| Project/Area Number |
62570829
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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 |
Functional basic dentistry
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| Research Institution | Faculty of Dentistry, Tokyo Medical and Dental University |
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Principal Investigator |
TAKAHASHI Nobuyoshi Dept. of Microbiol., Fac. of Dent., Tokyo Med. Dent. Univ., 歯学支部, 助手 (90014258)
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| Co-Investigator(Kenkyū-buntansha) |
TSUCHIDA Nobuo Dept. of Microbiol., Fac. of Dent., Tokyo Med. Dent. Univ., 歯学部, 教授 (60089951)
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| Project Period (FY) |
1987 – 1988
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| Project Status |
Completed (Fiscal Year 1988)
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| Budget Amount *help |
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1988: ¥200,000 (Direct Cost: ¥200,000)
Fiscal Year 1987: ¥1,600,000 (Direct Cost: ¥1,600,000)
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| Keywords | Bacteroides oralis / dextranase / クローニング / Bacteroides oralis Ig4a / pGL1 |
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| Research Abstract |
Glucanases which have been reported to remove dental plaque could be used as an oral therapeutic agent. We previsously reported that Bacteroides oralis Ig4a isolated from oral flora, produced alpha-1,6-glucanase (dextranase). In the present work, we cloned a dextranase gene of B. oralis Ig4a into the HindIII site of pUC8 vector of Escherichia coli and the obtained recombinant plasmid was designated pGL1. pGL1 contained an insert of a 4.2 kilobase-pair(kb) HindIII DNA fragment derived from B. oralis Ig4a. E. coli containing pGL1 produced dextranase activity which was mainly localized in the cytoplasmic fration. Analyses of deletion and insertion plasmids of pGL1 and DNA sequencing revealed that the fragment lacked its own promoter and further that a long open reading frame (ORF) started at one of the ends and finished around the middle of the insert. The ORF could encode a protein of 82 kd. The nucleotide sequence was verified by the result that the C-terminal 3 amino acid sequence deduced from the nucleotide sequence matched with that of 44 kd dextranase purified from B. oralis Ig4a, although the organism produced a dextranase of 105 kd species with the largest molecular weight. The above results all together suggest that the cloned fragment is a 3' portion of the dextranase gene and that in B. oralis Ig4a dextranase was produced as a 105 kd protein species and processed to a 44 kd species by unknkown proteases.
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