic Photosynthesis The Light Reactions), 137-164. 

In 1937 Robin Hill demonstrated that isolated chloroplasts, when placed in an aqueous solution in the presence of a suitable electron acceptor, can evolve oxygen in the light, a process that has become known as the Hill reaction. Oxygen evolution proceeds in the absence of CO2, suggesting that CO2 fixation and O2 evolution are separate processes, contrary to the then prevailing belief. Using lsO-labeled H20 and lsO-labeled CO2 in different experiments, Laurens Ruben and Martin Kamen showed in 1941 that the evolved O2 comes from water and not from CO2. Subsequent studies have elucidated the steps intervening between O2 evolution and CO2 fixation in photosynthesis. 

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