PLoS Pathogens
·
2025
·Vol. 21
·期 1
·e1012787
·
IF 4.9
Tingting Wang,Huaizhi Yang,Qiushuang Sheng,Ying Ding,Jian Zhang,Feng Chen,Jianfeng Wang,Lei Song,Xuming Deng
Hypervirulent Klebsiella pneumoniae (hvKP) poses an alarming threat in clinical settings and global public health owing to its high pathogenicity, epidemic success and rapid development of drug resistance, especially the emergence of carbapenem-resistant lineages (CR-hvKP). With the decline of the “last resort” antibiotic class and the decreasing efficacy of first-line antibiotics, innovative alternative therapeutics are urgently needed. Capsule, an essential virulence determinant, is a major cause of the enhanced pathogenicity of hvKP and represents an attractive drug target to prevent the devastating clinical outcomes caused by hvKP infection. Here, we identified isoferulic acid (IFA), a natural phenolic acid compound widely present in traditional herbal medicines, as a potent broad-spectrum K . pneumoniae capsule inhibitor that suppresses capsule polysaccharide synthesis by increasing the energy status of bacteria. In this way, IFA remarkably reduced capsule thickness and impaired hypercapsule-associated hypermucoviscosity phenotype (HMV), thereby significantly sensitizing hvKP to complement-mediated bacterial killing and accelerating host cell adhesion and phagocytosis. Consequently, IFA facilitated effective bacterial clearance and thus remarkably protected mice from lethal hvKP infection, as evidenced by limited bacterial dissemination and a significant improvement in survival rate. In conclusion, this work promotes the development of a capsule-targeted alternative therapeutic strategy for the use of the promising candidate IFA as an intervention to curb hvKP infection, particularly drug-resistant cases.
Hypervirulent Klebsiella pneumoniae (hvKP) is becoming an imminent threat to public health because of the constant emergence of drug resistance and its devastating clinical outcomes. Meanwhile, the both notorious phenotypes are integrated to create carbapenem-resistant and hypervirulent K . pneumoniae (CR-hvKP), which leads to a scarcity of effective treatments. Therefore, there is an increasing urgent need for new therapeutics other than antibiotics. The indispensable role of capsule in immune evasion and pathogenesis renders it a promising target for developing novel alternative strategies to combat hvKP infections. In this study, we identified the small natural compound isoferulic acid (IFA) as a potent broad-spectrum inhibitor of K . pneumoniae capsule. Hypercapsule-associated hypermucoviscosity (HMV), a characteristic phenotype that has been shown to play a distinct and critical role in the pathogenesis of hvKP, is significantly impaired by IFA. RNA-seq analysis revealed that IFA interferes with the biosynthesis of capsule polysaccharide through altering bacterial metabolism status. Consequently, IFA sensitizes hvKP to serum killing and impedes capsule- and HMV-mediated resistance to adherence and phagocytosis. In vivo, IFA treatment facilitates effective host clearance and thereby systemically protects mice against hvKP infection. Our research sheds light on the development of capsule-targeted drug and provides an effective lead compound that may contribute to the management of hvKP infections as an intervention.
研究领域:
微生物学
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传染病学
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药物开发
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产品关联
DOI
PubMed
高影响因子
Microbiology Spectrum
·
2022
·Vol. 10
·期 6
·
IF 9.043
Shuyi Wang,Qi Ding,Yawei Zhang,Anru Zhang,Qi Wang,Ruobing Wang,Xiaojuan Wang,Longyang Jin,Shuai Ma,Hui Wang
Carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) is recognized as a threat worldwide, but the mechanisms underlying its emergence remain unclear. As most CR-hvKP isolates are not hypermucoviscous, we speculated that the evolution of the capsule might result in the convergence of carbapenem resistance and hypervirulence. Here, 2,096 K. pneumoniae isolates were retrospectively collected to screen the ST23-K1 clone, and hypervirulence was roughly defined as being highly resistant to serum killing. The effect of wcaJ on the capsule, virulence, fitness, and resistance acquisition was further analyzed. The capsule gene wcaJ, inserted by ISKpn26/ISKpn74, was identified via whole-genome sequencing in four hvKP, but not hypermucoviscous, isolates. Uronic acid quantitation results revealed that these isolates produced significantly less capsular polysaccharides than NTUH-K2044. A significant increase in capsular production was observed in wcaJ-complemented isolates and confirmed by transmission electron microscopy. Further, all wcaJ-complemented isolates acquired greater resistance to macrophage phagocytosis, and one representative isolate resulted in a significantly higher mortality rate than the parental isolate in mice, indicating that wcaJ inactivation might compromise virulence. However, isolates with wcaJ interruption demonstrated a lower fitness cost and a high conjugation frequency of the blaKPC-2 plasmid, raising concerns about the emergence of carbapenem resistance in hvKP.IMPORTANCE Klebsiella pneumoniae is one of the most common nosocomial pathogens worldwide, and we speculated that the evolution of the capsule might result in the convergence of carbapenem resistance and hypervirulence of K. pneumoniae. The wcaJ gene was first reported to be interrupted by insertion sequence elements in ST23-K1 hypervirulent Klebsiella pneumoniae, resulting in little capsule synthesis, which plays an important role in virulence. We examined the effect of wcaJ on the capsule, virulence, and fitness. Isolates with wcaJ interruption might compromise virulence and demonstrated a lower fitness cost and a high conjugation frequency of the blaKPC-2 plasmid, highlighting its role as a potential factor facilitating hypervirulence and carbapenem resistance.
