Novel Synthesis of Lactosyl .BETA.-Glycosides and Analogs through Cellulase-mediated Transglycosylation or Condensation Reaction
スポンサーリンク
概要
- 論文の詳細を見る
Alkyl β-lactosides were directly synthesized by β-lactosyl transfer reaction from p-nitrophenyl β-lactoside (Lacβ-pNP) to various 1-alkanols (n=2-12), utilizing a commercially available cellulase preparation of Trichoderma reesei C1. When 1-octanol and dodecanol were acceptors, octyl β-lactoside and dodecyl β-lactoside were obtained as transfer products, respectively. Furthermore, the enzyme catalyzed N-acetyllactosaminyl transfer reaction from p-nitrophenyl β-N-acetyllactosaminide (LacNAcβ-pNP) not only to 1-alkanol, but also to the OH-4 position of Man and Glc to produce the trisaccharides. As an alternative method, alkyl β-lactosides were synthesized by condensation reaction of lactose with alkanols. When various 1-alkanols (n: 2-8) were used, the corresponding alkyl β-lactosides were obtained in the yields of 1-4% based on lactose added. Further, condensation reaction between lactose and glycerol was effectively catalyzed to produce 1-O-β-lactosyl-(R,S)-glycerols and 2-O-β-lactosyl glycerol in a molar ratio of 7:3 and in a 20% yield based on lactose added. The enzyme also catalyzed the condensation with 2-propanol and allyl alcohol. In a similar manner, when LacNAc was used as a glycon substrate, the enzyme catalyzed the condensation with various alkanols and glycerol. The yields were lower than those obtained from reactions with lactose. Finally, purification of an enzyme possessing condensation activity was carried out by chromatographies using DEAE-Sepharose and Mono P columns, in order to reveal whether the same enzyme molecule would catalyze in both the lactosyl- and N-acetyllactosaminyl-condensing reactions. It was specified that a single enzyme works both condensation reactions, based on the substrate competition assay on hydrolysis.
- 日本応用糖質科学会の論文
日本応用糖質科学会 | 論文
- 古細菌の産生する新規な糖質関連酵素およびそれらを用いたトレハロースの生産
- PCR法による米 (Oryza sativa L.) の品種判別およびその米加工品への応用
- モチ米のアミロペクチン鎖長分布と米粒の物理特性との関係
- ジャポニカ米とインデカ米の澱粉とプロテインボディの結合脂質について
- 促通拡散型糖輸送担体分子の構造機能相関