| Co-Investigator(Kenkyū-buntansha) |
ODA Kohei Kyoto Institute of Technology, Department of Applied Biology, Professor, 繊維学部, 教授 (50081584)
MIYAMOTO Masatoshi Kyoto Institute of Technology, Faculty of Textile Science, Associate Professor, 繊維学部, 助教授 (70149524)
|
|---|
| Budget Amount *help |
¥13,800,000 (Direct Cost: ¥13,800,000)
Fiscal Year 2000: ¥5,800,000 (Direct Cost: ¥5,800,000)
Fiscal Year 1999: ¥8,000,000 (Direct Cost: ¥8,000,000)
|
|---|
| Research Abstract |
The results in this research are as follows.
1.Screening, isolation, and identification of PET-decomposing microorganisms : We have succeeded in getting six strains, which could decompose the non-crystalline PET fibers. Some of them were identified as Trichosporon sp.No.85, Sphingomonas paucimobilis No.77-2, and Arthrobacter sp.No.97-2, respectively.
2.Purification of PET-decomposing enzyme from Arthrobacter sp.No, 97-2 : A 35-kDa protein was purified as a candidate for PET-decomposing enzymes from the culture filtrate of Arthrobacter sp.No.97-2. The amino-terminal sequence of the purified enzyme showed high similarity with that of flagellin (identity ; 63% and similarity ; 75%). We could not elucidate enzymatic properties, because of low specific activity.
3.Development of new assay methods : Observations of the surface of PET fiber by a scanning electron microscopy and measurements of tensile strength of PET fiber have been used for assay of PET-decomposing activities. However, these assay methods take a lot of time, and also their data are not accurate. To improve assay methods for PET-decomposing enzymes, measurements of viscosity, gel permeation chromatography, and NMR spectroscopy were introduced. Four kinds of substrates were used : PET fiber, PET film, PET oligomer, and OEST (oligo (ethylene succinate-co-terephthalate). These assay methods turned out to be useful for assay of PET-decomposing activities.
Some of our researches were not carried. The reasons are (1) it was very difficult to keep such PET-decomposing strains with high activities. These enzymes might be coded on plasmids. (2) There were no any adequate assay methods, which are reliable.
|
