Photobacterium leiognathi symbiotic

The (Cu,Zn)-SOD is found in the cytosol of eukaryotic cells and in the intermembrane space of mitochondria, as observed with chicken liver and also in chloroplasts, as shown with spinach and mustard leaves. A (Cu,Zn)-SOD has also been isolated from a prokaryote Photobacterium leiognathi. Could this symbiotic bacterium have borrowed the gene(s) from its host, the Pony fish, although two different subunits (Af 15,000 and 17,000) were reported for the bacterial enzyme A (Cu,Zn)-SOD was furthermore detected in Paracoccus denitrificans... 

In contrast to the bacterial-squid story, little is known about the horizontal transfer of luminous symbionts in bacteria-fish symbioses. Recently, however, we successfully raised Leiognathus nuchalis, pony fish juveniles, and infected them with symbiotic Photobacterium leiognathi. Juvenile L nuchalis raised separately from adults are apo-symbiotic and therefore not luminous. When the juveniles were kept with adults, a significant number became infected and luminescent. These results strongly support, the horizontal transfer of expelled P. leiognathi. 

RFLP ANALYSIS OF THE LUX A GENES OF PHOTOBACTERIUM LEIOGNATHI ISOLATES DERIVED FROM THE SYMBIOTIC LIGHT ORGAN OF LEIOGNATHID FISH, LEIOGNATHUS RIVULATUS... 

Dunlap PV, Steinman, HM. Strain variation in bacteriocuprein superoxide dismutase from symbiotic Photobacterium leiognathi. J Bacteriol 1986 165 393-8. 

Dunlap PV, Jiemjit A, Ast JC, Pearce MM, Marques RR, Lavilla-Pitogo CR. Genomic polymorphism in symbiotic populations of Photobacterium leiognathi. Environ Microbiol 2004 6 145-58. 

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