ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2017
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IF 3.743
Xiong Pan,Saige Wang,Nan Shi,Hua Fang,Yunlong Yu
The application of the herbicide chlorimuron-ethyl has a lasting toxic effect on some succession crops. Here, a bacterium capable of utilizing chlorimuron-ethyl as the sole source of nitrogen was isolated from the contaminated soil and was identified as Enterobacter ludwigii sp. CE-1, and its detoxification and degradation of the herbicide were then examined. The biodegradation of chlorimuron-ethyl by the isolate CE-1 was significantly accelerated with increasing concentration (1–10 mg/l) and temperature (20–40 °C). The optimal pH for the degradation of chlorimuron-ethyl by the isolate CE-1 was pH 7.0. A pathway for the biodegradation of chlorimuron-ethyl by the isolate CE-1 was proposed, in which it could be first converted into 2-amino-4-chloro-6-methoxypyrimidine and an intermediate product by the cleavage of the sulfonylurea bridge and then transformed into saccharin via hydrolysis and amidation. The plant height and fresh weight of corn that had been incubated in nutrient solution containing 0.2 mg/l of chlorimuron-ethyl significantly recovered to 83.9% and 83.1% compared with those in the uninoculated control, although the root growth inhibition of chlorimuron-ethyl could not be alleviated after inoculation for 14 d. The results indicate that the isolate CE-1 is a promising bacterial resource for the biodegradation and detoxification of chlorimuron-ethyl.
研究领域:
环境科学
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微生物学
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植物生理学
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产品关联
DOI
PubMed
高影响因子
Microorganisms
·
2022
·Vol. 10
·期 3
·575
·
IF 4.926
Ge Gao,Yan Zhang,Shaofang Niu,Yu Chen,Shaojing Wang,Nusratgul Anwar,Shuai Chen,Guoqiang Li,Ting Ma
Precise classification of bacteria facilitates prediction of their ecological niche. The genusEnterobacterincludes pathogens of plants and animals but also beneficial bacteria that may require reclassification. Here, we propose reclassification ofEnterobacterFY-07 (FY-07), a strain that has many plant-growth-promoting traits and produces bacterial cellulose (BC), to theKosakoniagenera. To re-examine the taxonomic position of FY-07, a polyphasic approach including 16S rRNA gene sequence analysis, ATP synthase β subunit (atpD) gene sequence analysis, DNA gyrase (gyrB) gene sequence analysis, initiation translation factor 2 (infB) gene sequence analysis, RNA polymerase β subunit (rpoB) gene sequence analysis, determination of DNA G + C content, average nucleotide identity based on BLAST, in silico DNA–DNA hybridization and analysis of phenotypic features was applied. This polyphasic analysis suggested thatEnterobactersp. FY-07 should be reclassified asKosakonia oryzendophyticaFY-07. In addition, the potential of FY-07 to promote plant growth was also investigated by detecting related traits and the colonization of FY-07 in rice roots.Keywords:Enterobacter;Kosakonia;reclassification;FY-07;promote plant growth
研究领域:
微生物学
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植物科学
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2016
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IF 4.917
Richen Lin,Jun Cheng,Lingkan Ding,Wenlu Song,Min Liu,Junhu Zhou,Kefa Cen
Ferric oxide nanoparticles (FONPs) were used to facilitate dark hydrogen fermentation using Enterobacter aerogenes . The hydrogen yield of glucose increased from 164.5 ± 2.29 to 192.4 ± 1.14 mL/g when FONPs concentration increased from 0 to 200 mg/L. SEM images of E. aerogenes demonstrated the existence of bacterial nanowire among cells, suggesting FONPs served as electron conduits to enhance electron transfer. TEM showed cellular internalization of FONPs, indicating hydrogenase synthesis and activity was potentially promoted due to the released iron element. When further increasing FONPs concentration to 400 mg/L, the hydrogen yield of glucose decreased to 147.2 ± 2.54 mL/g. Soluble metabolic products revealed FONPs enhanced acetate pathway of hydrogen production, but weakened ethanol pathway. This shift of metabolic pathways allowed more nicotinamide adenine dinucleotide for reducing proton to hydrogen.