研究领域:
微生物学
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感染病学
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基因组学
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DOI
高影响因子
FEMS MICROBIOLOGY LETTERS
·
2015
·Vol. 362
·期 6
·
IF 2.121
Zhao Jianqing,Pan Shan,Lin Lan,Fu Lei,Yang Chao,Xu Zhongmin,Wei YanMin,Jin Meilin,Zhang Anding
Streptococcus suis (S. suis) ranks among the five most important porcine pathogens worldwide and occasionally threatens human health, especially in people that come into close contact with pigs or pork products. Streptococcus suis serotype 2 (SS2) is considered to be the most pathogenic and prevalent capsular type. As a first line of immune defense against SS2 infection, neutrophils can eliminate the invader not only by phagocytosis but also by neutrophil extracellular traps (NETs)-mediated killing. SS2 can resist phagocytosis through polysaccharide capsule (CPS), but how this strain evades the effects of NETs remains to be determined. The present study demonstrated that the epidemic strain 05ZY, the highly pathogenic strain P1/7 and the intermediately pathogenic strain A7 could induce the formation of NETs. Furthermore, SS2 strains could successfully resist NETs-mediated killing, and the CPS structure contributed to this resistance by escaping the trapping. Therefore, the CPS structure not only contributed to the SS2 strains’ resistance to phagocytosis-mediated killing but also played an essential role in evading NETs trapping and further killing in vitro. This study strengthens our understanding of how S. suis can evade innate immune surveillance and elimination.
研究领域:
微生物学
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免疫学
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DOI
PubMed
高影响因子
Frontiers in Veterinary Science
·
2022
·
IF 3.471
Lu Yixing,Yang Liuye,Zhang Wanying,Li Jie,Peng Xianfeng,Qin Zonghua,Zeng Zhenling,Zeng Dongping
This study aimed to evaluate the antibacterial activity of isopropoxy benzene guanidine (IBG) against C. perfringens based on pharmacokinetics/pharmacodynamics (PK/PD) modeling in broilers. The PK parameters of IBG in the plasma and ileal content of C. perfringens-infected broilers following oral administration at 2, 30, and 60 mg/kg body weight were investigated. in vivo PD studies were conducted over oral administration ranging from 2 to 60 mg/kg and repeated every 12 h for 3 days. The inhibitory Imax model was used for PK/PD modeling. Results showed that the MIC of IBG against C. perfringens was 0.5–32 mg/L. After oral administration of IBG, the peak concentration (Cmax), maximum concentration time (Tmax), and area under the concentration-time curve (AUC) in ileal content of broilers were 10.97–1,036.64 mg/L, 2.39–4.27 h, and 38.31–4,266.77 mg·h/L, respectively. After integrating the PK and PD data, the AUC0 − 24h/MIC ratios needed for the bacteriostasis, bactericidal activity, and bacterial eradication were 4.00, 240.74, and 476.98 h, respectively. For dosage calculation, a dosage regimen of 12.98 mg/kg repeated every 12 h for 3 days was be therapeutically effective in broilers against C. perfringens with MIC ≤ 2 mg/L. In addition, IBG showed potent activity against C. perfringens, which may be responsible for cell membrane destruction. These results can facilitate the evaluation of the use of IBG in the treatment of intestinal diseases in broilers caused by C. perfringens.
