Spirillum metabolism

In purified preparations of antenna complexes obtained from several phototrophic purple bacteria, mixtures of metabolically related carotenoids are usually found (Cogdell and Thomber, 1979). The sole reported exception to this rule seems to be a B880 complex of Rhodo spirillum mbmm in which only spirilloxanthin was detected, although Duysens (in Cogdell and Thomber, 1979, pp. 77) suggested that its uniform carotenoid composition could be due to the use of old bacterial cultures as the source of the... 

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