研究领域:
微生物学
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生物技术
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环境科学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
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2021
·Vol. 11
·期 50
·31601-31607
·
IF 3.361
Bi-Xian Zhang,Pei-Shan Li,Ying-Ying Wang,Jia-Jun Wang,Xiu-Lin Liu,Xue-Yang Wang,Xiao-Mei Hu
Indole-3-acetic acid (IAA) plays an important role in the growth and development of plants. In this study, a series of predominant strains were isolated and identified as Enterobacter sp. with remarkable IAA-producing capabilities. The IAA-producing strains are mainly tryptophan-dependent and have significantly high yields of IAA (3477 μg mL−1 and 3378 μg mL−1). The ipdC gene encoding indole-3-pyruvate decarboxylase was identified by genomic analysis and RT-qPCR analysis, indicating the involvement of the indole-3-pyruvic acid (IPyA) pathway of IAA biosynthesis. The IPyA pathway was also confirmed by the intermediate assay. The IAA product of microbial metabolites was isolated, purified and characterized. These microbes exhibiting IAA production significantly promoted the growth of maize, increasing root length, plant height, fresh weight and dry weight. Thus, Enterobacter sp. with high IAA production has great prospects in agricultural and industrial applications.
研究领域:
微生物学
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植物学
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农业科学
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DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
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2024
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IF 3.1
Qiao Xi,Jiang Mengna,Zhu Enze,Gu Yiwen,Chen Zhuoran,Ju Xin,Li Liangzhi,Zhong Xia,Chen Zhi
Chitin, a natural organic compound with content slightly lower than cellulose, is also known for chitosan, a substance derived from chitin through deacetylation. In this experiment, preliminary screening was conducted using the plate discoloration circle method, leading to the selection of a high-yield CDA-producing strain from 28 candidates through rescreening. Morphological characteristics and 16S rDNA sequence analysis revealed 99.93% homology with Enterobacter sichuanensis strain N24, thus naming this strain Enterobacter strain ZCDA27. Initial fermentation of the strain yielded CDA activity of 9.29 U/mL. Single-factor optimization was then performed, followed by a PB test to screen for significant factors affecting enzyme production. The response surface method was used to further optimize the fermentation conditions. The optimal fermentation conditions for the carbon source, nitrogen source, metal ion, fermentation temperature, time, liquid volume, and initial pH were explored. Significant factors affecting enzyme production, including MgSO 4 , initial medium pH, and fructose levels, were identified using the PB test. Finally, the fermentation conditions of ZCDA27 were optimized using the Box-Behnken design combined with RSM, which comprised fructose at 1.020%, magnesium sulfate at 0.016%, and peptone at 1%. The fermentation conditions included a temperature of 37, initial pH of 7.1, rotation speed of 140 × g , fermentation time of 28 h, inoculation amount of 2%, and liquid volume of 40%. Under these conditions, the enzyme activity of ZCDA27 reached 14.52 U/mL, a 1.6-fold increase from the pre-optimization levels. In summary, this study provides an experimental foundation for further development and application of Enterobacter spp. ZCDA27 CDA.
研究领域:
微生物学
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生物化学
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酶工程
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产品关联
DOI
PubMed
高影响因子
Energies
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2021
·Vol. 14
·期 11
·2990
·
IF 3.004
Qing Zhang,Jing Zhang,Shuai Zhao,Peizhi Song,Yanli Chen,Pu Liu,Chunlan Mao,Xiangkai Li
Lignin-feeding insect gut is a natural ligninolytic microbial bank for the sustainable conversion of crop straw to biogas. However, limited studies have been done on highly efficient microbes. Here, an efficient ligninolytic strainEnterobacter hormaecheiKA3 was isolated from the gut microbiomes of lignin-feedingHypomeces squamosusFabricius, and its effects on lignin degradation and anaerobic digestion were investigated. No research has been reported. Results showed that strain KA3 had better lignin-degrading ability for corn straw with a higher lignin-degrading rate (32.05%) and lignin peroxidase activity (585.2 U/L). Furthermore, the highest cumulative biogas yield (59.19 L/kg-VS) and methane yield (14.76 L/kg-VS) were obtained for KA3 inoculation, which increased by 20% and 31%, respectively, compared to CK. Higher removal rates of COD, TS, and vs. of 41.6%, 43.11%, and 66.59% were also found. Moreover, microbial community diversity increased as digestion time prolonged in TG, and bacteria were more diverse than archaea. The dominant genus taxon, for methanogens, wasMethanosatein TG, while in CK wasMethanosarcina. For bacteria, dominant taxa were similar for all groups, which wereSolibacillusandClostridium. Therefore, strain KA3 improved the methane conversion of the substrate. This study could provide a new microbial resource and practical application base for lignin degradation.Keywords:microbial lignin degradation;gut microbiome;Enterobacter hormaecheiKA3;biogas production;microbial community
