BMC Veterinary Research
·
2015
·Vol. 11
·期 1
·1-7
·
IF 1.777
Qu Ying,Qiu Zhenzhen,Cao Changfu,Lu Yan,Sun Meizhen,Liang Chaoping,Zeng Zhenling
Background Marbofloxacin is a third-generation fluoroquinolone developed solely for veterinary medicine with a broad spectrum of antibacterial activity against some Gram-positive and most Gram-negative bacteria, including the bovine respiratory tract pathogen, Pasteurella multocida. The objective of our study was to elucidate the pharmacokinetics and pharmacodynamics of marbofloxacin in a Pasteurella multocida infected murine lung model, and to estimate the magnitudes of pharmacokinetics-pharmacodynamics parameters associated with various effects.Results The pharmacokinetic studies revealed marbofloxacin kinetics in infected mice were linear over a dose ranging from 1.25 to 10 mg/kg of body weight. The protein binding in the plasma of neutropenic infected mice was 29.77 %. The magnitudes of the ratio of the free-drug area under the concentration-time curve over 24 h to MIC (fAUC0-24h/MIC) associated with static effect, a 2 log10 reduction and a 3 log10 reduction of bacterial counts were 40.84, 139.34, and 278.08 h, respectively.Conclusion sBased on the dose range study, marbofloxacin exhibited concentration-dependent killing and the fAUC/MIC was the PK/PD index that correlated best with efficacy (R2 = 83 %). On the basis of a bactericidal effect goal of fAUC0-24h/MIC of 278.08 h, if marbofloxacin is used for the treatment of P. multocida serious lung infection with an MIC90 of 0.12 μg/ml, the current dose (2 mg/kg) would fail to achieve a bactericidal effect. It would benefit from higher doses (4 ~ 6 mg/kg) than those commonly used in clinical practice.
研究领域:
兽医学
·
微生物学
·
药物研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FEMS MICROBIOLOGY LETTERS
·
2018
·Vol. 365
·期 24
·
IF 1.735
Wang Youping,Liu Cheng,Wan Juan,Sun Xiaowen,Ma Wei,Ni Hong
An organophosphorus-degrading bacterium MEW06, which exhibited excellent biodegradation capabilities towards 50 mg/L of methyl parathion (MP), paraoxon and dimethoate, was isolated from Sand Lake (Wuhan, China) and identified as Serratia marcescens subsp. marcescens based on physiological–biochemical characteristics and a 16S rDNA sequence-based phylogenetic tree. MEW06 genome contains a 31.09-kDa methyl parathion hydrolase (MPH) (MPHGM004539) that was 54.9% similar to Pseudomonas sp. WBC-3’s MPH. RT–qPCR revealed that mphGM004539 gene expression was significant up-regulated when co-cultured with MP. mphGM004539 without signal peptide (mphGM004539Δsp) was successful cloned and expressed in Escherichia coli BL21 (DE3). Optimized specific enzyme activity of MPHGM004539ΔSP was 5.26 U/mg under 35°C and pH 11.0 conditions when MP as the substrate. Additionally, Co2+, Cd2+and Fe2+ increased the enzyme activity level. MP could be degraded by MPHGM004539ΔSP into p-nitrophenol probably by hydrolyzing the P–O ester bond. Virulence of MP towards Drosophila melanogaster W1118 was reduced by MEW06 or MPHGM004539ΔSP biodegradation. This is the first cloning and characterization of MPH from the organophosphorus-degrading bacterium S. marcescens. MEW06 and its MPH have potential roles in the bioremediation of organophosphorus pesticide-contaminated eco-systems.
研究领域:
微生物学
·
环境科学
·
生物化学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2021
·
IF 3.757
Haiqing Chen,Fan Yu,Nan Shi,Pingping Du,Shuang Liu,Xianzhou Zhang,Jianxin Tan
A novel lipase gene ( lipA ) from Serratia marcescens L1 was cloned and expressed in Escherichia coli . LipA was shown to consist of 614 amino acid residues with seven residues that are different from the other nine reported lipases from S. marcescens . The activity of recombinant lipA based on a 50-mL culture scale approached 28 U/mL, which was more than that of the endogenous extracellular lipase from strain L1. The purified lipA fusion with a His-tag exhibited optimum activity at 30 °C and pH 8.0. Four effective mutants of lipase were obtained by site-directed mutation (SDM). The replacement of residues Arg552 and Gly2 in the enzyme molecule may play an important role in the catalysis characteristics and be responsible for the changes in thermostability and catalytic efficiency in the mutants. Mut G2P had the highest catalytic efficiency ( k cat / K m ) which was enhanced by 2.4-fold compared with its wild-type predecessor. These results indicated that lipA from S. marcescens could be expressed at a high level in E. coli and could be optimized by SDM, which provides a feasible basis for further study of its application.
