Time-dependent self-assembly of 31-epimerically pure and mixed zinc methyl bacteriopheophorbides-d in an aqueous THF solution.
The self-aggregation process of 3(1)-epimerically pure and mixed zinc methyl bacteriopheophorbides-d (ZMBPhes-d) was examined by stopped-flow technique. A 33(v/v)% tetrahydrofuran (THF) - water solution of ZMBPhe-d was rapidly mixed with a 7(v/v)% THF - water solution to form a chlorosome-type aggregate with a red-shifted Qy band around 700 nm. We observed a rapid autocatalytic aggregation in a subsecond time scale. Aggregates of the 3(1)R epimer increased with a change in the Qy absorption maximum from 698 to 705 nm, suggesting that small aggregates formed as intermediate species. In addition, the rate of aggregation was dependent on the stereochemistry at the 3(1)-position of ZMBPhe-d; the 3(1)R epimer self-aggregated more rapidly than the 3(1)S epimer.
Miyatake
Tomohiro
T
Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga, 520-2194, Japan. miyatake@rins.ryukoku.ac.jp
Shitasue
Kyouhei
K
Omori
Yushi
Y
Nakagawa
Kazuya
K
Fujiwara
Manabu
M
Matsushita
Takayuki
T
Tamiaki
Hitoshi
H
D001429:Bacteriochlorophylls / Q000737:chemistry*; D005663:Furans; D008745:Methylation; D015394:Molecular Structure; D012996:Solutions / Q000737:chemistry; D013057:Spectrum Analysis; D013997:Time Factors; D017967:Zinc Compounds / Q000737:chemistry*
D001429:Bacteriochlorophylls; D005663:Furans; D012996:Solutions; D017967:Zinc Compounds; C018674:tetrahydrofuran