Project/Area Number |
16207001
|
Research Category |
Grant-in-Aid for Scientific Research (A)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Ecology/Environment
|
Research Institution | Research Institute for Humanity and Nature (2005-2006) Kyoto University (2004) |
Principal Investigator |
KAWABATA Zen'ichiro Research Institute for Humanity and Nature, Research Department, Professor, 研究部, 教授 (80108456)
|
Co-Investigator(Kenkyū-buntansha) |
NASU Masao Osaka University, Graduate School of Pharmacology, Professor, 大学院薬学研究科, 教授 (90218040)
ENDO Ginro Tohokugakuin University, Faculty of Engineering, Professor, 工学部, 教授 (80194033)
|
Project Period (FY) |
2004 – 2006
|
Project Status |
Completed (Fiscal Year 2006)
|
Budget Amount *help |
¥49,400,000 (Direct Cost: ¥38,000,000、Indirect Cost: ¥11,400,000)
Fiscal Year 2006: ¥8,580,000 (Direct Cost: ¥6,600,000、Indirect Cost: ¥1,980,000)
Fiscal Year 2005: ¥11,700,000 (Direct Cost: ¥9,000,000、Indirect Cost: ¥2,700,000)
Fiscal Year 2004: ¥29,120,000 (Direct Cost: ¥22,400,000、Indirect Cost: ¥6,720,000)
|
Keywords | Aquatron / Horizontal gene transfer / Natural transformation / Conjugation / Transduction / Microcystis aeruginosa bloom / Transposition / Phage / トランスポゾン / 接合性プラスミド / プランクトン群集 / 富栄養化 / 遺伝子伝播頻度 / 遺伝子伝播 |
Research Abstract |
1 Bacterial DNAs which were released from their cells by phage infection are potential resources for gene transfer by natural transformation. Number of bacteria which took a dissolved plasmid with GFP gene in their cells by natural transformation is 100 times as great as that of bacteria which expressed GFP gene. This indicates natural transformation might take place in natural environments with a higher frequency than we have regarded so far. 2 Tetrahymena thermophila, a bacteriovore, inhibited a conjugal transfer from Escherichia coli to Pseudomonas stutzeri by predation on them, and the coexistence of T. thermophila with Microcystis aeruginosa, a producer, enhanced the inhibition. 3 A mini tranposon (mini Tn) was constructed by the transposon Tn MERI1 coding the mercury resistance genes. The mini Tn was introduced into a non-conjugal plasmid. Then this plasmid was transferred into Eshericia coli DH1with conjugal plasmid R338. It was observed the mini Tn transposed into R338 and then the mini Tn on R338 was transferred to Eshericia coli HB101 by conjugation. This suggested the possibility a conjugal transfer through transposition among replicon in a bacterial cell. 4 DNA sequences of the Tn MERI1 type transposon, IR and DR reiterated sequences on mercury resistance bacterial chromosome were analyzed. This analyses revealed that worldwide gene transfer by transposon took place among bacteria. 5 A community dominated with Microcystis aeruginosa, cyanobacteria, in the Aquatron reduced an infectivity of phage EC 10.
|