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BACKGROUND: To establish a chemiluminescence method for detecting anti-E1 and anti-E2 antibodies in the serum of patients with hepatitis C virus (HCV) infection. METHODS: The microplate was coated with recombinant envelope proteins E1 and E2 by indirect method, respectively, and the kits for detecting anti-E1 and anti-E2 antibodies were prepared. The methodological indexes were evaluated. RESULTS: The methodological indexes of the kits were as follows: precision test (the variation coefficient of anti-E1 antibody 6.71%-8.95% for within run and 9.91%-12.16% for between run, the variation coefficient of anti-E2 antibody 6.06%-8.44% for within run and 10.77%-13.98% for between run, respectively). The blank limit and detection limit were 1.18 RLIR and 3.16 RLIR for the anti-E1 antibody, and 1.26 RLIR and 3.32 RLIR for the anti-E2 antibody, respectively. The correlation coefficients (r) of anti-E1 and anti-E2 were 0.9963 and 0.9828, the analysis and measurement ranges (AMR) were 1.66-41.28 RLIR and 1.55-19.46 RLIR, and the average recovery was 96.4% and 93.7%, respectively. The rheumatoid factor and other positive serum samples had no interference or cross-reaction to the test, and the kits were stable within 15 months. The positive rates of anti-E1 and anti-E2 antibodies in 45 patients with HCV infection were 35.6% (16/45) and 44.4% (20/45), respectively. CONCLUSIONS: The kits for detecting anti-E1 and anti-E2 meet the requirements of methodology, and can be used in screening diagnosis, disease monitoring, prognosis evaluation, disease mechanism, and epidemiological studies of HCV infection. The HCV envelope proteins E1 and E2 have an immune response in HCV-infected patients.
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Hepacivirus , Hepatite C , Humanos , Luminescência , Anticorpos Anti-Hepatite C , Anticorpos , Proteínas Recombinantes , Proteínas do Envelope ViralRESUMO
Although the pre-clinical study of chimeric antigen receptor (CAR)-natural killer (NK) cell was effective against various tumours, immunosuppression mediated by tumour microenvironment hampers their application and several efforts have been explored to improve their effect in combating solid tumours. Glypican 3 (GPC3) is a promising target for hepatocellular carcinoma (HCC), and CAR-T cells targeting GPC3 have been tested in clinical trials. Based on an affinity-enhanced antibody (hYP7) targeting GPC3, we constructed GPC3-CAR-NK cells to explore their potential function in the treatment of HCC. We found that patients with HCC secreted high levels of soluble programmed death-ligand 1 (sPD-L1), which inhibits the function of CAR-NK cells targeting GPC3. In addition, we combined high-affinity sPD-L1 variant (L3C7c-Fc) with GPC3-CAR-NK cells to solve the problem of GPC3-CAR-NK inhibition. Our studies demonstrated that L3C7c-Fc could enhance the therapeutic effect of CAR-NK cells by reversing the suppression of sPD-L1, which provides the experimental evidence for the subsequent development of HCC immunotherapy strategies.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Glipicanas/genética , Células Matadoras Naturais , Microambiente TumoralRESUMO
Prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) has compromised antimicrobial efficacy against severe infections worldwide. To monitor global spread, we conducted a comprehensive genomic epidemiologic study comparing sequences from 21 blaOXA-232-carrying CRKP isolates from China with K. pneumoniae sequence type (ST) 15 strains from 68 countries available in GenBank. Phylogenetic and phylogeographic analyses revealed all blaOXA-232-carrying CRKP isolates belonged to ST15 lineage and exhibited multidrug resistance. Analysis grouped 330 global blaOXA-232-carrying ST15 CRKP strains into 5 clades, indicating clonal transmission with small genetic distances among multiple strains. The lineage originated in the United States, then spread to Europe, Asia, Oceania, and Africa. Most recent common ancestor was traced back to 2000; mutations averaged ≈1.7 per year per genome. Our research helps identify key forces driving global spread of blaOXA-232-carrying CRKP ST15 lineage and emphasizes the importance of ongoing surveillance of epidemic CRKP.