研究领域:
微生物学
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环境科学
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生物能源
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DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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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 Environmental Chemical Engineering
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2025
·
IF 7.2
Teng-Fei Ma,Hong-Xi Ma,Chong-Yang Xing,Hui-Min Fu,Yu Shen,You-Peng Chen,Xiang-Yang Wei
This study combines physiological and proteomic analyses to explore the silver nanoparticles (Ag NPs) induced stress response and resistance mechanisms in the aerobic denitrifying Enterobacter cloacae strain HNR (strain HNR). Results demonstrated concentration-dependent inhibition: at 0.30 mM Ag NPs, bacterial growth (OD 600 ) decreased to 79.7 % of the control, while nitrate removal efficiency dropped to 52.4 %, accompanied by a 6.4-fold increase in nitrite accumulation. Activities of nitrate reductase and nitrite reductase were reduced to 34.3 % and 41.6 %, respectively. Ag NPs also compromised motility, induced oxidative stress (33.11 % rise in intracellular reactive oxygen species), and disrupted membrane integrity (10.4 % lactate dehydrogenase release). Conversely, extracellular polymeric substances (EPS) production surged by 25.6 % under low Ag NPs (0.01 mM), primarily driven by polysaccharide synthesis (55.5 % increase). Proteomics revealed 1987 differentially expressed proteins (978 upregulated, 1009 downregulated). Downregulated pathways (DNA repair, ribosome biosynthesis, glycerophospholipid metabolism, ABC transporters, oxidative phosphorylation, etc.) indicated that Ag NPs disrupted bacterial genome stability, inhibit synthesis of protein, cell membrane, and interfered with material transport and energy production. In response, strain HNR upregulated the sulfur relay system, tyrosine metabolism, and pentose and glucuronate interconversions to combat oxidative stress and energy metabolism inhibition. Additionally, strain HNR increased EPS production and cell surface positive electroactivity by upregulating the starch and sucrose metabolism and the cationic antimicrobial peptide resistance pathways to counteract the adsorption and contact of Ag NPs and silver ion. These findings will guide improvements in aerobic denitrification processes in NP-polluted aquatic environments and facilitate the broader application of aerobic denitrification technologies.
研究领域:
微生物学
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环境科学
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分子生物学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Xingxing Peng,Qihang Zheng,Lei Liu,Yuzhe He,Tianyu Li,Xiaoshan Jia
T2, a gram-positive bacterium capable of rapidly degrading tetrabromobisphenol A (TBBPA), and affiliated with the genus Enterobacter , was isolated for the first time from sludge that had been contaminated for several years. The TBBPA degradation data fitted the first-order model well. Under optimal conditions (pH of 7, temperature of 31 °C, TBBPA concentration of 5 mg L −1 , and inoculum size of 5%), 99.4% of the initially added TBBPA was degraded after 48 h. TBBPA degradation fitted the first-order model with the half-life of 3.3 h. These results illustrated that the TBBPA degradation capability of strain T2 was significantly better than that of previously reported bacteria. A total of 17 intermediates were detected, among which five were reported for the first time. Whole-genome sequencing revealed that strain T2 had a chromosome with the total length of 4 854 376 bp and a plasmid with the total length of 21 444 bp. It harbored essential genes responsible for debromination, such as cyp450 , gstB , gstA , and HADH, and genes responsible for subsequent complete mineralization , such as bioC , yrrM , Tam , and Ubil . A key protein of haloacid dehalogenases responsible for the biodegradation of TBBPA may also be involved in the regulation of TBBPA degradation in natural environment. In soil bioremediation experiments, strain T2 showed excellent environmental adaptation. It was able to biodegrade TBBPA and its typical intermediate bisphenol A efficiently. Therefore, it could potentially be applied to treat TBBPA-contaminated sites.
