成果報告書詳細
管理番号20110000000592
タイトル*平成22年度中間年報 新エネルギー技術研究開発 バイオマスエネルギー等高効率転換技術開発(先導技術開発) 細菌のリグニン分解酵素遺伝子による植物細胞壁改変技術の開発
公開日2011/6/7
報告書年度2010 - 2010
委託先名国立大学法人東京農工大学共生科学技術研究院 学校法人加計学園岡山理科大学 独立行政法人森林総合研究所 国立大学法人長岡技術科学大学
プロジェクト番号P07015
部署名新エネルギー部
和文要約和文要約等以下本編抜粋:1.研究開発の内容及び成果等 1.1 リグニン二量体の化学合成 前年度に引き続き、課題遂行に必要な各種リグニン二量体(モノリグノール二量体)の化学合成を定期的に行い、遺伝子のクローニングおよび遺伝子組換え体の評価に供した。3種の代表的なリグニン二量体(モノリグノール二量体)である8-8'型二量体(ピノレジノール)、8-5'型二量体(フェニルクマラン)、および8-O-4'型二量体(グアイアシルグリセロールーβーコニフェリルエーテル)については、バニリンより数工程で合成したモノリグノール(コニフェリルアルコール)の酸化的カップリングにより合成した。
英文要約Title: Development of Technology for High-efficiency Conversion of Biomass and other Energy/ Genetic engineering of plant cell wall by application of bacterial genes for lignin-degrading enzymes (FY2010-FY2011) FY2010 Annual Report: In order to contribute to efficient and sustainable production of bioethanol from lignocellulosic biomass, we try to generate transgenic trees whose biomass can be easy to convert into soluble and fermentable sugars by enzymatic hydrolysis. To this end, we used different types of bacterial genes isolated from, Shingobium sp. strain SYK-6 (hereafter refer to as SYK-6), which is able to catabolize a wide variety of phenolic compounds by its unique enzymatic system. In last year, we generated different types of transgenic Arabidopsis plants with eight transgene constructs prepared from the well-characterized SYK-6 genes under the control of cauliflower mosaic virus 35S promoter. In this year, among the generated transgenic plants, we concentrated on analysis of transgenic Arabidopsis transformed with the ligD gene. This bacterial gene encodes a polypeptide, which belongs to the short-chain dehydrogenase/reductase and catalyzes the oxidation step of benzyl positions of aryl-glycerol-beta-aryl ether structures. Partial oxidation at benzyl positions of 8-O-4’ units of lignin can be expected by overexpression of the ligD gene in the plants. The structural conversion of lignin may accelerate the degradation of lignin under alkaline condition and subsequent enzymatic saccharification of lignocellulose containing the transgenic plants. At first we confirmed the expression of ligD transgene in the plants by Western blot analysis with antiserum against LigD polypeptide. Positive expressions of the ligD were detected in some of the transgenic plants analyzed. Enzymatic activities of LigD in crude extracts prepared from both cytosolic and apoplastic fractions of the plants were also detected. As expected, 2D NMR analysis suggests that the abundance of the alpha-keto structure in 8-O-4’ units of lignin in the transgenic plants relatively higher than that in the wild-type plant. Further analysis of the lignin structure and efficiency of enzymatic saccharification of the transgenic lignocelluloses should be done in next year. In addition to the generation of the transgenic plants described above, a novel gene for conversion of pinoresinol has been successfully isolated in this year. This gene, pinZ, encodes a polypeptide of 316 amino acids, whose deduced molecular mass is approximately 34 kDa. PinZ shares 21% amino acid identity with pinoresinol reductase (AtPrR1) isolated from Arabidopsis. Recombinant His-tagged PinZ catalyzes the conversion of pinoresinol to lariciresinol and then to secoisolariciresinol. Catalytic activity for the first step (pinoresinol to lariciresinol) is quite higher than that of AtPrR1. Generation of transgenic plants with pinZ is now in progress.
ダウンロード成果報告書データベース(ユーザ登録必須)から、ダウンロードしてください。

▲トップに戻る