研究领域:
微生物学
·
生物化学
·
基因工程
✓ 已验证
产品关联
DOI
高影响因子
GEOCHIMICA ET COSMOCHIMICA ACTA
·
2025
·
IF 5
Qingyi Cao,Junyi Liu,Jicheng Xia,Jen-How Huang,Susan Glasauer,Haiyan Hu,Xinbin Feng
Mineral-associated mercury (Hg), predominantly as mercury sulfide (HgS), represents the largest environmental Hg reservoir and is typically considered immobile and inert. Here, we reveal a novel microbe-mediated mechanism for the bioleaching of crystalline HgS via cysteine secreted by microorganisms. Hg-resistant bacterial strains Arthrobacter sp. WS-B1, Massilia sp. WS-B3, and Serratia sp. WS-B5, isolated from Wanshan mining soils in China, were found to secrete cysteine, which promotes the disintegration of crystalline HgS into HgS nanoparticles (HgSNPs), dissolved Hg, and ultimately volatile Hg(0). Utilizing transmission electron microscopy with energy-dispersive X-ray spectroscopy, HgS breakdown was evidenced through the detection of HgSNPs and a broadened Hg:S ratio range from 1.08 ± 0.05 to 0.33–1.58. Time-of-flight secondary ion mass spectrometry analysis revealed the co-localisation of C 3 H 7 NO 2 S and Hg, indicating Hg–cysteine complexation. These complexes inhibited Hg precipitation, maintaining its bioavailability for crops, while also enabling photoreduction via ligand-to-metal charge transfer upon irradiation to detoxify soil Hg. This study sheds light on the microbial transformation of crystalline HgS, the formation pathways of HgSNPs in nature, and the enhanced bioavailability of Hg previously considered inert
研究领域:
环境微生物学
·
地球化学
·
环境科学
·
生物地球化学
·
微生物生态学
✓ 已验证
产品关联
DOI
高影响因子
Synthetic and Systems Biotechnology
·
2025
·
IF 4.4
Wei Li,Di Liu,Linbo Gou,Shengfang Wu,Xiuwen Zhou,Tai-Ping Fan,Long Wang,Yujie Cai
(-)-α-Bisabolol, a valuable monocyclic sesquiterpene alcohol, has garnered significant attention in the pharmaceutical and cosmetic industries due to its remarkable anti-inflammatory, antibacterial, and skin-care properties. In this study, Serratia marcescens HBQA7 ( S. marcescens HBQA7), a non-model strain resistant to terpenoid toxicity, was used as the production host, and the expression intensities of different integration sites were screened. The complete (-)-α-bisabolol synthesis pathway was integrated into these sites, achieving a production titer of 3.5 g L −1 . On this basis, by knocking out competitive pathway genes (such as slaB and adhE ) and global regulatory factors ( arcA and iclR ), and introducing efficient glucose transport and activation ( glf and glk ), the shake flask fermentation titer was increased to 7.21 g L −1 . Through optimization of fermentation culture by orthogonal experiments and others, the titer was further increased to 9.90 g L −1 . Finally, through the fed-batch fermentation process conducted in a 50 L bioreactor, a titer of 102.3 g L −1 was achieved after 110 h of cultivation. The productivity reached 0.93 g L −1 h −1 . This study not only establishes the most efficient microbial production system for (-)-α-bisabolol reported to date, but also demonstrates the outstanding potential of S. marcescens as a chassis for terpenoid biosynthesis. It provides a novel strategy for the industrial production of high-value terpenoids.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL PHARMACOLOGY
·
2025
·
IF 5.6
Minzhuo Liu,Shuiqing Wu,Jie Zhang,Jia Yang,Jun Chen,Dariusz C. Górecki,Zhihong Zeng
Several secondary metabolites from Serratia marcescens have been reported to show a wide range of cytotoxic and potential antitumor activities. In this study, a novel derivative of bacterial biopigment (Serratin A) was isolated and its structure was characterized using ultraviolet (UV) spectra, infrared (IR) spectra, electronic circular dichroism (ECD) spectra, mass spectrometry (MS) spectra and nuclear magnetic resonance (NMR) spectra. The in vitro assays demonstrated its anticancer activity against the MDA-MB-231, MCF-7, and 4 T1 human and mouse breast cancer cell lines. Transcriptomic analyses in MCF-7 cells treated with serratin A (SA) identified specific gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) pathways in differentially expressed genes, particularly the apoptosis pathways enrichment. AnnexinV/propidium iodide staining confirmed apoptosis induction, and the mitochondrial membrane potential (ΔΨm) assay found the ΔΨm value diminished in serratin A-treated cells. Moreover, serratin A treatment increased the pro-apoptotic Bax and Caspase 3/9 while inhibited the anti-apoptotic gene Bcl-2 gene expression in a dose-dependent manner. Finally, serratin A treatment in vivo in MCF-7 tumor-bearing mice showed a dose-dependent tumor growth inhibition accompanied by increased apoptosis. Taken together, we have identified a new compound from Serratia marcescens that exhibits anticancer properties both in vivo and in vitro and has a potential for therapeutic applications in cancer.
