Influence of Carotenoids on the Infra-Red Spectrum of Bacteriochlorophyll in Chromatium

Properties of Chromatium Subchromatophore Particles Obtained by Treatment with Triton X-100*

“…The existence of three BChl forms in vivo, as evidenced by the near-infrared bands, has been interpreted in terms of either BChl-protein interaction (Duysens, 1952), carotenoid-BChl interaction (Izawa et al, 1963;Wassink et al, 1939;Bergeron and Fuller, 1959;Clayton and Arnold, 1961), or different aggregated forms of BChl (Krasnovskii et al, 1952). The present investigation does not give direct information on this important point.…”

MacroMolecular Complexes

“…2. The buffered 0.5M sucrose medium is a recent refinement which was designed to maintain the physiological relationship between the carotenoid pigments and the bacteriochlorophyll (Bergeron, 1958;Bergeron and Fuller, 1959;. After the chromatophores have sedimented, the preparation is washed by resuspension and recen-BACTERIA ARE SUSPENDED IN 40 ML OF 0.…”

“…It should be noted that the carotenoids occur as a variable mixture of several types, particularly lycopene, spirilloxanthin, and lycoxanthin ( Goodwin and Land, 1956 ) . It is also possible to interfere with carotenoid synthesis by treatment with diphenylamine (Goodwin and Osman, 1954) and obtain chromatophores which appear to totally lack the colored carotenoids ; Bergeron and Fuller, 1959); however, poorly colored precursors appear to be present instead (reviewed by ). Since the carotenoid :bacteriochlorophyll ratio observed above agrees with the ratio reported by , and with the maximum value observed by in Rhodopseudomonas spheroides, it seems safe to assume that these chromatophores also contained about the maximum amount of colored carotenoids.…”

Macromolecular Complexes

“…2. The buffered 0.5M sucrose medium is a recent refinement which was designed to maintain the physiological relationship between the carotenoid pigments and the bacteriochlorophyll (Bergeron, 1958; Bergeron and Fuller, 1959; (-20°C) for long periods without significant loss in enzymic activity or alteration in the over-all phvsicochemical properties. Physicochemical Properties.…”

“…It should be noted that the carotenoids occur as a variable mixture of several types, particularly lycopene, spirilloxanthin, and lycoxanthin ( Goodwin and Land, 1956 ) . It is also possible to interfere with carotenoid synthesis by treatment with diphenylamine (Goodwin and Osman, 1954) and obtain chromatophores which appear to totally lack the colored carotenoids ; Bergeron and Fuller, 1959); however, poorly colored precursors appear to be present instead (reviewed by ). Since the carotenoid :bacteriochlorophyll ratio observed above agrees with the ratio reported by Newton and Newton (1957), and with the maximum value observed by in Rhodopseudomonas spheroides, it seems safe to assume that these chromatophores also contained about the maximum amount of colored carotenoids.…”