Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Osaka University|
MATSUBARA Hiroshi Osaka Univ., Fac.Sci., Dept.Biol., Professor, 理学部, 教授 (00028242)
MALKIN Richard Univ. California, Berkeley, Dept. Plant Biology, Professor, Berkeley・Dept. Plant Biol, Prof.
BUCHANAN Bob.b. Univ. California, Berkeley, Dept. Plant Biology, Professor, Berkeley・Dept. Plant Biol, Prof.
OH-OKA Hirozo Osaka Univ., Fac.Sci., Dept.Biol., Associate Researcher, 理学部, 助手 (30201966)
SAEKI Kazuhiko Osaka Univ., Fac.Sci., Dept.Biol., Associate Researcher, 理学部, 助手 (40201511)
WADA Keishiro Kanazawa Univ., Fac.Sci., Dept.Biol., Professor, 理学部, 教授 (70028174)
RICHARD Malk Univ.of California, Berkeley・Dept.of Plan, Professor
BOB B Buchan Univ.of California, Berkeley・Dept.of Plan, Professor
高橋 康弘 大阪大学, 理学部, 助手 (10154874)
|Project Period (FY)
1992 – 1993
Completed(Fiscal Year 1993)
|Budget Amount *help
¥7,800,000 (Direct Cost : ¥7,800,000)
Fiscal Year 1993 : ¥3,900,000 (Direct Cost : ¥3,900,000)
Fiscal Year 1992 : ¥3,900,000 (Direct Cost : ¥3,900,000)
|Keywords||ferredoxin / iron-sulfur cluster / Green sulfur bacteria / reaction center / FNR / isoenzyme / thioredoxin / Rieske protein / ndh遺伝子 / 光化学系 複合体 / 光化学反応中心 / 藍藻|
Saeki et al. have constructed mutated fdxN of R. capsulatus with gene-engineering techniques. They identified cysteine residues essential to activity. With EPR spectroscopy, the spin interaction was found to be strongly affected by the amino acid residues around Fe-S clusters. He also demonstrated that the structures of fdxA product around [3Fe-4S] cluster and carboxyl terminal region were important to function physiologically.
Oh-oka et al. have succeeded in purifying the Chlorobium reaction center complex (CRC-2) made of two subunits, that is, the core protein (68kDa) and cytochrome c551(21kDa), respectively. Laser flash photolysis revealed the primary charge separation, followed by the delayed fluorescence concomitant with the formation of P840^T. They also have cloned the cytochrome c551 gene, and intend to construct transformation system in Chlorobium.
Wada have isolated two FNR isoenzymes from radish leaf and root. Antibodies against them were raised in rabbits. Each antibody showed specific reactivity and had no cross-reactivity. The antibodies distinguished the enzyme forms from roots and leaves of radish as well as other flowering plants. The FNR isoenzymes showed organ-specific distribution.
Buchanan reported that the level of thioredoxin in the endosperm might be under hormonal control during germination. He also demonstrated that spinach thioredoxin m inhibits DNA synthesis in fertilized Xenopus eggs.
Malkin have recently cloned the petC, which encoded Rieske protein. He intends to construct site-directed mutagenesis of the petC in order to study the cyclic electron transport with EPR technique.