Carotenoids from the aerobic photosynthetic bacterium, Erythrobacter longus: ?-Carotene and its hydroxyl derivatives

Phylogenetic Positions of Novel Aerobic, Bacteriochlorophyll a-Containing Bacteria and Description of Roseococcus thiosulfatophilus gen. nov., sp. nov., Erythromicrobium ramosum gen. nov., sp. nov., and Erythrobacter litoralis sp. nov.

“…Both species contain only the core antenna complex that absorbs at 870 nm. A similar carotenoid pattern has also been found in "Erythromicrobium ramosum" (34)(35)(36)44). This species, however, contains two light-harvesting complexes, LHI (B870) and LHII (B798-832).…”

Two Distinct crt Gene Clusters for Two Different Functional Classes of Carotenoid in Bradyrhizobium

“…This is certainly also the case for other aerobic photosynthetic bacteria, such as E. longus, which have been reported to produce different classes of carotenoids (4,10). One can wonder what is the physiological and evolutionary basis for such a complex carotenoid composition found specifically in some aerobic photosynthetic bacteria.…”

“…Indeed most strains synthesize, in addition to the carotenoids involved in photosynthesis such as spirilloxanthin, a large amount of unusual carotenoid molecules (3). The most striking complexity is observed for Erythrobacter species such as Erythrobacter longus or Erythrobacter ramosum, which have been reported to produce about 20 different carotenoids (4,5). Another example comes from various strains of photosynthetic Bradyrhizobium, symbionts of Aeschynomene (6), which synthesize, in addition to spirilloxanthin, large amounts of canthaxanthin of unknown function (7,8).…”

Elucidation of the Erwinia uredovora carotenoid biosynthetic pathway by functional analysis of gene products expressed in Escherichia coli

“…A yellow-orange carotenoid pigment (2.2 mg/g of dry weight) accumulated by E. coli(pCAR25delB) carrying ORF-A, ORF-C, ORF-D, ORF-E, and ORF-F proved to be identical to zeaxanthin [(3R,3'R)-1,1-carotene-3,3'-diol] by its TLC, UV-visible, mass, 'H-NMR, 13C-NMR, and circular dichroism spectral data (24), corresponding to the carotenoid of Rf 0.93 in E. coli(pCAR25). An orange carotenoid pigment (2.0 mg/g of dry weight) accumulated by E. coli(pCAR16) or E. coli(pCAR16delB) proved to be identical to 13-carotene (all-trans-P,P-carotene) by TLC, UV-visible, mass, and 13C-NMR analyses, using the commercial authentic sample (Sigma).…”