RSC Advances
·
2017
·Vol. 7
·期 60
·37636-37642
·
IF 3.108
Qiao-Feng Zheng,Mo Yu,Shu-Shen Liu,Fu Chen
Hormesis is a biphasic concentration–response relationship. During the luminescence inhibition test of Vibrio qinghaiensis sp.-Q67 (Q67), some organic solvents display the hormesis phenomenon. However, the mechanism of hormesis with respect to organic solvents remains unclear. This study focuses on luciferase, which is the key factor in luminescent reactions, and explores its role in the mechanism of hormesis. Q67 luciferase has two subunits, α and β. Molecular docking and molecular dynamics simulations were carried out by taking organic solvents as ligand and the two subunits as receptor. In addition, the binding free energies of the complexes formed by the ligand and Q67 luciferase were calculated. The results showed that the organic solvent ligands exhibiting hormesis bind to the β subunit first, while those that do not exhibit hormesis bind more easily to the α subunit. The hormetic organic solvents bind to β subunit first at low concentration, and change the flexibility of residues Ser145–Arg165 located on the α subunit; this enables flavin mononucleotide (FMN) to bind to the α subunit, exhibiting the hormesis phenomenon. With the increasing concentration, redundant molecules start to bind to the α subunit and compete with/block FMN binding to the α subunit, resulting in inhibition.
研究领域:
生物化学
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分子生物学
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环境毒理学
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DOI
高影响因子
PLANT AND SOIL
·
2015
·Vol. 390
·期 1
·337-349
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IF 2.952
Fan Xianwei,Hu Haiyang,Huang Guiyuan,Huang Feiyan,Li Youzhi,Palta Jairo
Background and aims Plant-growth promoting rhizobacteria (PGPR) can promote plant performance under water deficit, but the physiology and biochemistry of the promoting process induced by PGPR under different water deficits is not well known in maize ( Zea mays L). Methods A glasshouse study was conducted to determine the effects of Burkholderia sp. LD-11 on morphophysiological traits for plant growth and homeostasis between reactive oxygen species (ROS) and antioxidant enzymes under five regimens in two maize inbred lines. Results Soil inoculation with Burkholderia sp. LD-11 promoted biomass accumulation and improved instantaneous water-use efficiency (WUEi), regardless of the soil water availability. It also triggered production of indole-3-acetic acid (IAA), decreasing the accumulation of abscisic acid (ABA) induced by the water deficit, alleviated ROS accumulation, and resulted in a reduction in lipid peroxidation induced by the water deficits. Soil inoculation also enhanced the tolerance to water deficit through reducing stomatal aperture by increasing the sensitivity of stomatal conductance ( g
s ) to small changes in ABA concentration in the leaves. Conclusions Soil inoculation with Burkholderia sp. LD-11 enhanced root systems and WUEi, offering a potential avenue for improving maize tolerance to water deficit.
研究领域:
植物生理学
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微生物学
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DOI
高影响因子
CHINESE CHEMICAL LETTERS
·
2016
·
IF 1.947
Dong-Hang Yin,Wei Liu,Zhi-Xiang Wang,Xin Huang,Jing Zhang,De-Chun Huang
The direct three-component aza-Diels–Alder reaction was conducted with lipase as a catalyst for the first time. Under the optimized conditions, the aza-Diels–Alder reaction catalyzed by lipase from Candida sp. 99–125 provided the products in moderate to excellent yields. Meanwhile, the endo / exo ratio reached up to 88:12.
研究领域:
生物化学
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有机合成
·
酶学
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Tong Zhang,Shubin Li,Lei Chen,Weiwen Zhang,Tao Sun
Cyanobacteria are known to be photoautotrophic cell factories capable of converting CO2 into valuable chemicals. The newly discovered marine cyanobacterium Synechococcus sp. PCC 11901 (hereafter PCC 11901) offers several advantages like rapid growth, high biomass, and high salinity tolerance, representing a promising chassis. To promote its application, we developed genetic toolboxes applicable to PCC 11901 in this study. First, a cobalamin (VB12)-independent chassis was constructed, allowing for cheaper cultivation. Second, genome copy numbers and transformation methods were, respectively, measured and optimized. Then, 14 neutral sites were identified and characterized within the genome PCC 11901, providing locations for genetic integration of exogenous cassettes. Subsequently, promoter libraries were developed, reaching an expression range of approximately 800 folds for constitutive promoters and an induction fold of up to approximately 400 for inducible promotors, respectively. As a proof of concept, natural production of the total lipid and phycocyanin was investigated using VB12-independent chassis, which realized an increase of 14.91% with lipid content compared with that of the wild-type strain. Further, we engineered the synthetic pathways of glucosylglycerol (GG) into PCC 11901 using the established toolboxes, reaching 590.41 ± 21.48 mg/L for GG production and self-sedimentation in photoreactors with the highest OD750 nm at 17.57 ± 0.77. Finally, the GG-producing strain grew well in seawater, reaching 324.50 ± 5.34 mg/L in shaking flask, which provided new strategies for cyanobacteria cultivation and production. Our work here made it possible to develop the fast-growing PCC 11901 as efficient carbon-neutral cell factory in the future.
