FEBS Open Bio
·
2020
·Vol. 10
·期 12
·2733-2739
·
IF 2.231
Sai-sai Ding,Jin-peng Zhu,Yang Wang,Bin Wu,Zongpei Zhao
In the paper industry, chlorine is often used to treat the pulp for bleaching. After pulping, a large amount of xylan is present in the fiber. Xylanase can be used to degrade xylan in an eco-friendly process called biobleaching, which can help minimize the usage of chlorine in the delignification process. However, a bottleneck in the adoption of biobleaching is the cost of xylanase and the requirement that xylanase be active and stable at extreme conditions. Here, we investigated whether using sodium alginate beads to immobilize an extracellular xylanase from Bacillus subtilis (Lucky9) can reduce the potential cost of enzyme usage. The optimal pH and the activity of the immobilized enzyme were increased at optimal temperature compared with the free enzyme. In addition, immobilized xylanase was shown to be more stable than free xylanase. The results of this study suggest that the immobilized xylanase has potential applications in the biobleaching industry.
研究领域:
生物技术
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酶工程
·
制浆造纸工业
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DOI
PubMed
高影响因子
BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY
·
2020
·Vol. 84
·期 9
·1788-1798
·
IF 1.516
Liu Feng,Xu Wen-Fei,Mu Hang,Lv Zhi-Rong,Peng Jie,Guo Chao,Zhou Hai-Meng,Ye Zhuo-Ming,Li Xu-Hui
Many phenolic compounds, derived from lignin during the pretreatment of lignocellulosic biomass, could obviously inhibit the activity of cellulolytic and hemicellulolytic enzymes. Acetosyringone (AS) is one of the phenolic compounds produced from lignin degradation. In this study, we investigated the inhibitory effects of AS on xylanase activity through kinetic experiments. The results showed that AS could obviously inhibit the activity of xylanase in a reversible and noncompetitive binding manner (up to 50% activity loss). Inhibitory kinetics and constants of xylanase on AS were conducted by the HCH-1 model (β = 0.0090 ± 0.0009 mM−1). Furthermore, intrinsic and 8-anilino-1-naphthalenesulfonic (ANS)-binding fluorescence results showed that the tertiary structure of AS-mediated xylanase was altered. These findings provide new insights into the role of AS in xylanase activity. Our results also suggest that AS was an inhibitor of xylanase and targeting AS was a potential strategy to increase xylose production.
研究领域:
生物化学
·
酶学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
Biomass Conversion and Biorefinery
·
2024
·
IF 3.5
Yang Shuanghao,Feng Ruirui,Sun Bo,Lu Meizi,Zhao Xingchu,Shen Qirong,Wan Qun
Corncob, as an agricultural waste rich in hemicellulose, plays a crucial role in the effective utilization for biomass conversion and biorefinery. Here, we report a thermophilic GH11 xylanase (Xyn11B) and a β-xylosidase (Xyl43B) in the compost metatranscriptome database, with optimal temperature of 75 ℃ and 70 ℃, respectively, utilized for the synergistic degradation of corncob. Xyn11B consists of a catalytic domain (CD) and a carbohydrate-binding module 60 (CBM60). After deleting CBM60, the T m of the remaining CD Xyn increased by 2.4 ℃ and the half-life at 80 ℃ increased threefold. After 10-h hydrolysis on the NaOH-treated corncob using Xyn11B and CD Xyn , the conversion yield reached 78 and 94 mg sugar/g raw corncob, respectively. Interestingly, in the absence of alkali pretreatment, the conversion yield can reach 107 mg sugar/g raw corncob using 0.1% (mg enzyme/mg corncob) Xyn11B, which is two times higher than that of CD Xyn . Our analysis shows that CBM60 can reduce the non-catalytic adsorption to lignin, which increases the capability of the full-length enzyme to hydrolyze hemicellulose without alkali pretreatment. Furthermore, synergistic hydrolysis with both 0.1% Xyn11B and 0.1% Xyl43B considerably elevates the conversion yield to 296 mg sugar/g raw corncob, which is 2.8-fold higher than that achieved using Xyn11B alone, and comparable to the enzymatic effect observed with the combination of CD Xyn and Xyl43B in alkali pretreatment. Our strategy demonstrates a good example of green hydrolysis of lignocellulosic biomass using enzymes without chemical pretreatment.