研究领域:
兽医学
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微生物学
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药理学
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DOI
PubMed
高影响因子
Science Advances
·
2023
·Vol. 9
·期 7
·
IF 13.6
Yu-Jia Wang,Lian Li,Jie Yu,Hong-Yu Hu,Zi-Xu Liu,Wen-Jie Jiang,Wei Xu,Xue-Ping Guo,Feng-Shan Wang,Ju-Zheng Sheng
The introduction of unnatural chemical moieties into glycosaminoglycans (GAGs) has enormous potential to facilitate studies of the mechanism and application of these critical, widespread molecules. Unnatural N-acetylhexosamine analogs were metabolically incorporated into the capsule polysaccharides of Escherichia coli and Bacillus subtilis via bacterial metabolism. Targeted metabolic labeled hyaluronan and the precursors of heparin and chondroitin sulfate were obtained. The azido-labeled polysaccharides (purified or in capsules) were reacted with dyes, via bioorthogonal chemistry, to enable detection and imaging. Site-specific introduction of fluorophores directly onto cell surfaces affords another choice for observing and quantifying bacteria in vivo and in vitro. Furthermore, azido-polysaccharides retain similar biological properties to their natural analogs, and reliable and predictable introduction of functionalities, such as fluorophores, onto azido-N-hexosamines in the disaccharide repeat units provides chemical tools for imaging and metabolic analysis of GAGs in vivo and in vitro.
研究领域:
微生物学
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生物化学
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分子生物学
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化学生物学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
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IF 8.5
Wenzhuo Wang,Wei Yuan,Tingting Lin,Zhilan Sun,Fei Liu,Daoying Wang,Fang Liu
A three-mode biosensor incorporated ratiometric (electrochemical/colorimetric, electrochemical/photothermal) into its design was constructed using DNA-driven magnetic beads (DMBs) as a bridge to detect C. perfringens. It further enhances the accuracy of detection results while maintaining compatibility with applications in multiple scenarios. Briefly, the G-quadruplex was combined with aptamer and immobilized onto magnetic beads through amide-bond, resulting in the integration of DMBs. The DMBs and supernatant were separated by magnetic separation when the target was present. Subsequently, the DMBs were utilized to construct the electrochemical biosensor, whereas the supernatant was used to construct colorimetric and photothermal biosensors. The limits of detection the ratiometric biosensor were ultimately reduced to 0.26 and 0.27 lg CFU g −1 , respectively, in comparison to the single three-mode biosensor. Moreover, this biosensor had been applied in real-sample assays successfully. The establishment of this platform provides a new method for detecting pathogens in the fields of food safety and environmental monitoring.
研究领域:
食品安全
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环境监测
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生物传感技术
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产品关联
DOI
PubMed
高影响因子
Frontiers in Cellular and Infection Microbiology
·
2025
·
IF 4.8
Yufeng Dai,Qiang Zhao,Huanhuan Yan,Kun Ye,Lifeng Wang,Ling Guo,Na Guo,Wenwen Li,Jiyong Yang
Introduction: The impact of the hypermucoviscosity (HMV) phenotype in ST11-KL47 carbapenem-resistant Klebsiella pneumoniae (CRKp) pathogenicity warrants investigation for public health risk assessment.Methods: We analyzed 230 clinical ST11-KL47 CRKp to identify the key factor in mucoviscosity acquisition via comparative genomic analysis. Sedimentation value served as the objective index to quantify HMV. The virulence in vivo was assessed using Galleria mellonella and mouse infection models. We employed genome engineering, capsular polysaccharides (CPS) quantification, and visualization to explore the role of Wzc mutation in CPS biosynthesis and HMV. The biological impact of Wzc-mediated HMV was investigated through competitive growth analysis, biofilm formation, serum resistance, anti-phagocytic ability, and adhesion assays. Transcriptomic analysis and scanning electron microscopy (SEM) were utilized to explore the relationship between polysaccharide composition, physical distribution, and changes in virulence.Results: The Wzc mutations are identified as the key to mucoviscosity acquisition. Unexpectedly, Wzc-mediated HMV CRKp exhibits reduced pathogenicity versus non-mucoviscosity (NMV) strains in different animal models, with competitive disadvantage, decreased biofilm formation, serum resistance, and adhesion, yet higher anti-phagocytic ability in vitro. CPS extraction and visualization of genome-engineered strains verify the Wzc mutations mediate HMV by standardizing CPS chain length and overproducing cell-free extracellular polysaccharides (cell-free EPS). Transcriptomic results, lipopolysaccharides (LPS) quantification, and SEM collectively indicate a downregulation of LPS synthesis and the masking of LPS in HMV strains.Discussion: These findings demonstrate that the Wzc-induced HMV attenuates ST11-KL47 CRKp virulence by modifying the exopolysaccharide composition and physical distribution.
