JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
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
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产品关联
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2023
·Vol. 107
·期 5
·1725-1736
·
IF 5
Li Jing,Li Ziyi,Gong Hui,Ma Mengyi,Li Shuolei,Yang Huilin,Zhang Hailin,Liu Jianguo
Abstract In this study, a novel high-activity amylosucrase from Salinispirillum sp. LH10-3-1 (SaAS) was identified and characterized. The recombinant enzyme was determined as a monomer with a molecular mass of 75 kDa. SaAS protein exhibited the maximum total and polymerization activities at pH 9.0 and maximum hydrolysis activity at pH 8.0. The optimum temperature for total, polymerization, and hydrolysis activities were 40, 40, and 45 °C, respectively. Under the optimal pH and temperature, SaAS had a specific activity of 108.2 U/mg. SaAS also showed excellent salt tolerance and could retain 77.4% of its original total activity at 4.0 M NaCl. The addition of Mg 2+ , Ba 2+ , and Ca 2+ enhanced the total activity of SaAS. When the conversion of 0.1 M and 1.0 M sucrose was catalyzed at pH 9.0 and 40 °C for 24 h, the ratios of hydrolysis, polymerization, and isomerization reactions were 11.9:77.4:10.7 and 15.3:53.5:31.2, respectively. The α-arbutin yield of 60.3% was achieved from 20 mM sucrose and 5 mM hydroquinone catalyzed by SaAS. Key points
• A novel amylosucrase from Salinispirillum sp. LH10-3-1 (SaAS) was characterized.
• SaAS has the highest specific enzyme activity among all known amylosucrase.
• SaAS has hydrolysis, polymerization, isomerization, and glucosyltransferase activities.
Graphical Abstract
研究领域:
生物化学
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酶学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Algal Research-Biomass Biofuels and Bioproducts
·
2022
·
IF 5.276
Tiancheng Tang,Benwei Zhu,Zhong Yao
Ulvan , extracted from the marine green algae belonging to the genus Ulva , is a complex water-soluble sulfated polysaccharide which mainly composed of four monosaccharides consisting of rhamnose , xylose , glucuronic acid and iduronic acid . Its complex monosaccharide composition gives ulvan great potential for application in the fields of food, pharmaceuticals, and chemistry. And it can be degraded by ulvan lyases mainly from Polysaccharide Lyases (PL) family of PL24, PL25 and PL28 through β -elimination mechanism, which cleaves the β -glycosidic bond between sulfated rhamnose and glucuronic acid or iduronic acid, thereby producing an Ulva oligosaccharide with unsaturated bond. In this study, we have identified a putative ulvan lyase from Alteromonas sp. TK-45 (2). We heterologously expressed, purified, and biochemically characterized the ulvan lyase, which has removed signal peptide . The results show that ULA-1 had best activity at 45 °C and pH 8.0. The K m and V max values were 13.25 μg·mL −1 and 1.719 μmol·min −1 ·mL −1 , respectively. The thermostability of ULA-1 was excellent, and its activity hardly decreased after incubation at 45 °C for 1 h. ESI-MS analysis showed that the primary end-product were disaccharides to tetrasaccharides . In conclusion, our research has expanded the database of ulvan lyase, and provided the possibility to make full use of ulvan, a huge marine biomass resource .
研究领域:
海洋生物学
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酶学
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生物技术
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生物化学
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产品关联
DOI
高影响因子
Food Bioscience
·
2025
·
IF 5.9
Hongxin Zhang,Junxia Liu,Fred Mwabulili,Peng Li,Xiao Li,Yanli Xie,Yuhui Yang,Qian Li,Weibin Ma,Hang Jia,Yuan Tian
Deoxynivalenol (DON) is a globally significant mycotoxin that can contaminate grains, representing a serious hazard to human and animal health. The current research identified a DON-degrading dehydrogenase from Devosia sp. 63-57 ( Ds DDH). A Ds DDH demonstrated noticeable activation in the presence of Ca 2+ , with electron acceptors including pyrroloquinoline quinone (PQQ), phenazine methosulfate (PMS), and 2,6-dichlorophenolindophenol (DCPIP). The Ds DDH effectively degraded over 82 % of DON (10 μg/mL) within 30 min using PMS or DCPIP as electron acceptors. Additionally, the Ds DDH retained 76 % of its activity after pre-incubating for 2 h at 45 °C. Moreover, the Ds DDH-mediated degradation product of DON was confirmed to be 3-keto-DON, which significantly showed lower toxicity than DON, as verified by zebrafish larvae assays. Furthermore, DON contents in corn and wheat flour decreased from 9.58 to 9.73 to 1.36 and 1.77 μg/g, resulting in degradation rates of 85.85 and 81.76 %, respectively. These findings provide valuable insights into developing a biological detoxification strategy for DON in cereal and feed applications, laying a promising foundation for safer and more effective mycotoxin control.
