6KJL

Xylanase J from Bacillus sp. strain 41M-1

6KJL の概要

• エントリーDOI: 10.2210/pdb6kjl/pdb
• 分子名称: Endo-1,4-beta-xylanase, CALCIUM ION, 4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID, ... (6 entities in total)
• 機能のキーワード: gh11, xylanase, enzyme, hydrolase
• 由来する生物種: Bacillus sp. 41M-1
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 74633.59

構造登録者

Manami, S.,Teisuke, T.,Nakatani, K.,Katano, K.,Kojima, K.,Saka, N.,Mikami, B.,Yatsunami, R.,Nakamura, S.,Yasukawa, K. (登録日: 2019-07-22, 公開日: 2019-09-04, 最終更新日: 2023-11-22)

主引用文献

Takita, T.,Nakatani, K.,Katano, Y.,Suzuki, M.,Kojima, K.,Saka, N.,Mikami, B.,Yatsunami, R.,Nakamura, S.,Yasukawa, K.
Increase in the thermostability of GH11 xylanase XynJ from Bacillus sp. strain 41M-1 using site saturation mutagenesis.
Enzyme.Microb.Technol., 130:109363-109363, 2019

PubMed Abstract: GH11 xylanase XynJ from Bacillus sp. strain 41M-1 has a β-jellyroll fold composed of eight β strands with a deep active-site cleft. We hypothesized that the thermostability of XynJ will increase if the flexibility of the β strands in the jellyroll structure is decreased without impairing activity. To verify this hypothesis, we introduced random mutations into Tyr13-Arg104 and Gly169-Tyr194, both of which are located in the β-jellyroll fold of XynJ, to construct a site saturation mutagenesis library. By screening 576 clones followed by site saturation mutation analysis of Thr82, T82A was selected as the most thermostable variant. In the hydrolysis of beechwood xylan at pH 7.8, the temperatures required to reduce initial activity by 50% in 15 min were 61 °C for the wild-type XynJ (WT) and 65 °C for T82A. The optimum hydrolysis temperatures were 60 °C for WT and 65 °C for T82A. There was little difference in the k and K values and the pH dependence of activity between WT and T82A. Crystallographic analysis of WT and T82A revealed that thermostabilization by the T82A mutation might result from the removal of unfavorable van der Waals interactions. Thus, a highly thermostable XynJ variant was generated without impairing activity using this mutation strategy.

PubMed: 31421720
DOI: 10.1016/j.enzmictec.2019.109363

実験手法

X-RAY DIFFRACTION (2.45 Å)