JOURNAL OF MOLECULAR LIQUIDS
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2024
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IF 5.3
Fanjin Meng,Xin Ju,Yuyang Zhou,Lishi Yan,Zhi Chen,Yuqiu Wu,Liangzhi Li
The two major impediments to biomass resourcing are the catalytic efficiency of enzymes and the effectiveness of biomass pretreatment. In this study, six genes encoding β-Glucosidases (BGLs) derived from Paenibacillus sp. LLZ1 were cloned and expressed. The activity of BGL-F, which had the highest enzyme activity, was 24.1 U/mg, which was 39.8–83.7% higher than that of the other BGLs. Molecular docking and surface charge analyses showed that the binding energy of BGL-F to cellobiose and its electronegative ligand-binding pocket were greater than those of other BGLs. On the other hand, by calculating and comparing the Kamlet–Taft (KT) values of deep eutectic solvent (DES) composed of different hydrogen bond donors (HBD) and hydrogen bond acceptors (HDA), it was found that DES composed of betaine and glycerol had the highest α value of 0.97, meaning that it could provide the highest hydrogen bonding capacity, and thus it had the best pretreatment effect on biomass. Analysis by circular dichroism (CD) spectroscopy revealed a decrease in α-helix and an increase in β-strand in the secondary structure of the DES-treated BGL-F, implying an increase in enzyme activity and stability. This result was also confirmed experimentally by the fact that the K m and V max of the enzyme in the DES system increased by 13.2% and 57.9%, respectively, and the inactivation rate (k d ) decreased by 21.4%. The results of this study showed that DES consisting of glycerol-betaine achieved a better balance between the promotion of enzyme activity and biomass 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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可持续化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
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2019
·Vol. 190
·期 3
·826-838
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IF 2.14
Liu Hang,Zhou Min,Ju Xin,Shu Hang,Hu Cuiying,Li Liangzhi
β-Glucosidase (BG) hydrolyzes cellobiose into glucose, and is a vital step in converting ionic liquids (ILs)-pretreated biomass to sustainable biofuels. The inactivation mechanism of BG from Paenibacillus sp. LLZ1 induced by microcrystalline cellulose was explored in various concentrations of ILs, composed of [Emim] + cation and [DEP] − , [OAc] − , [Br] − , [Cl] − , and [BF 4 ] − anions. The FTIR analysis of inactivated BG indicated that the ILs altered its β-sheet content. Moreover, circular dichroism spectroscopy (CD) suggested that the α-helix content decreased, while the β-sheet content increased with the presence of ILs in general. Interestingly, the secondary structure of BG had almost no change after [Emim]DEP treatment, while ionic liquid [Emim]BF 4 treatment caused the irreversible denaturation of BG. Eventually, by adding 0.4 mM of Aerosol OT surfactant, the BG activity was increased by 20.1% in the presence of 25% [Emim]DEP, and the corresponding glucose yield from hydrolysis of cellobiose was increased by 23.9%.
研究领域:
生物化学
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生物技术
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酶学
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可持续能源
✓ 已验证
DOI
PubMed
高影响因子
BIOMASS & BIOENERGY
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2020
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IF 3.551
Wei Yang,Huan Fan,Min Zhou,Zheng Zhou,Lishi Yan,Xin Ju,Liangzhi Li
Stable cellulases are critical for in situ hydrolysis of ionic liquid-pretreated lignocellulose , and surfactants were reported to improve the stability of cellulase in practical circumstances. In this study, synergistic effect of Tween-80 and [Emim]OAc was first identified to enhance the hydrolysis of lignocellulose by Paenibacillus sp. LLZ1 cellulase, proving the effectiveness of surfactants in in situ hydrolysis. Protein fluorescence and near-UV circular dichroism spectroscopy analyses illustrated that ionic liquids might move local residues and alter global tertiary structure of cellulase, leading to higher instability. The addition of Tween-80 might turn the microenvironment of cellulase residues more hydrophilic and reduce the contact of protein with deactivation factors. The synergistic system was further applied in the in situ hydrolysis of microcrystalline cellulose and bagasse cellulose by Paenibacillus cellulase. The enzymatic hydrolysis rate of microcrystalline cellulose was enhanced by 2.5-fold and the final conversion was improved by 45%. Scanning electron microscopy demonstrated the substrate solubilizing effect during reaction by monitoring the morphological changes of lignocellulosic substrates . This study highlighted the potential of applying synergistic reaction system in in situ enzymatic hydrolysis of lignocellulose, and revealed the inherent mechanism initially.
研究领域:
生物化学
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可再生资源与环境科学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Taotao Zhou,Xin Ju,Lishi Yan,Ruiqi Fang,Xinqi Xu,Liangzhi Li
A large quantity of orange peel waste (OPW) is generated per year, yet effective biorefinery methods are lacking. In this study, Trichosporonoides oedocephalis ATCC 16958 was employed for hydrolyzing OPW to produce soluble sugars. Glycosyl hydrolases from Paenibacillus sp. LLZ1 which can hydrolyze cellulose and hemicellulose were mined and characterized, with the highest β-mannanase activity of 39.1 U/mg at pH 6.0 and 50 ℃. The enzyme was overexpressed in T. oedocephalis and the sugar production was enhanced by 16 %. The accumulated sugar contains 57 % value-added mannooligosaccharides by the hydrolysis of mannans. The process was intensified by a pretreatment combining H 2 O 2 submergence and steam explosion to remove potential inhibitors. The mannooligosaccharides yield of 6.5 g/L was achieved in flask conversion and increased to 9.7 g/L in a 5-L fermenter. This study improved the effectiveness of orange peel waste processing, and provided a hydrolysis-based methodology for the utilization of fruit wastes.
研究领域:
生物技术
·
环境科学
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生物化学
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微生物学
✓ 已验证
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）