BIOCHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 3.8
Xinying Sun,Wei Xiao,Mengying Wu,Fuqiang Liu,Jiaxin Li,Lei Liu,Jing Wu,Keke Cheng,Jianan Zhang
Microbial fermentation technology has advanced rapidly in the field of green chemical production, showcasing broad application prospects. However, current techniques still face challenges such as low carbon utilization efficiency and excessive accumulation of by-products. Additionally, during the fermentation process, carbon sources are released in the form of CO₂, leading to significant carbon loss. In this study, Enterobacter cloacae CICC 10011 was metabolically engineered to achieve the co-production of 2,3-butanediol (2,3-BDO) and lactic acid, while reducing carbon dioxide emissions and improving carbon utilization. By knocking out key genes ( pflB and iclR ), the pathways for the formation of by-products such as formate, acetate, and ethanol were attenuated, thereby optimizing carbon flux toward the target products. The results showed that under optimal fermentation conditions (aeration rate of 0.4 vvm, pH 6.5, temperature 35 °C), the double-gene deletion strain ECΔpflBΔiclR achieved lactic acid and 2,3-BDO (mixture of stereoisomers) concentrations of 51.03 g/L and 10.44 g/L, respectively, with a total target product yield of 1.76 mol/mol. Compared to the wild-type strain, the production of by-products succinate, acetate, and ethanol was reduced by 70.04 %, 47.10 %, and 89.76 %, respectively. Additionally, CO₂ emissions were reduced by 68.92 %, and carbon conversion efficiency improved by 116.16 %. This strategy provides a novel approach for carbon emission reduction and the co-production of high-value chemicals in fermentation processes.
研究领域:
微生物学
·
代谢工程
·
工业生物技术
·
发酵工程
·
绿色化学
·
生物制造
·
碳代谢
✓ 已验证
产品关联
DOI
高影响因子
MICROBIAL PATHOGENESIS
·
2021
·
IF 3.738
Cao-wei Chen,Lei Yuan,Yuan-song Zhang,Fedrick C. Mgomi,Yang Wang,Zhen-quan Yang,Xin-an Jiao
Enterobacter hormaechei is a zoonotic bacteria that may cause respiratory diseases in animals and neonatal sepsis in humans. Bacteriophages are increasingly considered as potential biocontrol agents to control pathogens in the food industry. In this study, five E. hormaechei virulent phages, named as Ehp-YZU08, Ehp-YZU10, Ehp-YZU9-1, Ehp-YZU9-2 and Ehp-YZU9-3, were isolated from sewage in China and analyzed for their biological and whole-genome characteristics, and a comparative genomic analysis was performed to study the functional genes and phylogenetic evolution of phages. The results showed that four of the phage strains belong to the Podoviridae family and one belongs to the Myoviridae family. The burst sizes were 70–283 PFU/cell after a latent period of 5–40 min. Phages were able to survive in a pH range of 5–10 and resist temperatures up to 60 °C for 60 min. The sequencing results showed that the full length of the genomes of the five phages ranged from 39,502 to 173,418 bp. Each phage contained multiple genes related to phage replication, and genes related to bacterial virulence or drug resistance were not found. The five phages belonged to three different groups by a construction of a phylogenetic tree , and the significant genetic evolutionary distance from each E. hormaechei phage was observed. The inhibition assay showed that all five phages could completely inhibit the growth of E. hormaechei at 37 °C within 8 h, suggesting that the phages in this study have great potential for the development of biocontrol agents against E. hormaechei in the food industry.
研究领域:
微生物学
·
基因组学
·
食品科学
·
噬菌体疗法
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
·
2021
·
IF 4.32
Xiao Zhou,Min Zhou,Shengjun Ye,Yanbin Xu,Shaoqi Zhou,Qiujie Cai,Guangyan Xie,Lu Huang,Li Zheng,Yuxin Li
The antibacterial activity and mechanism of reduced graphene oxide (rGO)-modified TiO 2 were assessed against Enterobacter hormaechei in this study. The rGO-modified TiO 2 exhibited an enhanced antibacterial activity against E. hormaechei under UV–Visible light irradiation compared with individual TiO 2 or rGO alone. Its effectiveness owed to the synergistic effect of the improved adsorption and the lower recombination of photo-induced electron–hole pairs. The hybrid photocatalyst improved charge separation and chemical binding activity that contributed to accelerated antibacterial process. The flow cytometry results showed that the hybrid photocatalyst reduced the survival ratio of E. hormaechei to about 10% with 90 min under visible light illumination. The XPS spectra and SEM micrographs indicated a direct physical contact and disruptive interaction between the bacteria and the rGO-TiO 2 catalyst, mostly on rGO, resulting in oxidizing a vital cellular structure. EPR measurement revealed that hydroxyl radicals were the dominant active species that can cause the peroxidation of lipids in the outer cell wall and the damage of cell organelles and components inside the bacteria, which is the key mechanism for this antibacterial process. Overall, this study indicated that rGO-modified TiO 2 nanocomposite has great potential as an economical, environmentally friendly and easily available antibacterial material for antibacterial.
