1993 Fiscal Year Final Research Report Summary
Biosynthesis of the chitinase inhibitor allosamidin produced by Streptomyces
| Project/Area Number |
04660117
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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 |
応用微生物学・発酵学
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| Research Institution | Osaka University |
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Principal Investigator |
YAMADA Yasuhiro Osaka Univ. Fac, of Engineer. Prof., 工学部, 教授 (00011891)
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| Co-Investigator(Kenkyū-buntansha) |
SAKUDA Shohei Osaka Univ. Fac, of Engineer. Associ. Prof., 工学部, 助手 (80192087)
NIHIYA Takuya Osaka Univ. Fac, of Engineer. Associ. Prof., 工学部, 助教授 (70144441)
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| Project Period (FY) |
1992 – 1993
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| Keywords | Chitinase Inhibitor / allosamidin / Biosynthesis / Streptomyces / chitinase |
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| Research Abstract |
Allosamidin 1 is the first chitinase inhibitor produced by Streptomyces. The biosynthesis of 1, which has a novel trisaccharide structure and interesting biological activities, have been investigated.
1. a new allosamidin analog, didemethylallosamidin 3, was isolated from Streptomyces sp. Jj 9463 which is a producer of 1 and demethylallosamidin 2. ^<14>C-Labeled 1, 2 and 3 were prepared to investigate the biosythesis of 1. Comversion experiments with the labeled compounds revealed that 2 was a precursor of 1, but 3 was not incorporated. this suggests that the first N-methyl group is introduced before the cyclization of the aminooxazoline ring during the biosynthesis of 1.
2. Sllosamizoline 4 is a component of 1 and has a novel cyclopentanoid structure shich is biosynthesized form D-glucosamene. To study a mechanism of the cyclopentane ring formation of 4, feeding experiments with [4-^2H]-, [5-^2H][6-^2H_2]-D-glucosamine were carried out. ^2H NMR and Cl-MS analysis of the labeled samples indicated that loss of deuterium on C-5 and stereospecific loss of one of the two deuterium on C-6 of glucosamine occured during the biosynthesis. These results suggesed that the cyclization to from the cyclopentanoid moiety of 4 would proceed via an intermediate 6-aldehyde glucosamine derivative.
3. Two chitinases were purified form the culture filtrate of Streptomyces sp. AJ 9463. They had similar molecular masses and optimum pH rages, but showed quite different sensitivities to 1. The two chitinases and their genes might be useful probes to investigate the physiological significance of the co-production fo chitinases and its inhibitorin the strain.
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