| Project/Area Number |
12559003
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
広領域
|
|---|
| Research Institution | Gifu University |
|---|
Principal Investigator |
NAGASAWA Toru Gifu University, Engineering, Professor, 工学部, 教授 (60115904)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NAKAMURA Tetsuji Mitubishi Rayon, Institute of Yokohama, Group leader, 横浜研究所, 主任研究員
YOSHIDA Toyokazu Gifu University, Engineering, Associate Professor, 工学部, 助教授 (90220657)
NAKANISHI Kazuhiro Okayama University, Engineering, Professor, 工学部, 教授 (90026584)
|
|---|
| Project Period (FY) |
2000 – 2001
|
| Project Status |
Completed (Fiscal Year 2001)
|
| Budget Amount *help |
¥11,400,000 (Direct Cost: ¥11,400,000)
Fiscal Year 2001: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2000: ¥9,300,000 (Direct Cost: ¥9,300,000)
|
|---|
| Keywords | Pytrole-2-carboxylate decarboxylase / Indole-3-carboxylate decarboxylase / Carbon dioxide fixation / CO_2固定 / 脱炭酸酵素 / 可逆的脱炭酸酵素 / 炭酸固定酵素 |
|---|
| Research Abstract |
Due to the abundance of CO2 as the major greenhouse gas and C-C-bond-formlng properties, CO2-flxing enzymes are of high interest. Recently, it is revealed that a certain group of decarboxylases can catalyze carboxylation by their reverse reaction. We have found that pyrrole-2-carboxylase efficiently catalyzes the carboxylation of pyrrole to pyrrole-2-carboxylic acid. In addition, recently we also found that indole-3carboxylate decarboxylase catalyzes the carboxylation of indole to indole-3-carboxylate. Pyrrole-2-carboxylate decarboxylase from BacMus megaterium PRY2910 attains a balanced reaction quilibrium with an equilibrium constant of 0.3-0.4 M. Therefore, saturating amounts of KHCO3 ( 3 M ) were used leading to a shift of the reaction equilibrium towards pyrrole-2-carboxylic acid. The increased pressure supported the reverse reaction productivity 2.5-fold compared to atmospheric pressure. In a batch reactin, 300 mM pyrrole'were converted to 230 mM (25.5 g/1) pyrrole-2-carboxylate. The productivity was increased to 325 mM ( 36. 1 g/1 ) by feeding 150 mM pyrrole after 3 h to a reaction with initially 250 mM pyrrole. The bioconversion yield was limited to 77-81 % due to the reaction equilibrium. Pyrrole-2-carboxylate decarboxylase and indole-3-carboxylate decarboxlase were purified and characterized. We could find some similarity. Their gene analyzes were also carrried out.
|