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Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Humanos , Carbapenêmicos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Klebsiella pneumoniae , Filogeografia , Plasmídeos , Filogenia , Genômica , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico , beta-Lactamases/genética , Testes de Sensibilidade MicrobianaRESUMO
AIMS: His-Purkinje system pacing has been demonstrated as a synchronized ventricular pacing strategy via pacing His-Purkinje system directly, which can decrease the incidence of adverse cardiac structure alteration compared with right ventricular pacing (RVP). The purpose of this meta-analysis was to compare the effects of His-Purkinje system pacing and RVP in patients with bradycardia and cardiac conduction dysfunction. METHODS: PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from the establishment of databases up to 15 December 2019. Studies on long-term clinical outcomes of His-Purkinje system pacing and RVP were included. Chronic paced QRS duration, chronic pacing threshold, left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), all-cause mortality, and heart failure hospitalization were collected for meta-analysis. RESULTS: A total of 13 studies comprising 2348 patients were included in this meta-analysis. Compared with RVP group, patients receiving His-Purkinje system pacing showed improvement of LVEF (mean difference [MD], 5.65; 95% confidence interval [CI], 4.38-6.92), shorter chronic paced QRS duration (MD, - 39.29; 95% CI, - 41.90 to - 36.68), higher pacing threshold (MD, 0.8; 95% CI, 0.71-0.89) and lower risk of heart failure hospitalization (odds ratio [OR], 0.65; 95% CI, 0.44-0.96) during the follow-up. However, no statistical difference existed in LVEDV, LVESV and all-cause mortality between the two groups. CONCLUSION: Our meta-analysis suggests that His-bundle pacing is more suitable for the treatment of patients with bradycardia and cardiac conduction dysfunction.
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Bradicardia/terapia , Fascículo Atrioventricular/fisiopatologia , Doença do Sistema de Condução Cardíaco/terapia , Estimulação Cardíaca Artificial , Frequência Cardíaca , Ramos Subendocárdicos/fisiopatologia , Potenciais de Ação , Idoso , Bradicardia/diagnóstico , Bradicardia/mortalidade , Bradicardia/fisiopatologia , Doença do Sistema de Condução Cardíaco/diagnóstico , Doença do Sistema de Condução Cardíaco/mortalidade , Doença do Sistema de Condução Cardíaco/fisiopatologia , Estimulação Cardíaca Artificial/efeitos adversos , Estimulação Cardíaca Artificial/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Fatores de Tempo , Função Ventricular Esquerda , Função Ventricular DireitaRESUMO
The twitching motility of bacteria is closely related to environmental adaptability and pathogenic behaviors. Lysobacter is a good genus in which to study twitching motility because of the complex social activities and distinct movement patterns of its members. Regardless, the mechanism that induces twitching motility is largely unknown. In this study, we found that the interspecies signal indole caused Lysobacter to have irregular, random twitching motility with significantly enhanced speed. Deletion of qseC or qseB from the two-component system for indole signaling perception resulted in the disappearance of rapid, random movements and significantly decreased twitching activity. Indole-induced, rapid, random twitching was achieved through upregulation of expression of gene cluster pilE1-pilY11-pilX1-pilW1-pilV1-fimT1 In addition, under conditions of extremely low bacterial density, individual Lysobacter cells grew and divided in a stable manner in situ without any movement. The intraspecies quorum-sensing signaling factor 13-methyltetradecanoic acid, designated L. enzymogenes diffusible signaling factor (LeDSF), was essential for Lysobacter to produce twitching motility through indirect regulation of gene clusters pilM-pilN-pilO-pilP-pilQ and pilS1-pilR-pilA-pilB-pilC These results demonstrate that the motility of Lysobacter is induced and regulated by indole and LeDSF, which reveals a novel theory for future studies of the mechanisms of bacterial twitching activities.IMPORTANCE The mechanism underlying bacterial twitching motility is an important research area because it is closely related to social and pathogenic behaviors. The mechanism mediating cell-to-cell perception of twitching motility is largely unknown. Using Lysobacter as a model, we found in this study that the interspecies signal indole caused Lysobacter to exhibit irregular, random twitching motility via activation of gene cluster pilE1-pilY11-pilX1-pilW1-pilV1-fimT1 In addition, population-dependent behavior induced by 13-methyltetradecanoic acid, a quorum-sensing signaling molecule designated LeDSF, was involved in twitching motility by indirectly regulating gene clusters pilM-pilN-pilO-pilP-pilQ and pilS1-pilR-pilA-pilB-pilC The results demonstrate that the twitching motility of Lysobacter is regulated by these two signaling molecules, offering novel clues for exploring the mechanisms of twitching motility and population-dependent behaviors of bacteria.
