Photosynthesis-related protein

During the 1960s, research on proteins containing iron—sulfur clusters was closely related to the field of photosynthesis. Whereas the first ferredoxin, a 2[4Fe-4S] protein, was obtained in 1962 from the nonphotosynthetic bacterium Clostridium pasteurianum (1), in the same year, a plant-type [2Fe-2S] ferredoxin was isolated from spinach chloroplasts (2). Despite the fact that members of this latter class of protein have been reported for eubacteria and even archaebacteria (for a review, see Ref. (3)), the name plant-type ferredoxin is often used to denote this family of iron—sulfur proteins. The two decades... 

In contrast to common usage, the distinction between photosynthetic and respiratory Rieske proteins does not seem to make sense. The mitochondrial Rieske protein is closely related to that of photosynthetic purple bacteria, which represent the endosymbiotic ancestors of mitochondria (for a review, see also (99)). Moreover, during its evolution Rieske s protein appears to have existed prior to photosynthesis (100, 101), and the photosynthetic chain was probably built around a preexisting cytochrome be complex (99). The evolution of Rieske proteins from photosynthetic electron transport chains is therefore intricately intertwined with that of respiration, and a discussion of the photosynthetic representatives necessarily has to include excursions into nonphotosynthetic systems. 

What are the most central and fundamental problems of biology today They are questions like What is the sequence of bases in the DNA What happens when you have a mutation How is the base order in the DNA connected to the order of amino acids in the protein What is the structure of the RNA is it single-chain or double-chain, and how is it related in its order of bases to the DNA What is the organization of the microsomes How are proteins synthesized Where does the RNA go How does it sit Where do the proteins sit Where do the amino acids go in In photosynthesis, where is the chlorophyll how is it arranged where are the carotenoids involved in this thing What is the system of the conversion of light into chemical energy ... 

Of the other blue copper proteins, only amicyanin shows a similar effect of pH (79), and a TpK of 7.18 has been obtained for the Cu(I) state. As with plastocyanin, no corresponding effect is observed for Cu(II) amicyanin, at least down to pH 4.5. The physiological relevance in the case of both proteins is at present unclear. Because in photosynthesis the pH of the inner thylakoid is less than 5.0, one possibility is that this is related to proton transport. Alternatively, it quite simply may be a control mechanism for electron transport. 

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