研究领域:
合成生物学
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微生物学
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生物工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Ziqian Wang,Chunyu Du,Ruyu Yan,Shuying Li,Guanyu Zheng,Dahu Ding
Polyhydroxyalkanoates (PHA) are promising candidates for replacing petroleum-derived plastics; however, their high production costs limit their commercialisation. In this study, we successfully isolated an efficient PHA-producing strain from a salt lake, which was subsequently identified as Halomonas sp. WZQ-1. Notably, Halomonas sp. WZQ-1 could serve as a promising cell-factory platform for polyhydroxybutyrate (PHB) production, achieving a comparatively high PHB productivity (7.64 ± 0.4 g L −1 ) under moderate salt stress (60 g L −1 NaCl). We further realised semi-continuous PHB production in a bench-scale fermenter at a steady state by irregularly replenishing the organic substrate. The maximum PHB concentration reached 12.13 g L −1 . Finally, we realised the non-sterile conversion of typical biowastes (e.g. pomelo and cantaloupe residues) to PHB using Halomonas sp. WZQ-1. Encouragingly, 4.36 g L −1 PHB was directly obtained from the hydrolysate of pomelo residues with a characteristic melting temperature of 174.0 °C. Life cycle assessment was employed to systematically evaluate the environmental sustainability and potential challenges of biowaste-driven PHB biorefineries. Overall, our findings could serve as a pivotal step toward the commercialisation of PHB and provide a valuable reference for PHB biorefineries.
研究领域:
微生物学
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环境科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2022
·Vol. 88
·期 6
·
IF 5.005
Ke Huang,Wei Liu,Yuanhe Li,Sha Zeng,Fang-Jie Zhao
Methylarsenate (MAs(V)) is a product of microbial arsenic (As) biomethylation and has also been widely used as an herbicide. Some microbes are able to reduce nontoxic MAs(V) to highly toxic methylarsenite (MAs(III)) possibly as an antibiotic. The mechanism of MAs(V) reduction in microbes has not been elucidated. Here, we found that the bacterium Enterobacter sp. CZ-1 isolated from an As-contaminated paddy soil has a strong ability to reduce MAs(V) to MAs(III). Using a MAs(III)-responsive biosensor to detect MAs(V) reduction in E. coli Trans5α transformants of a genomic library of Enterobacter sp. CZ-1, we identified gshA, encoding a glutamate-cysteine ligase, as a key gene involved in MAs(V) reduction. Heterologous expression of gshA increased the biosynthesis of glutathione (GSH) and MAs(V) reduction in E. coli Trans5α. Deletion of gshA in Enterobacter sp. CZ-1 abolished its ability to synthesize GSH and decreased its MAs(V) reduction ability markedly, which could be restored by supplementation of exogenous GSH. In the presence of MAs(V), Enterobacter sp. CZ-1 was able to inhibit the growth of Bacillus subtilis 168; this ability was lost in the gshA-deleted mutant. In addition, deletion of gshA greatly decreased the reduction of arsenate to arsenite. These results indicate that GSH plays an important role in MAs(V) reduction to generate MAs(III) as an antibiotic.IMPORTANCE Arsenic is a ubiquitous environmental toxin. Some microbes detoxify inorganic arsenic through biomethylation, generating relatively nontoxic pentavalent methylated arsenicals, such as methylarsenate. Methylarsenate has also been widely used as an herbicide. Surprisingly, some microbes reduce methylarsenate to highly toxic methylarsenite possibly to use the latter as an antibiotic. How microbes reduce methylarsenate to methylarsenite is unknown. Here, we show that gshA encoding a glutamate-cysteine ligase in the glutathione biosynthesis pathway is involved in methylarsenate reduction in Enterobacter sp. CZ-1. Our study provides new insights into the crucial role of glutathione in the transformation of a common arsenic compound to a natural antibiotic.