研究领域:
材料科学
·
纳米技术
·
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 6
·期 2
·1279-1287
·
IF 3.84
Xuan Zhang,Jun Zhou,Chundan Zhang,Dijun Zhang,Xiurong Su
To establish the rapid detection of Enterobacter cloacae in food, immunomagnetic beads were prepared by coupling an anti-E. cloacae polyclonal antibody with magnetic beads. An immunochromatographic test strip was composited with an anti-E. cloacae monoclonal antibody marked by colloidal gold as the detection antibody, anti-E. cloacae polyclonal antibody as the test line, and donkey anti-mouse IgG secondary antibody as the control line. Immunomagnetic separation was combined with a colloidal gold-based immunochromatographic assay for the rapid detection of E. cloacae. The results showed that 102 CFU mL−1 E. cloacae could be detected using the immunochromatographic test strip after immunomagnetic separation. The sensitivity was 10 times higher than direct detection with an immunochromatographic test strip. With the immunochromatographic test strip, water samples spiked with E. cloacae yielded a negative result, whereas E. cloacae yielded a positive result with immunomagnetic separation. The proposed method enhances the rapid detection of E. cloacae in food.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Yulei Zhang,Zhaolin Huang,Wenli Zhang,Dawei Ni,Wei Xu,Cuie Guang,Wanmeng Mu
The presence of macrolides in food and the environment poses a substantial threat to the sustainable development of natural ecosystems and presents risks to human health. Previous research has demonstrated that microbial esterases can degrade erythromycin (Ery), roxithromycin (Rox), and clarithromycin (Clr), rendering them candidates for bioremediation of macrolide residues. However, the efficacy of esterases is limited by insufficient thermal stability, restricting their widespread application. To address this challenge, this study employed a combinatorial strategy integrating computational molecular dynamics (MD) simulations, server-assisted virtual mutation prediction, and a greedy algorithm for protein engineering to enhance the thermal stability of esterase C from Enterobacter hormaechei ( Ehno -EreC). After four rounds of screening, we successfully obtained a four-point mutant, M4 (D245P/S141A/D154I/T292W), which exhibited significantly improved thermal stability compared to the wild-type enzyme. Notably, the M4 mutant not only extended the enzyme's half-life at 40 °C from 7 to 1095 min, but also increased its degradation activity against Ery, Rox, and Clr. Structural analyses revealed enhanced rigidity in the loop between the major and minor lobes and the strengthened hydrophobic interactions post-mutation, contributing to the enzyme's structural stability. This finding was consistent with the observed reduction in correlated and anti-correlated motions in the MD trajectory.
