| Project/Area Number |
16510061
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Environmental technology/Environmental materials
|
|---|
| Research Institution | Kumamoto University |
|---|
Principal Investigator |
SHIGEMATSU Toru Kumamoto University, Graduate School of Science and Technology, Assistant Professor, 大学院・自然科学研究科, 助手 (10315286)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MORIMURA Shigeru Kumamoto University, Graduate School of Science and Technology, Associate Professor, 大学院・自然科学研究科, 助教授 (20230146)
KIDA Kenji Kumamoto University, Graduate School of Science and Technology, Associate Professor, 工学部, 教授 (00195306)
|
|---|
| Project Period (FY) |
2004 – 2005
|
| Project Status |
Completed (Fiscal Year 2005)
|
| Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,900,000)
Fiscal Year 2005: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2004: ¥2,400,000 (Direct Cost: ¥2,400,000)
|
|---|
| Keywords | Biotechnology / Applied Microbiology / Gene / phylogenetic evolution / Reutilization of waste / メタン発酵 / メタン生成古細菌 / プロピオン酸酸化細菌 / 遺伝子プローブ / ack遺伝子 / 密度勾配遠心 / 系統解析 / 細胞間電子伝達系 |
|---|
| Research Abstract |
Under methanogenic conditions, complex organic matters are degraded in a series metabolism by a number of microorganisms of different metabolic abilities. There are several reaction steps, where syntrophic associations between Bacteria and Arcahea are involved. The mechanism of these syntrophic associations has been partly explained based on interspecies electron transport system, although this system remains unknown in detail. In this study we constructed mesophilic anaerobic chemostat cultivations of enriched methanogenic consortia degrading (i) acetate, (ii) propionate or (iii) bovine serum albmin (BSA). Using these chemostats, we analyzed the microbial community structures to understand the syntrophic associations for degrading these substrates and the interspecies electron transport system.
Acetate conversion pathway was analyzed using RT-PCR and ^<13>C-labeled acetates. Syntrophic oxidation by acetate oxidizing syntrophs belonging to Firmicutes and hydrogenotrophic methanogens Methanoculleus was suggested to occupy a primary pathway in total methanogenesis at the low dilution rate of 0.025 d^<-1>. In the propionate degradation chemostat, Syntrophobacter relatives and Pelotomaculum relatives were suggested to syntrophically associate with Methanoculleus and/or Methanospirillum and to play the central roles for propionate degradation at the low dilution rate of 0.01 d^<-1> and the high dilution rate of 0.3 d^<-1>, respectively. In the BSA-degrading chemostat, the genus Aminobacterium, was suggested to associate with Methanoculleus and play a central role in amino acid degradation under the condition of Ni^<2+> and Co^<2+> addition, which allowed increased population of methanogenic Archaea.
|