研究领域:
微生物学
·
药理学
·
肿瘤学
·
生物化学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2022
·
IF 6.056
Jin-Wei Zhou,Peng-Cheng Ji,Chang-Yao Wang,Yu-Jie Yang,Xin-Yu Zhao,Hao-Zhe Tang,Shi-Rong Tang
Serratia marcescens NJ01 and Erwinia carotovora , two pathogenic bacteria involved in vegetable spoilage, can persist in leafy vegetables and subsequently form biofilms. The aim of this study was to evaluate the effect of propyl gallate (PG) on the susceptibility of antibiotics against the biofilms of S. marcescens NJ01 and E. carotovora and uncover its anti-virulence mechanism. PG notably inhibited the production of AHLs and enhanced the susceptibility of antibiotics against the biofilm formation of S. marcescens NJ01 and E. carotovora and significantly improved the disrupted effect on the preformed biofilms of S. marcescens NJ01. PG exposure decreased the minimum inhibitory concentrations of these five antibiotics and reduced the production of virulence factors. Further investigation indicated that PG exposure resulted in the downregulation of genes involved in virulence, biofilm formation, and antioxidant enzymes of S. marcescens NJ01. The suppression of antioxidant enzymes caused the enhancement of oxidative stress, increased membrane permeability, and ultimately promoted the susceptibility of bacterial/biofilm cells to antibiotics. The tomato and lettuce infection assay indicated that PG could notably attenuate the pathogenicity of S. marcescens NJ01 and E. carotovora . These findings suggest that PG has the potential to function as an antibiotic accelerant to defend against spoilage pathogens.
研究领域:
微生物学
·
食品科学
·
植物病理学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Linna Du,Xinjiao Dong,Huan Wu,Gang Li,Jiacheng Zhou,Yiqing Wu,Yanping Xiao,Jing Qin,Xiu Wang
The activated sludge process exhibits limited efficacy in decolorizing triphenylmethane (TPM) dyes like malachite green (MG) in textile wastewater. This study demonstrates that bioaugmentation with Serratia sp. strain WKD significantly enhances MG removal in activated sludge systems. Within 2 h, the combined system (activated sludge + strain WKD) achieved 98.5 ± 0.1 % decolorization efficiency—a 5.3-fold increase over sludge-only controls (18.5 ± 1.7 %). High-throughput sequencing revealed strain WKD's ecological dominance, reducing microbial alpha diversity (8 h) through competitive exclusion. When coupled with carboxymethyl cellulose-modified nano-zero-valent iron (CMC-nZVI), the hybrid system synergistically enriched stress-tolerant degraders ( Serratia sp. and Pseudomonas sp.), thereby accelerating decolorization. Prolonged incubation (24 h) enabled microbial diversity recovery (Shannon and Simpson indices) as detoxification alleviated environmental stress. Functional profiling identified pathway-specific modulation: critical metabolic functions (e.g., carbohydrate/amino acid metabolism) were transiently suppressed, while membrane transport activity remained intact, preserving system functionality. These findings establish strain WKD and CMC-nZVI as a synergistic bioaugmentation strategy, enabling rapid dye removal while maintaining microbial community resilience through dynamic stress-response mechanisms.