研究领域:
生物技术
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生物化学
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酶学
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农业废弃物管理
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可持续化学
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产品关联
DOI
高影响因子
Biomolecules
·
2024
·Vol. 14
·期 9
·1188
·
IF 4.8
Jiao Ma,Zhongke Sun,Zifu Ni,Yanli Qi,Qianhui Sun,Yuansen Hu,Chengwei Li
This study identified a salt-tolerant GH11 xylanase, Xyn st , which was isolated from a soil bacterium Bacillus sp. SC1 and can resist as high as 4 M NaCl. After rational design and high-throughput screening of site-directed mutant libraries, a double mutant W6F/Q7H with a 244% increase in catalytic activity and a 10 °C increment in optimal temperature was obtained. Both Xyn st and W6F/Q7H xylanases were stimulated by high concentrations of salts. In particular, the activity of W6F/Q7H was more than eight times that of Xyn st in the presence of 2 M NaCl at 65 °C. Kinetic parameters indicated they have the highest affinity for beechwood xylan ( K m = 0.30 mg mL −1 for Xyn st and 0.18 mg mL −1 for W6F/Q7H), and W6F/Q7H has very high catalytic efficiency ( K cat / K m = 15483.33 mL mg −1 s −1 ). Molecular dynamic simulation suggested that W6F/Q7H has a more compact overall structure, improved rigidity of the active pocket edge, and a flexible upper-end alpha helix. Hydrolysis of different xylans by W6F/Q7H released more xylooligosaccharides and yielded higher proportions of xylobiose and xylotriose than Xyn st did. The conversion efficiencies of Xyn st and W6F/Q7H on all tested xylans exceeded 20%, suggesting potential applications in the agricultural and food industries.
研究领域:
生物化学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2026
·
IF 8.2
Xuefei Zhu,Aitao Li,Caoxing Huang,Yingjie Du,Qiang Yong
Xylooligosaccharides (XOS) are prebiotic oligosaccharides that can be efficiently produced through enzymatic hydrolysis. Therefore, the oriented control of the degree of polymerization (DP) of oligosaccharides obtained through enzymatic hydrolysis is a crucial research aspect, as oligosaccharides with lower DP exhibit superior biological activity. However, the industrial application of XOS production is limited by the low stability of free xylanase. In this work, mesoporous silica nanoparticles (MSN) were constructed for xylanase immobilization, successfully achieving high yield of XOS with DP of 2 ∼ 6. The recovered activity of Xyl@MSN was 76.85 %, and its residual activity after hydrolysis was 37.7 % higher than that of the free enzyme. Moreover, the conversion rate to xylobiose (X2)- xylohexaose (X6) products reached 66.90 % with Xyl@MSN as catalyst, significantly higher than that of free enzyme (56.03 %). Notably, hydrolysis products using Xyl@MSN as catalyst consisted almost exclusively of X2 and xylotriose (X3). In addition, excellent reusability of Xyl@MSN enables it to retain 41 % of its initial enzymatic activity after being used five reaction cycles with a, high half-life of 462.19 min. Overall, this work not only enables the reuse of the enzyme but also achieves the production of highly active XOS (with nearly 100 % being the X2–X3 fractions), thereby providing new perspectives and technologies for the immobilization of xylanase and the efficient production of XOS.
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DOI
PubMed
高影响因子
Food Chemistry-X
·
2023
·
IF 6.1
Yang Zhao,Luyue Zhang,Shiyu Zhang,Xing Zheng,Mingzhu Zheng,Jingsheng Liu
At presently, the catalytic activity of xylanase is sub-optimal, and the required reaction conditions are harsh. To improve its catalytic activity and stability, xylanase (XY) was chemically modified with maleic anhydride (MA). The enzymatic properties of this maleic anhydride-modified xylanase (MA-XY) were then evaluated and analyzed spectroscopically. The results showed that the thermal stability, use of organic solvents, storage stability and the pH range of 3.0 to 9.0 for MA-XY were better than that for XY alone. The kinetic parameters of the enzyme (K m values) decreased from 40.63 to 30.23 mg/mL. Spectroscopic analysis showed that XY had been modified by the acylation reaction to become a tertiary structure. An assay based on clarifying fruit juices showed that the clarification capacity and reducing sugar content using MA-XY increased compared with those using XY. Overall, this study provides a theoretical basis for improving the application of XY in the food industry.
