JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2023
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IF 3
Guorong Ma,Pengzheng Luo,Ruiqiang Xu,Rui Ma,Lei Qiu,Chenran Xu,Rang Yang,Yating Li,Zhihao Zhao,Ling Huang,Yanhui Yang,Pei Wang
M. tuberculosis is the most successful intracellular pathogen and remains a major threat to human health. It is crucial to investigate the profile of cytoplasmic proteins from M. tuberculosis for pathogenesis, clinical markers, and protein vaccine development. In this study, six biomimetic affinity chromatography (BiAC) resins with high differences were selected for M. tuberculosis- cytoplasmic protein fractionation. All fractions were identified using liquid chromatography-mass spectrometry (LC-MS/MS) analysis. A total of 1246 M. tuberculosis proteins were detected (p < 0.05), among which 1092 M. tuberculosis proteins were identified in BiAC fractionations and 714 M. tuberculosis proteins in un-fractionations (Table S1.3.1). The majority of 66.8% (831/1246) identifications were distributed in the range of Mw 7.0–70.0 kDa, pI 3.5–8.0, and Gravy values <0.3. Furthermore, 560 M. tuberculosis proteins were detected in both the BiAC fractionations and un-fractionations. Compared with the un-fractionations, the average number of prot_matches, prot_cover, prot_sequence, and emPAI values of these 560 proteins in the BiAC fractionations were increased by 3.791, 1.420, 1.307, and 1.788 times, respectively. Overall, compared with un-fractionations, the confidence and profile of M. tuberculosis cytoplasmic proteins were improved by BiAC fractionations coupled with LC-MS/MS analysis. The strategy of BiAC fractionation can be used as an effective method for pre-separating protein mixtures in proteomic studies.
研究领域:
微生物学
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蛋白质组学
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生物信息学
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传染病学
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DOI
PubMed
高影响因子
BMC Veterinary Research
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2022
·Vol. 18
·期 1
·1-14
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IF 2.792
Hao Fei,Xie Xing,Feng Zhixin,Chen Rong,Wei Yanna,Liu Jin,Xiong Qiyan,Shao Guoqing,Lin Johnson
Background Mycoplasma hyopneumoniae (M. hyopneumoniae) is the etiological agent of enzootic pneumonia, a highly infectious swine respiratory disease that distributed worldwide. The pathogenesis and virulence factors of M. hyopneumoniae are not fully clarified. As an important virulence factor of bacteria, nicotinamide adenine dinucleotide (NADH) oxidase (NOX) participates in host-pathogen interaction, however, the function of NOX involved in the pathogenesis of M. hyopneumoniae is not clear.Results In this study, significant differences in NOX transcription expression levels among different strains of M. hyopneumoniae differed in virulence were identified, suggesting that NOX may be correlated with M. hyopneumoniae virulence. The nox gene of M. hyopneumoniae was cloned and expressed in Escherichia coli, and polyclonal antibodies against recombinant NOX (rNOX) were prepared. We confirmed the enzymatic activity of rNOX based on its capacity to oxidize NADH to NAD+. Flow cytometry analysis demonstrated the surface localization of NOX, and subcellular localization analysis further demonstrated that NOX exists in both the cytoplasm and cell membrane. rNOX was depicted to mediate adhesion to immortalized porcine bronchial epithelial cells (hTERT-PBECs). Pre-neutralizing M. hyopneumoniae with anti-rNOX antibody resulted in a more than 55% reduction in the adhesion rate of high- and low-virulence M. hyopneumoniae strains to hTERT-PBECs. Moreover, a significant difference appeared in the decline in CCU50 titer between virulent (168) and virulence-attenuated (168L) strains. NOX not only recognized and interacted with host fibronectin but also induced cellular oxidative stress and apoptosis in hTERT-PBECs. The release of lactate dehydrogenase by NOX in hTERT-PBECs was positively correlated with the virulence of M. hyopneumoniae strains.Conclusion sNOX is considered to be a potential virulence factor of M. hyopneumoniae and may play a significant role in mediating its pathogenesis.
研究领域:
微生物学
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兽医学
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分子生物学
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病理学
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PubMed
高影响因子
PLoS Pathogens
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2024
·Vol. 20
·期 10
·e1012675
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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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PubMed
高影响因子
Scientific Reports
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2017
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IF 4.259
Wanyan Deng,Quanxin Long,Jie Zeng,Ping Li,Wenmin Yang,Xinchun Chen,Jianping Xie
The success of Mycobacterium tuberculosis (M. tuberculosis) as a pathogen is largely contributes to its ability to manipulate the host immune responses. The genome of M. tuberculosis encodes multiple immune-modulatory proteins, including several members of the multi-genic PE_PPE family. Despite of intense research, the roles of PE_PGRS proteins in mycobacterial pathogenesis remain elusive. The function of M. tuberculosis PE_PGRS41, characterized by an extended and unique C-terminal domain, was studied. Expression of PE_PGRS41 in Mycobacterium smegmatis, a non-pathogenic species intrinsically deficient of PE_PGRS, severely impaired the resistance of the recombinant to multiple stresses via altering the cell wall integrity. Macrophages infected by M. smegmatis harboring PE_PGRS41 decreased the production of TNF-α, IL-1β and IL-6. In addition, PE_PGRS41 boosted the survival of M. smegmatis within macrophage accompanied with enhanced cytotoxic cell death through inhibiting the cell apoptosis and autophagy. Taken together, these results implicate that PE_PGRS41 is a virulence factor of M. tuberculosis and sufficient to confer pathogenic properties to M. smegmatis.
研究领域:
微生物学
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免疫学
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致病机制
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细胞生物学
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高影响因子
Frontiers in Immunology
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2022
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IF 8.786
Zhang Nan,Gao Xiaochen,Zhang Weijia,Xiong Junyao,Cao Xiaojian,Fu Zhen F.,Cui Min
Japanese encephalitis virus (JEV) is one of the most important members of the flavivirus family. It is a typical zoonotic pathogen that has caused substantial social and economic losses worldwide. The relation between JEV-induced immunosuppression and inflammatory responses has not been thoroughly investigated. In this study, cells infiltrating the brain tissue of JEV-infected mice were mainly identified as monocytic myeloid-derived suppressor cells (M-MDSCs), which subsequently differentiated into CD3+ macrophages. Co-culture with T cells showed that both splenic M-MDSCs and brain infiltrated M-MDSCs isolated from JEV-infected mice inhibited T cell proliferation through ARG1 and iNOS. The splenectomy model revealed that JEV-induced M-MDSCs were mainly derived from bone marrow and migrated to the spleen and central nervous system (CNS). The results of the transcriptome analysis and IRF7-deficient mice indicated that the ZBP1-IRF7 signaling pathway stimulated by JEV RNA played a central role in the induction of M-MDSCs. M-MDSCs migrated into the CNS through the chemokine CCL2/N-CCL2 derived from astrocytes and brain infiltrated M-MDSCs differentiated into CD3+ macrophages through a mechanism mediated by M-CSF, IL-6 and IFN-γ in the brain microenvironment. These findings provide evidence for the mechanism that JEV regulates the differentiation of M-MDSCs and thereby exacerbates pathogenicity, which represents a potential therapeutic target for Japanese encephalitis (JE).
研究领域:
免疫学
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神经病毒学
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病毒学
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致病机制
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产品关联
DOI
PubMed
高影响因子