研究领域:
生物技术
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微生物学
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环境毒理学
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食品安全
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酶学
✓ 已验证
产品关联
DOI
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2025
·Vol. 41
·期 10
·1-12
·
IF 4.2
Sun Ying,Hua Qijing,Cai Yinglin,Dong Yamin,Xiao Yiwen,Bao Jianyin,Zhu Du,Liu Bin,Gao Boliang
Metal ions critically regulate microbial secondary metabolism. This study investigated the regulatory roles of metal ions in Shiraia sp. Slf14, an endophytic fungus with exceptional perylenequinone (PQ) biosynthesis capacity. Among eight ions tested, Na⁺, K⁺, Mg²⁺, and high Ca²⁺ (1.0 g/L) markedly enhanced PQ yields, while Mn²⁺, Cu²⁺, Zn²⁺, and Fe³⁺ (≥ 0.5 g/L) exerted strong inhibition. Na⁺ emerged as the optimal elicitor, boosting production to 504.82 ± 8.62 mg/L (+ 57.96%) at 1.0 g/L without cytotoxicity. Na⁺ exhibited concentration- and time-dependent biphasic regulation. Critical innovation was achieved at 4 g/L Na⁺ added on day 4 (early-log phase), maximizing total PQ yield (1836.95 ± 45.21 mg/L, 5.75 × control), while concentrations > 12 g/L or late addition (≥ day 8) suppressed biosynthesis. Component-specific sensitivities were observed among five PQs. Furthermore, Na⁺ activated the calcineurin pathway: stress-induced Cam/Cna triggered calcineurin-mediated Crz1 nuclear translocation, upregulating key PQ genes ( pksI , omef , hydroxylase ). Concurrent induction of ena1 (Na⁺ exporter) and Ca²⁺-ATPase maintained ion homeostasis. In conclusion, our work pointed out monovalent cations (Na⁺/K⁺) as potent PQ biosynthetic stimulators in filamentous fungi and establish the Na⁺-calcineurin-PQ axis, offering a scalable strategy to overcome production bottlenecks in pharmaceutical PQ manufacturing.
研究领域:
微生物学
·
真菌生物学
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次级代谢产物
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信号转导
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药物生物技术
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分子生理学
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天然产物化学
✓ 已验证
DOI
PubMed
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2017
·Vol. 83
·期 23
·
IF 3.807
Cui-Wei Chu,Bin Liu,Na Li,Shi-Gang Yao,Dan Cheng,Jia-Dong Zhao,Ji-Guo Qiu,Xin Yan,Qin He,Jian He
Thiobencarb is a thiocarbamate herbicide used in rice paddies worldwide. Microbial degradation plays a crucial role in the dissipation of thiobencarb in the environment. However, the physiological and genetic mechanisms underlying thiobencarb degradation remain unknown. In this study, a novel thiobencarb degradation pathway was proposed in Acidovorax sp. strain T1. Thiobencarb was oxidized and cleaved at the C—S bond, generating diethylcarbamothioic S-acid and 4-chlorobenzaldehyde (4CDA). 4CDA was then oxidized to 4-chlorobenzoic acid (4CBA) and hydrolytically dechlorinated to 4-hydroxybenzoic acid (4HBA). The identification of catabolic genes suggested further hydroxylation to protocatechuic acid (PCA) and finally degradation through the protocatechuate 4,5-dioxygenase pathway. A novel two-component monooxygenase system identified in the strain, TmoAB, was responsible for the initial catabolic reaction. TmoA shared 28 to 32% identity with the oxygenase components of pyrimidine monooxygenase from Agrobacterium fabrum, alkanesulfonate monooxygenase from Pseudomonas savastanoi, and dibenzothiophene monooxygenase from Rhodococcus sp. TmoB shared 25 to 37% identity with reported flavin reductases and oxidized NADH but not NADPH. TmoAB is a flavin mononucleotide (FMN)-dependent monooxygenase and catalyzed the C—S bond cleavage of thiobencarb. Introduction of tmoAB into cells of the thiobencarb degradation-deficient mutant T1m restored its ability to degrade and utilize thiobencarb. A dehydrogenase gene, tmoC, was located 7,129 bp downstream of tmoAB, and its transcription was clearly induced by thiobencarb. The purified TmoC catalyzed the dehydrogenation of 4CDA to 4CBA using NAD+ as a cofactor. A gene cluster responsible for the complete 4CBA metabolic pathway was also cloned, and its involvement in thiobencarb degradation was preliminarily verified by transcriptional analysis.IMPORTANCE Microbial degradation is the main factor in thiobencarb dissipation in soil. In previous studies, thiobencarb was degraded initially via N-deethylation, sulfoxidation, hydroxylation, and dechlorination. However, enzymes and genes involved in the microbial degradation of thiobencarb have not been studied. This study revealed a new thiobencarb degradation pathway in Acidovorax sp. strain T1 and identified a novel two-component FMN-dependent monooxygenase system, TmoAB. Under TmoAB-mediated catalysis, thiobencarb was cleaved at the C—S bond, producing diethylcarbamothioic S-acid and 4CDA. Furthermore, the downstream degradation pathway of thiobencarb was proposed. Our study provides the physiological, biochemical, and genetic foundation of thiobencarb degradation in this microorganism.