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Indóis/metabolismo , Lysobacter/fisiologia , Família Multigênica , Transdução de Sinais , Regulação para Cima , Genes Bacterianos , Percepção de QuorumRESUMO
MomL is a marine-derived quorum-quenching (QQ) lactonase which can degrade various N-acyl homoserine lactones (AHLs). Intentional modification of MomL may lead to a highly efficient QQ enzyme with broad application potential. In this study, we used a rapid and efficient method combining error-prone polymerase chain reaction (epPCR), high-throughput screening and site-directed mutagenesis to identify highly active MomL mutants. In this way, we obtained two candidate mutants, MomLI144V and MomLV149A. These two mutants exhibited enhanced activities and blocked the production of pathogenic factors of Pectobacterium carotovorum subsp. carotovorum (Pcc). Besides, seven amino acids which are vital for MomL enzyme activity were identified. Substitutions of these amino acids (E238G/K205E/L254R) in MomL led to almost complete loss of its QQ activity. We then tested the effect of MomL and its mutants on Pcc-infected Chinese cabbage. The results indicated that MomL and its mutants (MomLL254R, MomLI144V, MomLV149A) significantly decreased the pathogenicity of Pcc. This study provides an efficient method for QQ enzyme modification and gives us new clues for further investigation on the catalytic mechanism of QQ lactonase.
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Aminoácidos/análise , Hidrolases de Éster Carboxílico , Pectobacterium carotovorum/enzimologia , Pectobacterium carotovorum/genética , Engenharia de Proteínas , Substituição de Aminoácidos , Brassica rapa/microbiologia , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Ativação Enzimática/genética , Mutação , Pectobacterium carotovorum/patogenicidade , Virulência/genéticaRESUMO
Colorectal cancer is one of the most common malignant tumors in humans, with liver metastasis being the primary cause of mortality. The epithelial-mesenchymal transition (EMT) process endows cancer cells with enhanced metastatic potential. To elucidate the cellular mechanisms driving EMT in colorectal cancer, we analyzed single-cell RNA sequencing data from 11 nonmetastatic primary tumors (TnM) and 11 metastatic primary tumors (TM) from colorectal cancer patients. Compared with the TnM group, the TM samples showed elevated numbers of malignant epithelial cell and cancer-associated fibroblast (CAF) subsets that displayed enrichments of EMT, angiogenesis, and TGFß signaling pathways. One specific TM-enriched subgroup of malignant epithelial cells underwent EMT to transdifferentiate into CXCL1+ CAFs that subsequently differentiated into SFRP2+ CAFs, which was validated by spatial transcriptomic and pseudotime trajectory analyses. Furthermore, cell-cell communication analysis identified BHLHE40 as a probable key transcription factor driving EMT that was associated with poor prognosis. Finally, in vitro and in vivo experiments functionally substantiated that BHLHE40 promoted the proliferation, invasion, migration, EMT, and liver metastasis of colorectal cancer cells. In summary, this study identified BHLHE40 as a key transcription factor regulating EMT that promotes liver metastasis in colorectal cancer. Significance: Integrated analysis of single-cell RNA sequencing and spatial transcriptomics in metastatic colorectal cancer provides insights into the mechanisms underlying EMT and cancer-associated fibroblast differentiation, which could help improve patient diagnosis and treatment.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos , Fibroblastos Associados a Câncer , Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Neoplasias Hepáticas , Animais , Feminino , Humanos , Masculino , Camundongos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Camundongos Nus , Prognóstico , Análise de Célula Única/métodos , TranscriptomaRESUMO
Excessive fructose diet is closely associated with colorectal cancer (CRC) progression. Nevertheless, fructose's specific function and precise mechanism in colorectal cancer liver metastasis (CRLM) is rarely known. Here, this study reported that the fructose absorbed by primary colorectal cancer could accelerate CRLM, and the expression of KHK-A, not KHK-C, in liver metastasis was higher than in paired primary tumors. Furthermore, KHK-A facilitated fructose-dependent CRLM in vitro and in vivo by phosphorylating PKM2 at Ser37. PKM2 phosphorylated by KHK-A inhibited its tetramer formation and pyruvic acid kinase activity but promoted the nuclear accumulation of PKM2. EMT and aerobic glycolysis activated by nuclear PKM2 enhance CRC cells' migration ability and anoikis resistance during CRLM progression. TEPP-46 treatment, targeting the phosphorylation of PKM2, inhibited the pro-metastatic effect of KHK-A. Besides, c-myc activated by nuclear PKM2 promotes alternative splicing of KHK-A, forming a positive feedback loop.