研究领域:
食品科学
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酶学
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化学修饰
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生物技术
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产品关联
DOI
PubMed
高影响因子
NORDIC PULP & PAPER RESEARCH JOURNAL
·
2021
·Vol. 36
·期 1
·21-32
·
IF 1.04
Guozheng Chen,Jinquan Wan,Yongwen Ma,Yan Wang
The macroscopic and microscopic properties of old newsprint pulp with xylanase, MLac/Glu (modified laccase-glutamate system), and X-MLac/Glu (xylanase synergistic modified laccase-glutamate system) pretreatment was investigated by means of fiber quality measurements (FQA), attenuated total reflectance-infrared spectroscopy (ATR-IR), headspace gas chromatography (HSGC), X-ray diffract ion method (XRD), Low-temperature nitrogen absorption and scanning electron microscopy (SEM). Results showed that, compare with the control pulp, the brightness and lightness (
L
∗
) of hydrogen peroxide bleached pulp after X-MLac/Glu pretreatment increased by 5.86 % ISO and 3.58 %, respectively. FQA analysis revealed that coarseness and fine fiber content increased slightly. The content of carboxyl groups and water retention value increased remarkably by 31.11 % and 39.22 %, respectively. The paper physical analysis showed that the paper strength properties have improved significantly. The crystallinity of cellulose decreased by 3.82 % due to X-MLac/Glu pretreatment. ATR-IR analysis indicated some non-cellulose components are removed. The BJH average pore size and BET specific surface area increased after enzyme pretreatment. The SEM analysis showed that through X-MLac/Glu treatment the fiber surface becomes rough and the connections between the fibers become tighter, more fibrils appeared.
研究领域:
制浆造纸科学
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生物技术
·
材料科学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2017
·
IF 3.154
Xin Liu,Tengfei Liu,Yuebin Zhang,Fengjiao Xin,Shuofu Mi,Boting Wen,Tianyi Gu,Xinyuan Shi,Fengzhong Wang,Lichao Sun
Xylanases (EC 3.2.1.8) are a kind of enzymes degrading xylan to xylooligosaccharides (XOS) and have been widely used in a variety of industrial applications. Among them, xylanases from thermophilic microorganisms have distinct advantages in industries that require high temperature conditions. The CoXynA gene, encoding a glycoside hydrolase (GH) family 10 xylanase, was identified from thermophilic Caldicellulosiruptor owensensis and was overexpressed in Escherichia coli. Recombinant CoXynA showed optimal activity at 90 °C with a half-life of about 1 h at 80 °C and exhibited highest activity at pH 7.0. The activity of CoXynA activity was affected by a variety of cations. CoXynA showed distinct substrate specificities for beechwood xylan and birchwood xylan. The crystal structure of CoXynA was solved and a molecular dynamics simulation of CoXynA was performed. The relatively high thermostability of CoXynA was proposed to be due to the increased overall protein rigidity resulting from the reduced length and fluctuation of Loop 7.
研究领域:
生物化学
·
微生物学
·
结构生物学
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2014
·
IF 5.039
Jingbo Li,Pengfei Zhou,Hongmei Liu,Chunjiang Xiong,Jianghai Lin,Wenjuan Xiao,Yingxue Gong,Zehuan Liu
Sugarcane bagasse (SCB) resulting from different pretreatments was hydrolyzed by enzyme cocktails based on replacement of cellulase (Celluclast 1.5 L:Novozym 188 = 1 FPU:4 pNPGU) by xylanase or pectinase at different proportions. Lignin content of NaOH pretreated SCB and hemicellulose content of H 2 SO 4 pretreated SCB were the lowest. NaOH pretreatment showed the best for monosaccharide production among the four pretreatments. Synergism was apparently observed between cellulase and xylanase for monosaccharide production from steam exploded SCB (SESB), NaOH, and H 2 O 2 pretreated SCB. No synergism was observed between cellulase and pectinase for producing glucose. Additionally, no synergism was present when H 2 SO 4 pretreated SCB was used. Replacement of 20% of the cellulase by xylanase enhanced the glucose yield by 6.6%, 8.8%, and 9.5% from SESB, NaOH, and H 2 O 2 pretreated SCB, respectively. Degree of synergism between cellulase and xylanase had positive relationship with xylan content and was affected by hydrolysis time.
