The major carotenoid in all known species of heliobacteria is the C30 carotenoid 4,4'-diaponeurosporene, not neurosporene.
The carotenoids of five species of heliobacteria (Heliobacillus mobilis, Heliophilum fasciatum, Heliobacterium chlorum, Heliobacterium modesticaldum, and Heliobacterium gestii) were examined by spectroscopic methods, and the C30 carotene 4,4'-diaponeurosporene was found to be the dominant pigment; heliobacteria were previously thought to contain the C40 carotenoid neurosporene. In addition, trace amounts of the C30 diapocarotenes diapolycopene, diapo-zeta-carotene, diapophytofluene, and diapophytoene were also found. Up to now, diapocarotenes have been found in only three species of chemoorganotrophic bacteria, but not in phototropic organisms. Furthermore, the esterifying alcohol of bacteriochlorophyll g from all known species of heliobacteria was determined to be farnesol (C15) instead of the usual phytol (C20). Heliobacteria may be unable to produce geranylgeranyol (C20).
Takaichi
S
S
Biological Laboratory, Nippon Medical School, 297, Kosugi-cho 2, Nakahara, Kawasaki 211, Japan. takaichi@nms.ac.jp
Inoue
K
K
Akaike
M
M
Kobayashi
M
M
Oh-oka
H
H
Madigan
M T
MT
D001419:Bacteria / Q000737:chemistry; D001429:Bacteriochlorophylls / Q000032:analysis / Q000302:isolation & purification; D002338:Carotenoids / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification*; D005204:Farnesol / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000737:chemistry* / Q000378:metabolism; D015394:Molecular Structure; D010836:Phytol / Q000302:isolation & purification
D001429:Bacteriochlorophylls; D010836:Phytol; D002338:Carotenoids; D005204:Farnesol; C008604:neurosporene