研究领域:
环境生物技术
·
微生物生态学
·
水处理
·
纳米技术
·
生物修复
✓ 已验证
产品关联
DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2024
·
IF 3.1
Zhao Jielin,Li Xiaolian,He Ranfeng,Wang Yunshan,Wang Ziqiang
This study aimed to develop a multienzymatic system for synthesis of l -malate. First, recombinant Escherichia coli strains were constructed expressing maleic acid cis – trans isomerase (MaiA) or fumarase C (FumC) from different sources. Serratia marcescens MaiA (SMaiA) and E. coli FumC (ECFumC) showed good catalytic performance. Next, six co-expression systems for SMaiA and ECFumC were constructed. E. coli BL21 (DE3)-pRSF Duet-1 - ecfumC-smaiA (named strain pFM2) had the highest l -malate catalytic activity. In 7-L fed-batch fermentation, the SMaiA and ECFumC activities of strain pFM2 wet cells were 43.4 and 154.5 U/g, respectively, 2.4- and 10.7-fold the values that were obtained in shaken flasks. Finally, a whole-cell catalytic process was established for the production of l -malate by strain pFM2 with maleate as the substrate. When the dose of pFM2 wet cells was 0.5 g/100 mL and 1 mol/L maleate was the substrate, the catalytic process was completed within 4 h. Notably, the intermediate fumarate was almost absent during the conversion process. The concentration of l -malate reached 143.8 g/L with a yield of 0.60 g/(L·min). The molar conversion rate of the substrate was 98.4%. These findings lay a foundation for the industrial application of multienzymatic synthesis of l -malate. Graphical Abstract
研究领域:
生物技术
·
生物化工
·
代谢工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
·
2025
·
IF 6.3
Xue Li,Dongwen Fu,Shuai Hu,Jinqing Huang,Li Wang,Yao Zhang,Cailing Liu,Bo Dong,Guangxian Liu
Non-contact preservation of meat remains a challenging and active area of research in the food industry. In this study, a non-contact solid spice essential oils preservative (SSEP) was developed and combined with modified atmosphere packaging (MAP, 30 % CO 2 + 70 % N 2 ) for the preservation of chilled fresh chicken. The results showed that SSEP, with essential oils (EOs) loading capacity of 29.49 % (rosemary: cinnamon = 1:1, w/w), exhibited significant antibacterial activity against both Staphylococcus aureus and Escherichia coli . Storage tests demonstrated that the combination of SSEP and MAP effectively delayed spoilage of chicken breast samples, as evidenced by a decrease in total volatile basic nitrogen (TVB-N), total viable count (TVC), and thiobarbituric acid reactive substances (TBARS) by 16.19 %, 32.21 % and 21.28 %, respectively, compared to the MAP-only group after 14 days of storage. High-throughput sequencing revealed that Pseudomonas spp. was the predominant bacteria in control group, while Carnobacterium spp., Serratia spp. and Lactococcus spp. were the predominant bacteria in MAP group. The combination of SSEP and MAP significantly reduced the relative abundance of spoilage bacteria and extended the shelf life by inhibiting the growth of Pseudomonas spp., Carnobacterium spp., Serratia spp. and Lactococcus spp. These findings propose a promising approach for non-contact meat preservation, enhancing the safety and quality of poultry products during refrigerated storage.
研究领域:
食品科学
·
食品保鲜
·
食品微生物学
·
食品安全
·
应用微生物学
✓ 已验证
产品关联
DOI
高影响因子
MEAT SCIENCE
·
2025
·
IF 6.1
Mengjiao Han,Qianhui Gu,Sam Al-Dalali,Conggui Chen,Baocai Xu,Peijun Li
This study aimed to investigate the change of volatile organic compounds (VOCs) in fresh beef sausages during refrigerated storage and assess the relationship between VOC levels and microbial population. Forty-one VOCs were detected using headspace solid-phase microextraction coupled with gas chromatography-olfactometry-mass spectrometry (GC-O-MS). The results of the 16S rDNA amplicon sequencing indicated that the spoilage bacteria predominated were Brochothrix and Serratia . Acetoin, hexanal and 1-octen-3-ol were significantly positively related to Brochothrix (Mantel's r = 0.95, p = 0.017) and Serratia (Mantel's r = 0.81, p = 0.024) levels. As the key VOCs, these three compounds may serve as spoiling indicators for tray-packed fresh beef sausages. This study elucidates the production of VOCs by microbial roles in fresh beef sausages and offers insights for prolonging the shelf life.
研究领域:
食品科学
·
食品微生物学
·
分析化学
·
肉类科学
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Wangli Dai,Shulai Liu,Yicheng Ding,Saiqi Gu,Xuxia Zhou,Yuting Ding
The flavor alterations in bighead carp subjected to varying storage temperatures and the underlying metabolic mechanism were elucidated. Analysis of volatile flavor compounds, electronic nose, free amino acids , ATP-related compounds, and sensory evaluations uncovered a progressive flavor deterioration during storage, especially at 25 °C. Metabolomics-based flavor relating component profiling analysis showed that free fatty acids formed various fatty aldehydes including (E, E)-2,4-heptadienal and nonanal under lipoxygenase catalysis. Alcohol dehydrogenase and alcohol acyltransferases were intimately involved in alcohol and ester generation, while alkaline phosphatase, 5′-nucleotidase, and acid phosphatase were closely associated with IMP, Hx, and HxR conversion, respectively. Aeromonas , Serratia , Lactococcus , Pseudomonas , and Peptostreptococcus notably influenced flavor metabolism and enzyme activities. The metabolism disparities of valine , leucine , isoleucine , lysine, and α-linolenic acid could be the primary factors contributing to flavor metabolism distinctions. This study offers novel insights into the flavor change mechanisms and potential regulation strategies of bighead carp during storage.
研究领域:
食品科学
·
生物化学
·
微生物学
·
代谢组学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）