研究领域:
微生物学
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环境科学
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毒理学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Xingxing Peng,Tianyu Li,Qihang Zheng,Yingyuan Lu,Yuzhe He,Yetao Tang,Rongliang Qiu
Hexabromocyclododecane (HBCD) is a typical persistent organic pollutant that is widely detected in the environment. Despite the significant efforts put into its mineralisation , there is still a lack of microorganism resources that can completely mineralise HBCD. Stable isotope analysis revealed that the Citrobacter sp . Y3 can use [ 13 C]HBCD as its sole carbon source and degrade or even mineralise it into 13 CO 2 , with a maximum conversion rate of 100% in approximately 14 days. Strain Y3 could completely mineralise HBCD, which it used as its only carbon source, and six debromination enzymes related to HBCD degradation were found in Y3, including haloalkane dehalogenase (DhaA), haloacid dehalogenase (HAD), etc. A functional gene named HBCD-hd-1 , encoding a HAD, was found to be upregulated during HBCD degradation and heterologously expressed in Escherichia coli . Recombinant E. coli with the HBCD-hd-1 gene transformed the typical intermediate 4-bromobutyric acid to 4-hydroxybutanoic acid and showed excellent degradation performance on HBCD, accompanied by nearly 100% bromine (Br) ion generation. The expression of HBCD-hd-1 in Y3 rapidly accelerated the biodegradation of HBCD. With HBCD as its sole carbon source, strain Y3 could potentially degrade HBCD, especially in a low-nutrient environment.
研究领域:
环境科学
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微生物学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Biotechnology for Biofuels
·
2018
·Vol. 11
·期 1
·1-15
·
IF 5.497
Xu Chunxiao,Sun Tao,Li Shubin,Chen Lei,Zhang Weiwen
Background Cadmium has been a significant threat to environment and human health due to its high toxicity and wide application in fossil-fuel burning and battery industry. Cyanobacteria are one of the most dominant prokaryotes, and the previous studies suggested that they could be valuable in removing Cd2+ from waste water. However, currently, the tolerance to cadmium is very low in cyanobacteria. To further engineer cyanobacteria for the environmental application, it is thus necessary to determine the mechanism that they respond to high concentration of cadmium.Results In this study, a robust strain of Synechocystis PCC 6803 (named ALE-9.0) tolerant to CdSO4 with a concentration up to 9.0 µM was successfully isolated via adaptive laboratory evolution over 802-day continuous passages under cadmium stress. Whole-genome re-sequencing was then performed and nine mutations were identified for the evolved strain compared to the wild-type strain. Among these mutations, a large fragment deletion in slr0454 encoding a cation or drug efflux system protein was found to contribute directly to the resistance to Cd2+ stress. In addition, five other mutations were also demonstrated related to the improved Cd2+ tolerance in ALE-9.0. Moreover, the evolved ALE-9.0 strain was found to obtain cross tolerance to some other heavy metals like zinc and cobalt as well as higher resistance to high light.Conclusion sThe work here identified six genes and their mutations related to Cd2+ tolerance in Synechocystis PCC 6803, and demonstrated the feasibility of adaptive laboratory evolution in tolerance modifications. This work also provided valuable information regarding the cadmium tolerance mechanism in Synechocystis PCC 6803, and useful insights for cyanobacterial robustness and tolerance engineering.