研究领域:
微生物学
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基因组学
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传染病学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Biology-Basel
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2025
·Vol. 14
·期 8
·986
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IF 3.5
Yanjian Yang,Guanrong Zhang,Ruilong Xu,Yiyang Deng,Zequan Mo,Yanwei Li,Xueming Dan
Simple SummaryStreptococcus iniae(S. iniae) is a major aquaculture pathogen causing significant economic losses. While infections show seasonal patterns tied to water temperature, the mechanisms behind its thermal adaptation remain unclear. This study explored the proteomic changes inS. iniaeat different temperatures and their effects on immune responses in yellowfin seabream (Acanthopagrus latus,A. latus). Results demonstrated that elevated temperatures markedly upregulated bacterial virulence factor expression, resulting in significantly higher host mortality rates. Furthermore, thermal stress enhances the destruction of key immune functions of the host byS. iniae, including immune cell survival, ROS production, and phagocytic activity. These findings provide novel insights into the heat-regulated immune evasion strategies ofS. iniae, offering valuable theoretical foundations for developing temperature-aware disease management protocols in aquaculture systems.Streptococcus iniae(S. iniae) is a globally significant aquatic pathogen responsible for severe economic losses in aquaculture. While theS. iniaeinfection often exhibits distinct seasonal patterns strongly correlated with water temperature, there is limited knowledge regarding the temperature-dependent immune evasion strategies ofS. iniae. Our results demonstrated a striking temperature-dependent virulence phenotype, with significantly higherA. latusmortality rates observed at high temperature (HT, 33 °C) compared to low temperature (LT, 23 °C). Proteomic analysis revealed temperature-dependent upregulation of key virulence factors, including streptolysin S-related proteins (SagG, SagH), antioxidant-related proteins (SodA), and multiple capsular polysaccharide (cps) synthesis proteins (cpsD, cpsH, cpsL, cpsY). Flow cytometry analysis showed that HT infection significantly reduced the percentage of lymphocyte and myeloid cell populations in the head kidney leukocytes ofA. latus, which was associated with elevatedcaspase-3/7expression and increased apoptosis. In addition, HT infection significantly inhibited the release of reactive oxygen species (ROS) but not nitric oxide (NO) production. UsingS. iniaecps-deficient mutant, Δcps, we demonstrated that the cps is essential for temperature-dependent phagocytosis resistance inS. iniae, as phagocytic activity against Δcps remained unchanged across temperatures, while NS-1 showed significantly reduced uptake at HT. These findings provide new insights into the immune evasion ofS. iniaeunder thermal regulation, deepening our understanding of the thermal adaptation of aquatic bacterial pathogens.
研究领域:
微生物学
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鱼类免疫学
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分子病理学
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水产养殖疾病防控
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宿主-病原体相互作用
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环境微生物适应
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蛋白质组学
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先天免疫
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PLoS Pathogens
·
2024
·Vol. 20
·期 10
·e1012675
·
IF 5.5
Lijun Wang,Zhe Wang,Hua Zhang,Qian Jin,Shuaihua Fan,Yanni Liu,Xueting Huang,Jun Guo,Chao Cai,Jing-ren Zhang,Hui Wu
Klebsiella pneumoniae , an emerging multidrug-resistant pathogen, exhibits hypermucoviscosity (HMV) as a critical virulence trait mediated by its capsular polysaccharide (CPS). Recent discoveries have determined acetylation as a significant modification for CPS, although its impact on HMV and virulence was previously unknown. This study elucidates the roles of two enzymes: K lebsiella p neumoniae A cetylated C PS E sterase (KpACE), an esterase that removes acetyl groups from CPS, and WcsU, an acetyltransferase that adds acetyl groups to CPS. KpACE is highly upregulated in an ompR -deficient mutant lacking HMV, and its overexpression consistently reduces HMV and diminishes virulence in a mouse model of pneumonia. The esterase domain-containing KpACE effectively deacetylates model sugar substrates and CPS-K2. Site-directed mutagenesis of the conserved catalytic histidine residue at position 370 significantly reduces its enzymatic activity. This reduction correlates with decreased HMV, affecting key virulence traits including biofilm formation and serum resistance. Similarly, a deficiency in the wcsU gene abolishes CPS acetylation, and reduces HMV and virulence. These results highlight the importance of the delicate balance between CPS acetylation by WcsU and deacetylation by KpACE in regulating the pathogenicity of K . pneumoniae . Understanding this balance provides new insights into the modulation of virulence traits and potential therapeutic targets for combating K . pneumoniae infections.