研究领域:
环境微生物学
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分子生物学
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生物化学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2012
·
IF 4.98
Xiaoyan Wang,Zuoming Zhou,Guohua Jing
Magnetic poly(styrene–glycidyl methacrylate) porous microspheres (MPPM) with high magnetic contents were prepared by surfactant reverse micelles and emulsion polymerization of monomers, in which the well-dispersed Fe 3 O 4 nanoparticles were modified by polyethylene glycol (PEG) and oleic acid (OA) respectively. The characterizations showed that both of the OA–MPPM and the PEG–MPPM were ferromagnetic, however, the OA–MPPM was used to immobilize the bacteria for more advantages. Therefore, the effects of monomer ratio, surfactant, crosslinker and amount of Fe 3 O 4 on the structure, morphology and magnetic contents of the OA–MPPM were investigated. Then, the OA–MPPM was utilized to immobilize Klebsiella sp. FD-3, an iron-reducing bacterium for Fe(III)EDTA reduction applied in NO x removal. Compared with free bacteria, the immobilized FD-3 showed a better tolerance to the unbeneficial pH and temperature conditions.
研究领域:
环境科学
·
微生物学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 27
·18878-18887
·
IF 3.9
Jingnan Jin,Yahui Shi,Baozhong Zhang,Dongjin Wan,Qingye Zhang,Ying Li
Owing to its adverse effects on the environment and human health, benzo[a]pyrene (BaP) has attracted considerable attention and has been used as a model compound in ecotoxicology. In this study, Pannonibacter sp. JPA3 as a BaP-degrading strain was isolated from the production water of an oil well. The strain could remove 80% of BaP at an initial concentration of 100 mg L−1 after 35 d culture. The BaP-4,5-dihydrodiol, BaP-4,5-epoxide, 5-hydroxychrysene, and 2-hydroxy-1-naphthoic acid metabolites were identified in the biodegradation process. Simultaneously, the gene sequence coding for dioxygenase in the strain was amplified and a dioxygenase model was built by homology modeling. Combined with the identification of the metabolites, the interaction mechanism of BaP with dioxygenase was investigated using molecular docking. It was assumed that BaP was initially oxidized at the C4–C5 positions in the active cavity of dioxygenase. Moreover, a hypothesis for the progressive degradation mechanism of BaP by this strain was proposed via the identification of the downstream metabolites. In conclusion, our study provided an efficient BaP degrader and a comprehensive reference for the study of the degradation mechanism in terms of the degrading metabolites and theoretical research at the molecular level.
研究领域:
环境科学
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微生物学
·
生态毒理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2023
·
IF 8.3
Shuai Zhang,Junfeng Su,Shuyu Liu,Yi Ren,Shumiao Cao
There is an urgent demand to investigate mechanisms for the improvement of denitrification in carbon-deficient environment, which will effectively reduce the eutrophication in water bodies polluted by nitrate. In this study, denitrifying bacterium Comamonas sp. YSF15 was used to explore the differences in different carbon source concentrations, with the complete genome, metabolomics, and other detecting methods. Results showed that strain YSF15 was able to achieve efficient denitrification, with complete pathways for denitrification and central carbon metabolism. The carbon deficiency prompted the bacteria to use extracellular amino acid-like metabolites initially, to alleviate inhibition and maintain bioactivity , which also facilitated glycogen storage. The biogenic inhibitors (tautomycin, navitoclax, and glufosinate) at extremely low level potentially favored the competitiveness and intraspecific utilization of extracellular polysaccharides (PS). Optimal solutions for bioaggregation in carbon-deficient condition are achieved by regulating the hydrophobicity , and hydrogen bond in extracellular metabolites. The strategy contributes to the maintenance of bioactivity and adaptation to carbon deficiency. Overall, this study provides a new perspective on understanding the denitrification strategies in carbon-deficient environment, and helps to improve the nitrate removal in low-carbon wastewater treatment .