研究领域:
生物化学
·
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2026
·
IF 4
Shan Ye,Chenxi Xiang,Beibei Luo,Ruoyu Zhang,Yao Wang,Jinglei Chen,Zhuhong Yang,Zhong Ding
The rice root-knot nematode Meloidogyne graminicola causes severe yield losses in rice production, requiring eco-friendly control measures. Here, we isolated Enterobacter asburiae SA-9 from rice rhizosphere soil and evaluated the biocontrol potential of its volatile organic compounds (VOCs) against M. graminicola . In vitro, SA-9 VOCs exhibited potent fumigant activity, causing high mortality of second-stage juveniles (J2s) and significant inhibition of egg hatching. Chemotaxis assays showed that SA-9 disrupted nematode chemotaxis through repellent activity. Further investigations revealed that exposure to SA-9 VOCs significantly downregulated key chemosensory genes ( Mg-odr-1 , Mg-odr-3 , Mg-osm-9 , Mg-tax-4 ) in J2s, impairing their host-seeking and infection abilities. In double-layered pot, SA-9 VOCs effectively reduced root gall index and nematode populations, while concurrently promoting rice growth, accompanied by upregulation of auxin ( OsAUX1 , OsYUCCA1 ) and gibberellin ( OsGID1 ) biosynthesis-related genes. Furthermore, SA-9 VOCs induced genes related to systemic resistance in rice, as evidenced by the increased expression of defense-related genes in the salicylic acid ( OsPR1a , OsWRKY45 ) and jasmonic acid ( OsAOS2 , OsMYC2 ) signaling pathways. SPME-GC–MS profiling identified 12 VOCs produced by SA-9, with 2-phenylethanol, 2-methylbutyric acid, isobutyric acid and propanoic acid exhibiting significant contact and fumigation nematicidal activities against J2s. These findings demonstrate that SA-9 VOCs suppress M. graminicola through multiple mechanisms, highlighting their potential as sustainable biocontrol agents for managing root-knot nematodes in rice agroecosystems.
✓ 已验证
DOI
PubMed
高影响因子
Frontiers of Environmental Science & Engineering
·
2025
·Vol. 19
·期 10
·1-10
·
IF 6.4
Zhang Ting,Yang Zhongwei,Li Haibei,Li Hui,Yang Yidi,Chen Tianjiao,Zhou Shuqing,Shi Danyang,Yang Dong,Li Junwen,Jin Min
The presence of the Enterobacter cloacae complex (ECC) in natural water bodies poses potential public health risks because these bacteria can enter humans from the environment within the “One Health” framework. Nevertheless, there is a notable deficiency in the isolation and knowledge of carbapenem- and polymyxin-resistant ECC strains from natural water bodies. In this research, 48 ECC strains were isolated from natural water bodies. Of these, eight strains were resistant to carbapenems (imipenem) and polymyxins (polymyxin B and colistin sulfate) and were classified as multi-locus sequence typing 13. Comparative genomic analysis identified bla CMY-63 , pmrE , pmrF , and various efflux pump genes as key genetic determinants of co-resistance to carbapenems and polymyxins. Notably, these strains exhibited relatively high virulence, with cell death rates ranging from 57% to 84%. They also exhibited virulence against Galleria mellonella . This research sheds light on the potential health risks of carbapenem- and polymyxin-resistant ECC strains displaying virulence in natural water bodies.
✓ 已验证
DOI
高影响因子
Food Bioscience
·
2021
·
IF 4.24
Yali Huang,Honghong Yu,Shiling Lu,Liangjun Zou,Zonggui Tang,Tao Zeng,Juan Tang
Ferulic acid inclusion complexes (FA-HP-β-CD) effects on tyramine accumulation and gene expression of Enterobacter hormaechei MW386398 in traditional smoked horsemeat sausages were studied. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to identify the expression of tyrosine decarboxylase (TDC) clusters in the tyramine producing pathway. In addition, relevant parameters such as microbial growth , moisture content, pH, and tyramine accumulation in pure cultures and during fermentation of smoked horsemeat sausages were evaluated. Ferulic acid (FA) and FA-HP-β-CD inclusion complexes both significantly decreased tyramine accumulation, as well as significantly inhibited tyrosine decarboxylase (tdcA) and tyrosine/tyramine antiporter (tyrP) genes expression ( p < 0.05). Furthermore, FA and FA-HP-β-CD inclusion complexes both reduced the number of Enterobacteriaceae in smoked horsemeat sausages, but did not alter the main microbiota . However, FA-HP-β-CD inclusion complexes exhibited stronger ability in hindering TDC related gene expression, reducing tyramine accumulation and antibacterial properties . These results indicate that FA-HP-β-CD inclusion complexes are able to reduce tyramine accumulation in smoked horsemeat sausages by inhibiting Enterobacteriaceae growth and gene expression.