Klebsiella pneumoniae is an antibiotic-resistant pathogen known for its virulence factor, hypermucoviscosity (HMV), which relies on the production of capsular polysaccharides (CPS). This study highlights the roles of two key enzymes: KpACE, an esterase that removes acetyl groups from CPS, and WcsU, an acetyltransferase that adds acetyl groups to CPS. Overexpression of KpACE reduces HMV and decreases virulence in a mouse pneumonia model by deacetylating CPS. Conversely, a deficiency in the wcsU gene, which is responsible for acetylating CPS, also results in decreased HMV and virulence. The balance between CPS acetylation by WcsU and deacetylation by KpACE is crucial in regulating K . pneumoniae pathogenicity. This balance affects various virulence factors, including biofilm formation and serum resistance, highlighting the importance of CPS acetylation dynamics in the pathogen’s fitness and virulence. Understanding these mechanisms offers insights into potential therapeutic targets to mitigate the virulence and antibiotic resistance of K . pneumoniae .
研究领域:
微生物学
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传染病学
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分子生物学
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致病机制
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产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2023
·
IF 5.2
Tang Miran,Huang Zeyu,Zhang Xiaodong,Kong Jingchun,Zhou Beibei,Han Yijia,Zhang Yi,Chen Lijiang,Zhou Tieli
Introduction: Phage is promising for the treatment of hypervirulent Klebsiella pneumoniae (hvKP) infections. Although phage resistance seems inevitable, we found that there still was optimization space in phage therapy for hvKP infection.Methods: The clinical isolate K. pneumoniae FK1979 was used to recover the lysis phage ΦFK1979 from hospital sewage. Phage-resistant bacteria were obtained on LB agar and used to isolate phages from sewage. The plaque assay, transmission electron microscopy (TEM), multiplicity of infection test, one-step growth curve assay, and genome analysis were performed to characterize the phages. Colony morphology, precipitation test and scanning electron microscope were used to characterize the bacteria. The absorption test, spot test and efficiency of plating (EOP) assay were used to identify the sensitivity of bacteria to phages. Whole genome sequencing (WGS) was used to identify gene mutations of phage-resistant bacteria. The gene expression levels were detected by RT-qPCR. Genes knockout and complementation of the mutant genes were performed. The change of capsules was detected by capsule quantification and TEM. The growth kinetics, serum resistance, biofilm formation, adhesion and invasion to A549 and RAW 264.7 cells, as well as G. mellonella and mice infection models, were used to evaluate the fitness and virulence of bacteria.Results and discussion: Here, we demonstrated that K2 capsule type sequence type 86 hvKP FK1979, one of the main pandemic lineages of hvKP with thick capsule, rapidly developed resistance to a K2-specific lysis phage ΦFK1979 which was well-studied in this work to possess polysaccharide depolymerase. The phage-resistant mutants showed a marked decrease in capsule expression. WGS revealed single nucleotide polymorphism (SNP) in genes encoding RfaH, galU, sugar glycosyltransferase, and polysaccharide deacetylase family protein in the mutants. RfaH and galU were further identified as being required for capsule production and phage sensitivity. Expressions of genes involved in the biosynthesis or regulation of capsule and/or lipopolysaccharide significantly decreased in the mutants. Despite the rapid and frequent development of phage resistance being a disadvantage, the attenuation of virulence and fitness in vitro and in vivo indicated that phage-resistant mutants of hvKP were more susceptible to the immunity system. Interestingly, the newly isolated phages targeting mutants changed significantly in their plaque and virus particle morphology. Their genomes were much larger than and significantly different from that of ΦFK1979. They possessed much more functional proteins and strikingly broader host spectrums than ΦFK1979. Our study suggests that K2-specific phage has the potential to function as an antivirulence agent, or a part of phage cocktails combined with phages targeting phage-resistant bacteria, against hvKP-relevant infections.