研究领域:
环境微生物学
·
废水处理
·
代谢组学
·
基因组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2019
·
IF 4.527
Zeyu Wang,Cong Chen,Huan Liu,Dzmitry Hrynshpan,Tatsiana Savitskaya,Jianmeng Chen,Jun Chen
Multi-walled carbon nanotubes (MWCNTs) promote biodegradation in water treatment , but the effect of MWCNT on denitrification under aerobic conditions is still unclear. This investigation focused on the denitrification performance of MWCNT and its toxic effects on Alcaligenes sp. TB which showed that 30 mg/L MWCNTs increased NO 3 - removal efficiency from 84% to 100% and decreased the NO 2 - and N 2 O accumulation rates by 36% and 17.5%, respectively. Nitrite reductase and nitrous oxide reductase activities were further increased by 19.5% and 7.5%, respectively. The mechanism demonstrated that electron generation (NADH yield) and electron transportation system activity increased by 14.5% and 104%, respectively. Cell membrane analysis found that MWCNT caused an increase in polyunsaturated fatty acids, which had positive effects on electron transportation and membrane fluidity at a low concentration of 96 mg/kg but caused membrane lipid peroxidation and impaired membrane integrity at a high concentration of 115 mg/L. These findings confirmed that MWCNT affects the activity of Alcaligenes sp. TB and consequently enhances denitrification performance.
研究领域:
环境科学
·
生物技术
·
水处理
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Lei Zhang,Lingli Zhong,Juying Wang,Yuqiang Zhao,Yiwei Zhang,Yitong Zheng,Weiliang Dong,Xianfeng Ye,Yan Huang,Zhoukun Li,Zhongli Cui
The process of raw starch conversion has attracted extensive attention in recent years due to its high energy conversion efficiency and saving of operational costs. In this study, extensive hydrolysis of raw starch by α-amylase AmyM from Corallococcus sp. EGB was investigated with robust substrate and products tolerance. AmyM showed broad substrate specificity toward raw starches with different types, and kept active and stable over a wide range of temperatures (30–70 °C) and pH values (5.0–9.0) and recycling. The V max values of AmyM towards wheat and corn raw starch were 1111 and 741 μmol/min/mg without depending on Ca 2+ , respectively. SEM analysis showed that AmyM hydrolysis results in the formation of porous and creviced surfaces around the starch granules peripheries. The cost-effective conversion of raw starch for the production of malto-oligosaccharides (MOSs) was identified. AmyM achieved high hydrolysis degree of 90% for 30% wheat and corn raw starch after 20 h at 45 °C with 5 U per mg of raw starch, resulting in formation of 70% MOSs and 30% dextrin. During this process, maltose (G2), maltotriose (G3) and maltotetraose (G4) were produced synchronously with G9 and G11, indicating the potential application in enzymatic conversion of raw starch under low temperature.
研究领域:
生物化学
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酶学
·
食品科学
·
生物技术
✓ 已验证
DOI
高影响因子
Biomass Conversion and Biorefinery
·
2022
·Vol. 13
·期 18
·16807-16818
·
IF 4.05
Wang Qing,Jin Wenbiao,Han Wei,Song Kang,Chen Yidi,Chen Chuan,Jiang Guangming,Zhou Xu
In order to achieve strain improvement and reduction of fermentation medium cost, atmospheric and room temperature plasma (ARTP) mutagenesis and microbial microdroplet culture (MMC) high-throughput screening were used to obtain high-yield Aurantiochytrium sp. strain. Meanwhile, low-cost food waste liquid was added into culture medium to reduce cost. The results showed that the optimal treatment time of ARTP mutagenesis for Aurantiochytrium sp. was 25 s, and 20 mutant strains were screened out by MMC to investigate their performance. The most significant increase in DHA yield was mutant Aurantiochytrium sp. MA20, whose biomass, lipid, and DHA yield were 29.0 ± 0.24, 15.8 ± 0.11, and 9.22 ± 0.37 g/L and 5.77, 16.9, and 83.2% higher than those of original strain, respectively. Compared with the original strain, the DHA proportion in total fatty acids of Aurantiochytrium sp. MA20 increased from 37.2 to 58.3%, while the DHA proportion in biomass increased from 18.4 to 31.7%. The genetic stability for Aurantiochytrium sp. MA20 showed that the yield of biomass, lipid, and DHA of the 50th generation were 29.1 ± 0.13, 16.2 ± 0.31, and 9.47 ± 0.26 g/L, respectively, which was no significant difference between original strain, indicating that the mutant MA20 could be inherited stably. Using food waste liquid to replace 100% yeast extract and 50% sea water of the fermentation medium, the DHA yield reached 9.54 g/L, which was equivalent to that of traditional medium, while the cost of medium was reduced by 45% that achieved the recycle of food waste resource. Graphical abstract
研究领域:
微生物学
·
生物技术
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）