Project/Area Number |
60560219
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Fisheries chemistry
|
Research Institution | Kagawa University |
Principal Investigator |
OKAICHI Tomotoshi Fac. Agric., Kagawa University, 農学部, 教授 (90035965)
|
Co-Investigator(Kenkyū-buntansha) |
MONTANI Shigeru Fac. Agric., Kagawa University, 農学部, 助手 (30136288)
OCHI Tadashi Fac. Agric., Kagawa University, 農学部, 助教授 (00035990)
|
Project Period (FY) |
1985 – 1986
|
Project Status |
Completed (Fiscal Year 1986)
|
Budget Amount *help |
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1986: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1985: ¥1,300,000 (Direct Cost: ¥1,300,000)
|
Keywords | Iron asborption / Chattonella; Seto Inland Sea / Siderophore / Glycocalyx / グリコカリックス / 硫酸多糖 |
Research Abstract |
The facts that iron concentrations in sea water of Harima Nada, Seto Inland Sea, are much less than that required by Chattonella spp. for their growth led the present authors to assume the presence of active absorption mechanisms of iron in Chatonella spp. Cutured C.antiqua and C.marina sampled from red tide of Haima Nada were extracted with 80 % alcohol and the extracts were treated with column and thin layer chromatographies. Presence of iron chelating substances were confirmed in both C.antiqua and C.marina. One of the chelating substances of C.marina was ascertained as deferroxamine B by NMR and chromatographic techniques. Glycocalyx layer was also found around the outer membrane of Chattonella spp., and the layer was assumed to participate in iron abosorption with the acidic polysaccharides contained. Acidic polysaccharides were extracted from C.antiqua cells with <Na_2> <CO_3> and fractionated with DEAE cellulose column by stepwise gradient elution using NaCl (0.25 - 2.0 M,pH 2 and pH 12). Sulfonated polysaccharide fraction conjugates 1 atom of iron in 17 molecules of it glucose. Heavy metal contents in Chattonella spp. and other phytoplankton were also analyzed with plasma spectrometer (Hitachi 300). Based on these results, the iron absorption mechanisms are postulated to be as follows. Iron, either soluble or particulate from, is adsorbed on glycocalyx layerin conjugation with acidic polysaccharides, and, then, transferd to iron chelating substances (siderophores) excreted from cell to transport into the cell for the biochemical purposes.
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