2001 Fiscal Year Final Research Report Summary
Regulation of Acetate Metabolism in Escherichia coli
| Project/Area Number |
12660088
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
応用微生物学・応用生物化学
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| Research Institution | Meijo University |
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Principal Investigator |
ICHIHARA Shigeyuki Meijo University, Agriculture, Professor, 農学部, 教授 (30092993)
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| Project Period (FY) |
2000 – 2001
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| Keywords | Escherichia coli / acetate metabolism / ack-pta / acs / ilvB |
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| Research Abstract |
Industrial fermentation of amino acids and organic acids are performing with the understand of the relationships between complex metabolic pathways. In this work, I suppose to improve of Escherichia coli to acetate non-productive strain in spite of the presence of excess carbon sources in a medium.
Utilization of acetate m Escherichia coli is largely depend on the phosphotransacetylase-acetate kinase (Pta-Ack) pathway. A knock out strain of the pathway could still grow on a synthetic medium containing acetate as a sole carbon source. We revealed that the growth depend on acetyl-CoA synthetase (acs) gene. Then ack-pta and acs double deletion mutant was constructed. Double deletion mutants could not grow on a synthetic medium containing acetate as a sole carbon source. However, the mutant still have acetate productivity. From this strain we found a psudorevertant which can regrow on acetate medium.
Mutants which can not grow on acetate medium was rescreened by using transposon Tn 5(km). The third gene concerned acetate metabolism thus found was the acetohydroxy acid synthase I (ilvB) gene. Triple deletion mutants constructed can still produce acetate in a medium containing excess carbon sources although the production speed was greatly decreased.
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