研究领域:
环境科学
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微生物学
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基因组学
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生物技术
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产品关联
DOI
PubMed
高影响因子
Metals
·
2023
·Vol. 13
·期 4
·649
·
IF 2.9
Xiaoxi Ruan,Linlin Yang,Yan Wang,Yizhe Dong,Dake Xu,Mingxing Zhang
The corrosion of carbon steel causes dramatic economic losses each year. Since conventional corrosion prevention approaches may cause pollution problems to the environment, ecofriendly and effective corrosion approaches are desired. Microbiologically influenced corrosion inhibition (MICI) has been reported as a sustainable corrosion prevention method. This work aims to evaluate the corrosion inhibition effect of two bacterial strains,Tenacibaculum mesophilumD-6 andBacillussp. Y-6 by choosing Q235 carbon steel as a model system. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and a series of electrochemical techniques were applied to study the corrosion prevention effect. The electrochemical and pitting results indicated thatT. mesophilumD-6 displayed a better corrosion protection effect.T. mesophilumD-6 formed a denser and thicker biofilm on the Q235 surface thanBacillussp. Y-6. The maximum thickness of theT. mesophilumD-6 biofilms was 11.6 ± 0.7 μm, which is about twice as thick than that ofBacillussp. Y-6. The corrosion prevention mechanism was ascribed to the formation of biofilms as a barrier to block corrosive agents such as O2. This study provides a theoretical foundation for the application of biofilms as green and effective corrosion inhibitors for carbon steel.Keywords:Q235 carbon steel;Tenacibaculum mesophilumD-6;Bacillussp. Y-6;corrosion inhibition;biofilm formation ability
研究领域:
微生物学
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材料科学
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腐蚀工程
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DOI
高影响因子
CHEMBIOCHEM
·
2013
·Vol. 14
·期 12
·1468-1475
·
IF 3.74
Yuhai Jiang,Haoxin Wang,Chunhua Lu,Yanjiao Ding,Yaoyao Li,Yuemao Shen
Graphical A choirmaster is found: An orphan gene cluster containing a chorismatase gene was indentified in Streptomyces sp. LZ35. Characterization showed it to be responsible for the biosynthesis of cuevaene A, a 3-HBA-derived polyketide that shows moderate antibacterial activity against Gram-positive bacteria. Genome sequence analysis of Streptomyces sp. LZ35 has revealed a large number of secondary metabolite pathways, including one encoded in an orphan type I polyketide synthase gene cluster that contains a putative chorismatase/3-hydroxybenzoate synthase gene. Mutagenesis and comparative metabolic profiling led to the identification of cuevaene A as the metabolic product of the gene cluster, thus making it the first 3-HBA containing polyketide biosynthetic gene cluster described to date. Cuv10 was proven to be responsible for the conversion of chorismate into 3-HBA; Cuv18 is speculated to be responsible for the 6-hydroxylation of 3-HBA during polyketide chain elongation. Additionally, several pathway-specific regulatory factors that affect the production of cuevaene A were identified. Our results indicate that targeted inactivation of a gene followed by comparative metabolic profiling is a useful approach to identify and characterize cryptic biosynthetic gene clusters.
研究领域:
微生物学
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分子生物学
·
天然产物化学
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DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2021
·
IF 6.498
Zhuo Jin,Linna Du,Qilu Cheng,Ying Jiang,Cai Hui,Ligen Xu,Yuhua Zhao,Hui Jiang
Microplastics (MPs) and nonylphenol (NP) are typical pollutants that are frequently detected in aquatic environments and can pose a risk to aquatic organisms. However, the responses of algae, the producers in aquatic ecosystems , to MP and NP co-exposure have not been extensively investigated. In this study, polystyrene (PS, 50 mg/L) was selected as a representative MP to evaluate its short-term effects on algae treated with NP (4 mg/L). The results showed that PS mitigated the toxicity of NP to algae after 96 h of exposure, as illustrated by the higher cell densities and pigment concentrations, as well as lower extracellular protein contents and better integrity of intracellular structures, in algae subjected to PS + NP treatment compared with those subjected to NP treatment. Moreover, the upregulated expression of genes involved in photosynthesis and downregulated expression of ribosomal genes as well as genes encoding ATPase and antioxidase, analyzed through RNA-sequencing analysis, further indicated the potential repair and defense mechanisms of PS in NP-treated algae.
研究领域:
环境科学
·
水生生态学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Jia-Yu Lai,Wei-De Zhang,Yu-Xiang Yu
sp hybrid carbon is emerging as a promising unit for covalent modification of organic frameworks and conductive polymers, and has been widely concerned in conjugated polymer catalysts because it can be used to construct π-electron conjugated system. Herein, we provide a simple and effective post reaction strategy to activate g-C 3 N 4 via coupling reactions. The grafted g-C 3 N 4 exhibits improved light absorption and separation of charges, and better water dispersibility along with increased co-catalyst loading sites, which accelerate photocatalytic hydrogen evolution. Photocatalytic H 2 evolution activity of UCN-BTD and UCN-BF, in which terminal amino groups are grafted with 2,1,3-benzothiadiazole,5-(1-propyn-1-yl) or 2,1,3-benzoxadiazole,5-(1-propyn-1-yl), reveals the important role of sp hybrid carbon and electronegativity of the acceptor. The optimized UCN-BTD photocatalyst showed a significant improvement in photocatalytic hydrogen evolution performance (122 μmol·h −1 ), which is nearly five times of that of the pristine g-C 3 N 4 . This work provides insights for the preparation of g-C 3 N 4 -based donor-π-acceptor unit constructed with different conjugated structures.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）