Determination of double decker sandwich structured La-substituted chlorophyll a by EXAFS.
As a representative natural porphyrin derivative, it is interesting to know the chemical form of lanthanide in chlorophyll a. We select the natural fern dicranopteris dichotoma, the most lanthanide-concentrated plant known, to isolate the chlorophyll a for our study. It is found by EXAFS that lanthanum substitutes in the magnesium position in chlorophyll and coordinates with the porphyrin ring. The lanthanum is seen to have a similar coordination structure to a sandwich-type lanthanide complex, with the La surrounded by eight nitrogen atoms from two porphyrin rings with average La-N bond length of 2.65 A.
Tao
Y
Y
Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, China. taoy@alpha02.ihep.ac.cn
Zhao
G
G
Yang
J
J
Ikeda
S
S
Jiang
J
J
Hu
T
T
Chen
W
W
Wei
Z
Z
Hong
F
F
D002734:Chlorophyll / Q000737:chemistry*; D000077194:Chlorophyll A; D007811:Lanthanum / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry; D015394:Molecular Structure; D010944:Plants / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission / Q000379:methods
D002734:Chlorophyll; D007811:Lanthanum; D008274:Magnesium; D000077194:Chlorophyll A