研究领域:
食品科学
·
微生物学
·
分子生物学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
An-qi Tang,Xuechao Xu,Cao-wei Chen,Mengyuan Tan,Lu Gao,Zhen-quan Yang
Enterobacter hormaechei , A zoonotic pathogen with escalating prevalence in global food sources, severely jeopardizes food safety, necessitating the development of high-performance detection methods. Herein, a novel colorimetric detection strategy integrating phages and nanozymes was proposed for foodborne E. hormaechei . Initially, four homologous phages (EhpYZU05, EhpYZU08, EhpYZU9–1 and EhpYZU10), which were isolated using E. hormaechei YZU05 as the host bacterium, were modified on the surface of NH 2 -MIL-88B(Fe) to fabricate four phage@NH 2 -MIL-88B(Fe) nanozymes. These nanozymes exhibit peroxidase-like activity, catalyzing 3,3′,5,5′-tetramethylbenzidine (TMB) chromogenic reaction in presence of H 2 O 2 . With introduction of multiple host or non-host E. hormaechei strains, TMB chromogenic reaction catalyzed by phage@NH 2 -MIL-88B(Fe) nanozymes can be specifically inhibited. This inhibition occurs due to the specific phage adsorption of phage@NH 2 -MIL-88B(Fe) nanozymes towards these host or non-host E. hormaechei strains, indirectly blocking their catalytic sites. Leveraging this principle, colorimetric broad-spectrum detection of E. hormaechei was achieved. Additionally, this method demonstrated reliable recoveries (96.7 % ~ 103.3 %) when applied to detect real food matrices, highlighting its high reliability in practical scenarios. This approach not only clarifies the intrinsic mechanism of phage-modified nanozymes for target bacteria detection but also provides a robust and reliable method for early pathogen detection, thereby significantly contributing to food safety enhancement
✓ 已验证
产品关联
DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2022
·Vol. 24
·期 22
·8691-8704
·
IF 11.034
Xin Pan,Xue Wang,Sihua Wu,Lei Xu,Leilei Zhang,Zhan Zhang,Bingfeng Li,Xuejun He,Siyuan Chang
Upgrading of the bio-based platform chemical 5-hydroxymethylfurfural (HMF) into high-value derivatives is an important research topic, particularly in green and sustainable chemistry. Herein, we applied a new, highly HMF-tolerant strain, Enterobacter ludwigii YYP3, as a whole-cell biocatalyst for efficient reduction of HMF to 2,5-bis(hydroxymethyl)furan (BHMF). Upon process optimization, within only 3 h, BHMF was produced with a yield >99% and 98.5% selectivity using 100 mM HMF, resulting in the highest space time yield (4.2 g L−1 h−1) among the currently reported HMF bioreduction processes. In a fed-batch conversion, E. ludwigii YYP3 achieved large-scale production of 290 mM BHMF within 9 h and retained its high catalytic activity for three runs (27 h), suggesting an excellent cycling stability. Based on genome and transcriptome analysis, the molecular mechanism underlying the high HMF tolerance of E. ludwigii YYP3 was explored, primarily through the downregulation of genes related to amino acid biosynthetic and metabolic processes and upregulation of genes associated with DNA replication, recombination, and repair; biofilm formation; and redox homeostasis. Meanwhile, two novel short-chain dehydrogenase/reductase family oxidoreductases ElSDR-ykvO and ElSDR-SSP1627 were identified as target enzymes responsible for conversion of HMF to less toxic BHMF in E. ludwigii YYP3. Combined with structure and mutation analysis, the catalytic mechanisms of target enzymes were determined to be based on the active sites Ser, Tyr, and Lys. Our work not only confirms that E. ludwigii YYP3 has promising application prospects in large-scale production of BHMF, but also provides novel insights into understanding the molecular mechanism of HMF reduction.
