| Project/Area Number |
06640737
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Inorganic chemistry
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| Research Institution | Fukuyama University |
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Principal Investigator |
HIROSE Junzo Faculty of Engineering, Fukuyama University Associate Prof., 工学部, 助教授 (70080215)
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| Co-Investigator(Kenkyū-buntansha) |
IWAMTO Hiroyuki Faculty of Engineering, Fukuyama University Assistant Prof., 工学部, 講師 (90213321)
HIROMI Keitaro Faculty of Engineering, Fukuyama University Professor, 工学部, 教授 (50025425)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1995: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1994: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | Multi-copper enzyme / Electron transfer reaction / Copper enzyme / 酸化還元電位 / 配位残基 |
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| Research Abstract |
Bilirubin oxidase is the enzyme that catalyses the oxidation of bilirubin to biliverudin and a multi-copper enzyme containing type 1, type 2, and type 3 copper in the ratio of 1 : 1 : 2, respectively. Ferrocyanide ion (Fe (CN) _6^<4->) is a good substrate for bilirubin oxidase. Michaelis-Menten constant (K_m) and molar activity (K_<cat>) are 3.0*10^<-3>M and 300 sec^<-1>. Cr (CN) _6^<3-> that is structually similar to Fe (CN) _6^<4-> inhibits competitively the oxidation of Fe (CN) _6^<4->. The inhibition constant of Cr (CN) _6^<3-> is 3.0*10^<-3> M that is almost same value of K_m of Fe (CN) _6^<4->2. These results indicate that Cr (CN) _6^<3-> binds the binding site of Fe (CN) _6^<4-> in bilirubin oxidase. The gene of bilirubin oxidase was cloned and the nucleotide sequence of bilirubin oxidase has been determined. On the basis of the nucleotide sequence of bilirubin oxidase, the complete amino acid sequence of bilirubin oxidase has been determined. The amino acid residues that coordinate to cupric ions were decided and those that are around substrate binding site also are also guessed.
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