Molecular Anatomy of Polysaccharide-degrading Enzymes from Extremophiles

极端微生物多糖降解酶的分子解剖学

• 批准号: 12650783
• 负责人: NAKAMURA Satoshi
• 金额: $ 2.24万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650783/
• 关键词: Biotechnology; Protein; Glycanase; Extremophile; Xylanase; Alkaliphilic Bacillus sp.; Catalytic domain; Xylan-binding domain; 触媒ドメイン; キシラン結合ドメイン; ファージディスプレイ; 進化分子工学; タンパク質工学; 反応至適pH

Many microorganisms have been discovered at unusual environments such as extreme temperature, pH and salinity. These microorganisms are called "extremophiles" that include thermophiles, psychrophiles, acidophiles, alkaliphiles and halophiles. "Extremozymes" are the enzymes produced by extremophiles and able to function under the extreme conditions. Extremozymes have tremendous potential for industrial applications as well as academic directions. Hemicellulose, originally named for the fraction extracted from plant cell walls with dilute alkali, is one of the most abundant polysaccharide in plant cell walls. Beta-1,4-Xylan is the major component of hemicelluloses ; it accounts for approximately 10 to 30% of the total dry weight of wood. Xylan is a heterogeneous polysaccharide comprising a backbone of beta-1,4- linked xylopyranose units with branches containing acetyl, L-arabino-furanosyl and glucopyranosyl residues. Xylanase (1,4-beta-D-xylan xylanohydrolase ; EC 3.2.1.8) catalyzes the hydrolysis of xylan to xylooligosaccharides and xylose. Alkaliphilic Bacillus sp. strain 41M-1 secretes a xylanase (xylanase J) that has an alkaline pH optimum. Xylanase J is a multidomain enzyme that consists of a family 11/G catalytic domain and a xylan-binding domain. Mutational analyzes revealed some amino acid residues that contribute to catalytic activity, alkaliphily and xylan-binding activity of xylanase J.

在极端温度、pH值和盐度等异常环境中发现了许多微生物。这些微生物被称为“极端微生物”，包括嗜热菌、嗜冷菌、嗜酸菌、嗜碱菌和嗜盐菌。“极端酶”是由极端微生物产生的酶，能够在极端条件下发挥作用。极端酶具有巨大的工业应用潜力以及学术方向。半纤维素是植物细胞壁中含量最丰富的多糖之一，最初因用稀碱从植物细胞壁中提取的组分而得名。β-1，4-木聚糖是半纤维素的主要成分;它占木材总干重的约10%至30%。木聚糖是包含β-1，4-连接的吡喃木糖单元的主链和含有乙酰基、L-阿拉伯呋喃糖基和吡喃葡萄糖基残基的支链的异质多糖。木聚糖酶（1，4-β-D-木聚糖木聚糖水解酶; EC 3.2.1.8）催化木聚糖水解成木寡糖和木糖。嗜碱芽孢杆菌菌株41 M-1分泌具有碱性pH最适值的木聚糖酶（木聚糖酶J）。木聚糖酶J是由家族11/G催化结构域和木聚糖结合结构域组成的多结构域酶。突变分析表明，木聚糖酶J的某些氨基酸残基与其催化活性、嗜碱性和木聚糖结合活性有关。

项目成果

R.Yatsunami et al.: "A Novel Chitosanase from Bacillus sp. Strain K17: Gene Cloning and Expression in Escherichia coil"Nucleic Acids Res.Suppl.. 2. 227-228 (2002)

R.Yatsunami 等：“来自芽孢杆菌菌株 K17 的新型壳聚糖酶：大肠杆菌中的基因克隆和表达”Nucleic Acids Res.Suppl.. 2. 227-228 (2002)

中村 聡: "グリーンバイオケミストリー -ポストゲノム時代を迎え,対話を始めた化学と社会-"現代化学. 2002年4月号. 14-19 (2002)

Satoshi Nakamura：“绿色生物化学——化学与社会已经开始在后基因组时代进行对话”Gendai Kagaku 2002 年 4 月 14-19 号（2002 年）。

T.Dake et al.: "Microbial Degradation of Disodium Terephthalate by Alkaliphilic Dietzia sp.Strain GS-1"Biosci.Biotechnol.Biochem.. 64. 2709-2711 (2000)

T.Dake 等人：“Alkaliphilic Dietzia sp.Strain GS-1 对对苯二甲酸二钠的微生物降解”Biosci.Biotechnol.Biochem.. 64. 2709-2711 (2000)

K. Endo et al.: "Molecular Cloning of a Chitinase Gene from Newly Isolated Alkaliphilic Nocardiopsis sp. Strain F96"Extremophiles. in press.

K. Endo 等人：“从新分离的嗜碱诺卡氏菌 F96 菌株中分子克隆几丁质酶基因”。

T.Matsuo et al.: "Cloning and Expression of Haloarculajaponica Ferredoxin Gene, and Characterization of Recombinant Proteins"Porphyrins. 11. 108-108 (2002)

T.Matsuo 等人：“Haloarculajaponica 铁氧还蛋白基因的克隆和表达，以及重组蛋白的表征”卟啉。