研究领域:
微生物学
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分子生物学
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传染病学
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基因组学
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噬菌体疗法
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产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2021
·
IF 5.64
Wang Wenbin,Liu Jianxin,Guo Shanshan,Liu Lei,Yuan Qianyun,Guo Lei,Pan Saikun
The discovery of outer membrane proteins (OMPs) with desirable specificity and surface availability is a fundamental challenge to develop accurate immunodiagnostic assay and multivalent vaccine of pathogenic Vibrio species in food and aquaculture. Herein 101 OMPs were systemically screened from 4,831 non-redundant proteins of Vibrio parahaemolyticus by bioinformatical predication of signaling peptides, transmembrane (TM) α-helix, and subcellular location. The sequence homology analysis with 32 species of Vibrio spp. and all the non-Vibrio strains revealed that 15 OMPs were conserved in at least 23 Vibrio species, including BamA (VP2310), GspD (VP0133), Tolc (VP0425), OmpK (VP2362), OmpW (VPA0096), LptD (VP0339), Pal (VP1061), flagellar L-ring protein (VP0782), flagellar protein MotY (VP2111), hypothetical protein (VP1713), fimbrial assembly protein (VP2746), VacJ lipoprotein (VP2214), agglutination protein (VP1634), and lipoprotein (VP1267), Chitobiase (VP0755); high adhesion probability of flgH, LptD, OmpK, and OmpW indicated they were potential multivalent Vibrio vaccine candidates. V. parahaemolyticus OMPs were found to share high homology with at least one or two Vibrio species, 19 OMPs including OmpA like protein (VPA073), CsuD (VPA1504), and MtrC (VP1220) were found relatively specific to V. parahaemolyticus. The surface proteomic study by enzymatical shaving the cells showed the capsular polysaccharides most likely limited the protease action, while the glycosidases improved the availability of OMPs to trypsin. The OmpA (VPA1186, VPA0248, VP0764), Omp (VPA0166), OmpU (VP2467), BamA (VP2310), TolC (VP0425), GspD (VP0133), OmpK (VP2362), lpp (VPA1469), Pal (VP1061), agglutination protein (VP1634), and putative iron (III) compound receptor (VPA1435) have better availability on the cell surface.
研究领域:
微生物学
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分子生物学
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免疫学
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生物信息学
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食品科学
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水产养殖
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED MICROBIOLOGY
·
2020
·Vol. 128
·期 6
·1764-1775
·
IF 3.066
Zheng L.,Hu Y.,He X.,Zhao Y.,Xu H.
AimsThe purpose of this study was to isolate Lactobacillus from gastrointestinal tract of healthy postweaning piglets and investigate its synergistic antimicrobial and probiotic effects with ZnO nanoparticles (nZnO).Methods and ResultsOf the 128 isolates, Lactobacillus plantarum BLPL03 was selected based on its excellent acid and bile salt tolerance properties. Lactobacillus plantarum BLPL03 was sensitive to β‐lactams, macrolides, amphenicols and cephalosporins, whereas it displayed the steady resistance to aminoglycosides, tetracyclines, quinolones and peptide antibiotics. In vitro analysis of antibacterial activities showed that L. plantarum BLPL03 inhibited the four common food‐borne pathogenic bacteria including Escherichia coli O157:H7 CMCC 44828, Salmonella Typhimurium ATCC 13311, Staphylococcus aureus CMCC 26003 and Listeria monocytogenes CMCC 54007 in synergy with nZnO. Furthermore, the quantitative polymerase chain reaction test demonstrated that the combined administration of L. plantarum BLPL03 fermentation liquor (LFL) and nZnO synergistically elevated the faecal number of Bifidobacterium by 73·19‐fold, and reduced the two potential enteropathogenic bacteria Enterobacteriaceae and Clostridium perfringens in mice challenged with Salm. Typhimurium. Finally, dietary supplementation with low dose of nZnO (20 mg kg−1) when combined with LFL administration enhanced final body weight, fur appearance and average daily gain, and decreased feed conversion ratio and diarrhoea incidence in weaned piglets. The faecal Bifidobacterium and Lactobacillus of piglets were dramatically enhanced by 81·96‐ and 3·15‐fold, respectively, after administration of a mixture of nZnO and LFL. Meanwhile, combination of nZnO with LFL resulted in low levels of Bacteroides, Enterococcus, and Enterobacteriaceae.ConclusionsA combination of nZnO and LFL exhibits potential health‐benefit properties for the control of gut microbial composition by their synergistic antimicrobial and probiotic effects.Significance and Impact of the StudyThis study may provide a potential nutritional strategy to improve performance and gut health of animals with gut microbiota disorders caused by pathogen infections and weanling, and so on.
研究领域:
微生物学
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动物科学
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营养学
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兽医学
✓ 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）