研究领域:
生物化学
·
可再生能源
·
酶工程
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Xu Li,Lei Zhang,Zhitong Jiang,Lin Liu,Jihong Wang,Lingli Zhong,Tao Yang,Qin Zhou,Weiliang Dong,Jie Zhou,Xianfeng Ye,Zhoukun Li,Yan Huang,Zhongli Cui
Although xylanase have a wide range of applications, cold-active xylanases have received less attention. In this study, a novel glycoside hydrolase family 8 (GH8) xylanase from Sorangium cellulosum with high activity at low temperatures was identified. The recombinant xylanase (XynSc8) was most active at 50 °C, demonstrating 20% of its maximum activity and strict substrate specificity towards beechwood and corncob xylan at 4 °C with V max values of 968.65 and 1521.13 μmol/mg/min, respectively. Mesophilic XynSc8 was active at a broad range of pH and hydrolyzed beechwood and corncob xylan into xylooligosaccharides (XOS) with degree of polymerization greater than 3. Moreover, incorporation of XynSc8 (0.05–0.2 mg/kg flour) provided remarkable improvement (28–30%) in bread specific volume and textural characteristics of bread compared to commercial xylanase. This is the first report on a novel cold-adapted GH8 xylanase from myxobacteria, suggesting that XynSc8 may be a promising candidate suitable for bread making.
研究领域:
生物化学
·
食品科学
·
微生物学
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DOI
PubMed
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Zhenyu Wang,Xingyuan Cao,Nan Li,Zhengjiao Yang,Ming Lei,Yang Zhao,Lizhi Wang,Zhenyu Li,Dong Liu,Huanqing Niu,Hanjie Ying
Butanol is an attractive second-generation biofuel as well as an important chemical. Production of butanol from lignocellulosic feedstock via consolidated bioprocessing has attracted increasing interest in recent years. However, this has been limited by the inefficient degradation of extracellular polysaccharides in butanol-producing strains. In this study, production of butanol directly from hemicellulose was achieved simply through overexpression of an indigenous xylanase in Clostridium acetobutylicum. The xylanase (XynB) encoded by CA_P0053 was highly soluble and fully secreted from C. acetobutylicum. The extracellular xylanase activity was increased 88-fold, and 4.03 g/L biobutanol was obtained from hemicellulose, which has been the highest yield yet reported from either hemicellulose or xylan. This study proved that the solventogenic C. acetobutylicum had great potential for consolidated production of biofuels. Understanding and applying its secretion mechanism will be of great significance in the future.
研究领域:
生物工程
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微生物学
·
生物技术
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2015
·
IF 2.912
Xiongliang Huang,Zhe Li,Chenyu Du,Jufang Wang,Shuang Li
A xylanase gene was cloned and characterized from Thermoanerobacterium aotearoense SCUT27, which was attested to consist of a signal peptide, one glycoside hydrolase family 10 domain, four carbohydrate binding modules, and three surface layer homology domains. The change of expression host from Escherichia coli to Bacillus subtilis resulted in a 4.1-fold increase of specific activity for the truncated XynAΔSLH. Five different versions of secretion signals in B. subtilis indicated that it was preferably routed via a Sec-dependent pathway. Purified XynAΔSLH showed a high activity of 379.8 U/mg on beechwood xylan. XynAΔSLH was optimally active at 80 °C, pH 6.5. Thin layer chromatography results showed that xylobiose and the presumed methylglucuronoxylotriose (MeGlcAXyl3) were the main products liberated from beechwood xylan catalyzed by the recombinant xylanase. All of the results suggest that XynAΔSLH is a suitable candidate for generating xylooligosaccharides from cellulosic materials for industrial uses.
研究领域:
生物技术
·
酶学
·
微生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）