Photoelectron transport particle

There are many similarities between the photoelectron transport particle from photosynthesis, the quantasome, and the basic electron transport particle involved in oxidative phosphorylation in nonphotosynthetic cells. The latter particle, found in mitochondria and sometimes called the elementary particle or oxosome, is also probably a high molecular weight particle with dimensions in the order of 100 to 200 A. It contains a complement of cytochromes, non-heme iron proteins, quinones, etc., and performs the transport of electrons coupled to the formation of ATP. Thus, one can make a strong case for the evolutionary relationship between the basic oxidative electron transport particle and the photoelectron transport particle. Speculations as to which one came first in evolution are dependent upon what one assumes to have been the environmental conditions under which the evolution occurred. 

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