ヒルタ オサム   Osamu HIRUTA
  蛭田 修
   所属   熊本保健科学大学  品質保証・精度管理学共同研究講座
   熊本保健科学大学大学院  保健科学研究科 保健科学専攻
   職位   特命教授
言語種別 英語
発行・発表の年月 1998
形態種別 研究論文 
査読 査読あり
標題 Enzymatic degradation of poly(hydroxyalkanoate) by Corynebacterium aquaticum IM-1 isolated from activated sludge
執筆形態 共著
掲載誌名 Polymer Degradation and Stability
掲載区分国外
巻・号・頁 61(2)
著者・共著者 Masako Ito, Yuji Saito, Toshio Matsunobu, Osamu Hiruta, Hidehi Takebe
概要 Poly(4-hydroxybutyric acid)-degrading bacteria were isolated from activated sludge. One strain was selected, which was identified as Corynebacterium aquaticum. The strain C. aquaticum IM-1 excreted an extracellular poly(hydroxyalkanoate) [PHA]depolymerase and grew on 4-hydroxybutyric acid as the sole carbon source. The molecular weight of the purified PHA depolymerase was determined as approximately 33000 Da by SDS-PAGE. The optimum activity of the depolymerase was observed at pH 6.5 and 40 °C. and N-terminal sequences of the depolymerase were not applicable to the well-known enzymes. The enzymatic degradation of polyesters was studied by the erosion rate of solution-cast films of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and poly(ω-hydroxyalkanoate) of different chain lengths (C3–C6). The water-soluble products of poly(3-hydroxybutyrateco-97mol%4-hydroxybutyrate) film were revealed by 1H NMR and FAB-MS analysis, and the main product was the dimer of 4-hydroxybutyric acid.