研究领域:
环境科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
Cell Discovery
·
2021
·Vol. 7
·期 1
·1-12
·
IF 10.849
Meng Wensi,Zhang Lijie,Cao Menghao,Zhang Yongjia,Zhang Yipeng,Li Ping,Kang Zhaoqi,Guo Shiting,Xu Ping,Ma Cuiqing,Gao Chao
Overflow metabolism-caused acetate accumulation is a major problem that restricts industrial applications of various bacteria. 2,3-Butanediol (2,3-BD) synthesis in microorganisms is an ancient metabolic process with unidentified functions. We demonstrate here that acetate increases and then decreases during the growth of a bacterium Enterobacter cloacae subsp. dissolvens SDM. Both bifunctional acetaldehyde/ethanol dehydrogenase AdhE-catalyzed ethanol production and acetate-induced 2,3-BD biosynthesis are indispensable for the elimination of acetate generated during overflow metabolism. 2,3-BD biosynthesis from glucose supplies NADH required for acetate elimination via AdhE-catalyzed ethanol production. The coupling strategy involving 2,3-BD biosynthesis and ethanol production is widely distributed in bacteria and is important for toxic acetate elimination. Finally, we realized the co-production of ethanol and acetoin from chitin, the second most abundant natural biopolymer whose catabolism involves inevitable acetate production through the coupling acetate elimination strategy. The synthesis of a non-toxic chemical such as 2,3-BD may be viewed as a unique overflow metabolism with desirable metabolic functions.
研究领域:
微生物学
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代谢工程
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产品关联
DOI
PubMed
高影响因子
PHYSIOLOGICAL AND MOLECULAR PLANT PATHOLOGY
·
2024
·
IF 2.8
Zhe Han,Shengyi Wang,Ao Gao,Meiqi Dong,Yufeng Xiao,Hongyu Pan,Lining Zheng,Hao Zhang
Tomato wilt disease, caused by Fusarium oxysporum f. sp. lycopersici , is a major soil-borne disease affecting tomato cultivation. In this study, two strains exhibiting significant control effects on F. oxysporum f. sp. lycopersici and tomato growth-promoting effects were isolated from the rhizosphere. Through physiological and biochemical identification, as well as 16S rRNA identification, these strains were identified as Enterobacter quasihormaechei L33 and Klebsiella oxytoca TL2, respectively. And the two strains of bacteria were confirmed to have no antagonistic effect through antagonistic compatibility tests. Notably, when these strains were mixed in a ratio of 5:1, they demonstrated remarkable antifungal activity. The mixed strains induced mycelium swelling, necrosis, and rupture in F. oxysporum f. sp. lycopersici , resulting in a 56.65 % inhibition of mycelial fresh weight. Additionally, they inhibited spore production with an inhibition rate of 787.5 %, and the inhibition rate of the lipopeptide produced reached 93.80 % at 50 mg/mL. Furthermore, in potting experiments, the mixed strains reduced the disease incidence by 36.25 % after 8 weeks. Additionally, compared to the control group, the mixed bacterial strain group enhanced fresh weight, plant height, chlorophyll a and b levels, and root activities by 96.31 %, 18.51 %, 184.48 %, 53.03 %, and 44.31 %, respectively. In addition, mixed strains can inhibit the cell wall degrading enzymes produced by Fusarium oxysporum f sp., induce plant defense enzymes, including increased activity of peroxidase, catalase, and superoxide dismutase, and reduce the decrease in malondialdehyde levels. The mixed strains could colonize tomato plant roots. Overall, these findings suggest a potential biocontrol agent deriving from the mixed strains against tomato wilt disease.
研究领域:
植物病理学
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微生物学
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DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2025
·
IF 4.7
Xiaoming Li,Guopeng Zhu,Shaoqing Zhang,Xiutao Yang,Haibin Niu,Feng Zhu,Hongwen Yu
The massive consumption of primary energy sources has exacerbated the global energy crisis and environmental degradation, making the development of renewable alternatives imperative. Hydrogen energy, as a clean and renewable secondary energy source, offers a promising alternative. Among various strategies for sustainable hydrogen production, solar-driven whole-cell microbial biohydrogen synthesis stands out as a highly attractive approach. Here, we constructed a light-driven intracellular inorganic-biological hybrid system to boost hydrogen production. Specifically, the incorporation of C 3 N 4 quantum dots (QDs) into Enterobacter aerogenes enhanced photo-induced electron separation and transfer, achieving a hydrogen yield of 8.6 mL in a 25 mL reactor within 3 h, which is 52.3 % increase over the bacterial-only system. This work provides valuable insights into integrating the light-harvesting properties of inorganic nanomaterials with the metabolic machinery of microorganisms for efficient solar-to-chemical energy conversions.
研究领域:
可再生能源
·
纳米生物技术
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微生物代谢
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太阳能转化
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）