Isolation and Characterization of a Polycyclic Aromatic hydrocarbons-degrading Enzyme from Xylaria regalis

炭角菌分解多環芳香族化合物酵素之分離及其生化特性之探討

張勝祺(Shenq-Chyi Chang) ； 陳明凱(Ming-Kai Chen) ； 魏玎玲(Ding-Ling Wei) ； 鄭閔魁(Min-Kuei Cheng)

《Fungal Science》 22卷1&2期 (2007/06) Pp. 25-33

https://doi.org/10.7099/FS.200706.0025

摘要

從21株真菌篩選分解多環芳香族化合物Pyr及BaP之能力，發現炭角菌(Xylaria regalis)分解能力最強。進一步從其菌絲分離及純化此酵素，經由離子交換樹脂管柱、疏水性管柱及分子篩膠體管柱之純化，得到最終產物活性提高70.5倍，回收率45%，專一活性4690U/mg；經由SDS-膠體電泳分析得知此酵素分子量為29KDa。此酵素最適反應Ph值8.5，最適反應溫度30℃，且在高溫相當穩定，在100℃反應8小時仍保持60%之活性。

關鍵字

炭角菌 ； 多環芳香族化合物 ； 多環芳香族化合物分解酵素

並列摘要

Twenty-one fungal species were screened for capability of removing pyrene and benzo (a) pyrene in culture. Xylaria regalis was found to show the highest activity. An PAHs-degrading enzyme was purified to homogeneity from the culture mycelium of X. regalis. The crude enzyme was subjected to a series of purification procedures, including QAE Sephadex A-25 anion exchange column, hydrophobic interaction phenyl 650M column and Fractogel HW-55 column chromatography, respectively. The enzyme was purified 70.5 fold, giving a 45% yield. The specific activity was 4690U/mg. The molecular mass of the purified PAHsdegrading enzyme estimated by SDS-PAGE was approximately 29kDa. The optimal pH of the purified enzyme was 8.5 and the enzyme was stable between pH 8.0-9.0. The optimal temperature of the enzyme was 30℃ and it's activity was still stable at higher temperatures. The enzyme was found stable within 2h at 100℃ and retained 60% of activity after 8 h incubation.

並列關鍵字

polycyclic aromatic hydrocarbons PAHs ； PAHs-degrading enzyme ； Xylaria regalis