研究领域:
生物催化
·
生物化学工程
·
分子生物学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Plant Science
·
2020
·
IF 4.402
Ji Chao,Liu Zhaoyang,Hao Liping,Song Xin,Wang Changdong,Liu Yue,Li Huying,Li Chaohui,Gao Qixiong,Liu Xunli
The present study investigated the physiological and biochemical characteristics of Enterobacter cloacae HG-1 isolated from saline-alkali soil. We further studied the effect of this strain on the salt tolerance of wheat and on the community structure of nitrogen-fixing bacteria in rhizosphere soil. We determined that the investigated strain had high nitrogen fixation activity and produced iron carriers, 1-aminocyclopropane-1-carboxylic acid deaminase, and plant hormones. The metabolites of this strain contained 2,3-butanediol, [R-(R*, R*)], 2-heptanone, and other growth-promoting and antibacterial substances. The strain was also highly salt-tolerant (10% NaCl). After the inoculation of wheat with the HG-1 strain, we recorded increases in root length, plant height, fresh weight, and dry weight of 19.15%, 18.83%, 16.67%, and 17.96%, respectively, compared with uninoculated plants (P < 0.05). Compared with the leaves of uninoculated plants, the proline concentration in the leaves of inoculated plants increased by 12.43% (P < 0.05), the malondialdehyde level decreased by 27.26% (P < 0.05), K+ increased by 20.69%, Ca2+ increased by 57.53% and Na+ decreased by 31.43% (all P<0.05). Furthermore, we detected that inoculation with the HG-1 strain did not affect the species composition of nitrogen-fixing bacteria in wheat rhizosphere soil at the phylum level. However, the average relative abundance of Proteobacteria was significantly increased, whereas the abundance of Verrucomiorobia was significantly decreased compared with uninoculated plants. At the genus level, we detected 32 genera in control samples and 27 genera in inoculated samples, and the species diversity and relative abundance of samples inoculated with the HG-1 strain decreased compared with uninoculated plants. Inoculated samples had lower abundances of Azospirillum, Rhodomicrobium, and Anabaena. Our study demonstrated that the inoculation of wheat with E. cloacae HG-1 could promote the growth of wheat under salt stress and increase salt stress tolerance. The results of this study investigating the interaction among soil, plants, and microorganisms supplement agricultural microbial databases and could provide a reference for the development of microbial-based saline soil improvement programs.
研究领域:
微生物学
·
农学
·
土壤学
·
植物生理学
✓ 已验证
DOI
PubMed
高影响因子
Microbiology Spectrum
·
2022
·
IF 9.043
Wenzhi Bao,Xing Li,Jinfeng Liu,Rong Zheng,Lijuan Liu,Haibo Zhang
Phenylpyruvate decarboxylase (PPDC) is a crucial enzyme that plays important roles in 2-phenylethanol (2-PE) biosynthesis. In our previous study, we screened a highly efficient PPDC KDC4427 from the novel 2-PE-producing strain Enterobacter sp. CGMCC 5087. Meanwhile, its decarboxylation activity of indolylpyruvate (IPyA) was also higher than other indolylpyruvate decarboxylases (IPDCs) reported so far. In this study, KDC4427 protein was purified and characterized, and its catalytic mechanisms were analyzed by biological methods. The optimum pH and temperature of KDC4427 was pH 6.5 and 35°C, respectively. The enzyme activity was relatively stable between pH 6 and 8 and over the range of temperatures from 25°C to 45°C. KDC4427 showed the highest catalytic efficiency on phenylpyruvic acid (PPA); meanwhile, it also showed high activity for IPyA and 2-ketobutanoic acid, and it was found that KDC4427 belongs to IPDCs by phylogenetic tree analysis. The coverage of the three-dimensional structure of KDC4427 and EcIPDC from Enterobacter cloacae was 96%. Leucine 542, one of the residues in the substrate-binding pocket, is replaced by isoleucine in KDC4427 compared with EcIPDC. Site-directed mutagenesis showed that the transition from leucine to isoleucine was unlikely to make KDC4427 have high catalytic activity for PPA and IPyA; the mutants at glutamate 468 almost completely lost catalytic activities for both PPA and IPyA, indicating that this glutamate was essential for the catalytic activity. Additionally, alanine 387 plays an important role in the substrate selectivity of KDC4427.IMPORTANCE Compared with the chemical synthesis of 2-phenylethanol (2-PE) by condensation of ethylene oxide and benzene, the biological synthesis of 2-PE is a potential method to replace the traditional process. This makes biotransformation gradually become the main way to produce high-quality 2-PE. Phenylpyruvate decarboxylase (PPDC) is the critical enzyme in 2-PE biosynthesis, and it is a momentous point of penetration to increase the production of 2-PE. In this regard, KDC4427 can catalyze phenylpyruvic acid (PPA) to phenylacetaldehyde more efficiently than any other PPDC previously reported. Moreover, it has high activity of indolepyruvate decarboxylases (IPDCs), which will be a great breakthrough in the synthesis of indole-3-acetic acid (IAA). With this study, we offer insights into the KDC4427 catalytic mechanism and significantly expand the toolbox of available α-ketoacid decarboxylases for application in biosynthesis.
研究领域:
生物化学
·
生物技术
·
酶学
·
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）