Cyanobacteria photosynthetic properties

Thomas JC and Mousseau A (1982) Phycoerythrocyanin in Oscillatoriacean strains (Cyanobacteria). Location and photosynthetic properties. Abs. 4th International Symposium on photosynthetic Prokaryotes, Bombannes France,C 29... 

Unlike the photosynthetic apparatus of photosynthetic bacteria, that of cyanobacteria consits of two photosystems, PS I and II, connected by an electron transport chain. The only chlorophyll present is chlorophyll a, and, therefore, chlorophylls b—d are not of interest in this article. Chlorophyll a is the principal constituent of PS I. Twenty per cent of isolated pigment-protein complexes contain one P700 per 20—30 chlorophyll a molecules the other 80% contain only chlorophyll a20). The physical and chemical properties of chlorophyll a and its role in photosynthesis have recently been described by Meeks77), Mauzerall75), Hoch60), Butler10), and other authors of the Encyclopedia of Plant Physiology NS Vol. 5. 

Subramaniam, A., Carpenter, E. J., Karentz, D., and Falkowski, P. G., Bio-optical properties of the marine diazotrophic cyanobacteria Trichodesmium spp. I. Absorption and photosynthetic spectra, Limnol. Oceanogr., 44, 608, 1999. 

The intermediate electron transfer between the pool of quinones accepting electrons from the RC, and the water soluble proteins donating electrons to the RC (bacterial RC and the PSI-RC) is always promoted, at least in the systems studied so far in detail, by a multiprotein complex containing cytochromes and Fe-S proteins, the so called h/ci complex. The universal presence of this type of complex in many redox chains of respiration and photosynthesis has been recognized only very recently [109]. As far as photosynthesis is concerned, complexes of this kind have been characterized in facultative photosynthetic bacteria [110] in cyanobacteria [111], and in higher plant chloroplasts [112]. All these preparations share common characteristics and composition these properties are also very similar to those of analogous complexes isolated from mitochondria of mammals and fungi [109]. 

Photosystem II (PSII) is part of the photosynthetic apparatus in cyanobacteria, algae and higher plants and catalyzes the light-induced transfer of electrons from water to plastoquinone via a set of delicately arranged cofiictors. It has a well known bindii site for diverse chemical compounds in its so-called D1 subunit and the ability to convert such a binding event into signals which can be easily detected by optical, potentiometric or amperometric systems. Due to these inherent properties PSII can be considered as a natural biosensor and has consequentially been used for the detection of herbicides and other pollutants in pilot studies. ... 

In recent years we investigated a variety of photosynthetic electron transport properties in tobacco chloroplasts and cyanobacteria (1-6). 

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