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The loop B3 of glycoside hydrolase family 7 (GH7) endoglucanases is confined into long and short types. TtCel7 is a thermophilic GH7 endoglucanase from Thermothelomyces thermophilus ATCC 42464 with a long loop B3. TtCel7 was distinct for the excellent thermostability (>30 % residual activity after 1-h incubation at 90 °C). The catalytic efficiency was reduced by removing the disulfide bond in loop B3 (C220A) and truncated the loop B3 (B3cut). However, B3cut exhibited improved thermostability, the remaining enzyme activity increased by 39 %-171 % compared toTtCel7 when treated at 70-90 °C for 1-h. Based on the analysis of molecular dynamics simulation, both loops B1 and A3 of B3cut swing toward the catalytic center, which contributed to the reduced cleft-space and increased structure-rigidity. Conversely, the deletion of disulfide bond resulted in a reduction of structural rigidity in C220A. Through structure-directed enzyme modulation, this study has identified two structural elements that are related to the catalysis and thermostability of TtCel7. The loop B3 of TtCel7 possibly stretches the catalytic pocket, thereby increases the openness of the catalytic tunnel and enhancing flexibility for efficient catalysis. Additionally, the disulfide bond within loop B3 serves to enhance structural stability and maintain a heightened level of activity.
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Celulase , Glicosídeo Hidrolases , Celulase/química , Simulação de Dinâmica Molecular , Domínios Proteicos , Dissulfetos , Estabilidade EnzimáticaRESUMO
BACKGROUND: Recent research has highlighted the versatile functions of long non-coding RNAs (lncRNAs) in the onset and progression of various malignancies. Still, insufficient knowledge is available on how lnc-SOX9-4 functions in colorectal cancer (CRC) progression. METHODS: Bioinformatics analysis was used to identify a novel lncRNA (lnc-SOX9-4), and the expression pattern of the RNA in CRC was verified using qRT-PCR. Gene ontology (GO) term analysis and Gene set enrichment analysis (GSEA) were implemented for the identification of the related mechanisms and roles of lnc-SOX9-4. Immune infiltration analysis was conducted for assessment of how lnc-SOX9-4 is linked to tumor immune cell infiltration level. Both in vitro and in vivo phenotype analyses were conducted for scrutinizing how lnc-SOX9-4 impacts the proliferation and metastasis of CRC. RNA pulldown, mass spectrometry analysis, fluorescent in situ hybridization (FISH), western blotting, and RIP assay aided in verifying lnc-SOX9-4 mechanisms linked to CRC progression. RESULTS: An upregulation of lnc-SOX9-4 was observed in the sample CRC cells and tissues. Elevated lnc-SOX9-4 levels showed a positive association with poor clinical prognosis. Lnc-SOX9-4 was closely correlated to several types of immune infiltrating cells. Functionally, the knockdown of lnc-SOX9-4 significantly inhibited CRC cell proliferation, migration, and invasion abilities. Mechanistically, YBX1 was identified as lnc-SOX9-4, specifically interacting protein in the nucleus. Lnc-SOX9-4 could stabilize YBX1 protein levels by inhibiting poly-ubiquitination and degradation of YBX1. Furthermore, phenotype rescue experiments reveal that lnc-SOX9-4 enhanced the CRC cellular potential to proliferate and metastasize by regulating YBX1 levels. CONCLUSIONS: Lnc-SOX9-4 promoted CRC progression by suppressing cytoplasmic translocation and promoting protein levels of YBX1 can serve as novel treatment targets for diagnosing and treating CRC.
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Neoplasias Colorretais , RNA Longo não Codificante , Humanos , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Hibridização in Situ Fluorescente , RNA/metabolismo , Ubiquitinação , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismoRESUMO
Ubiquitin-conjugating enzyme E2 J1 (UBE2J1) has been proven to participate in the ubiquitination of multiple substrate proteins. However, the underlying mechanisms of UBE2J1 as a ubiquitin-conjugating enzyme participating in cancer development and progression remain largely unknown. Here, we identified that UBE2J1 is downregulated in colorectal cancer (CRC) tissues and cell lines which are mediated by DNA hypermethylation of its promoter, and decreased UBE2J1 is associated with poor prognosis. Functionally, UBE2J1 serving as a suppressor gene inhibits the proliferation and metastasis of CRC cells. Mechanistically, UBE2J1-TRIM25, forming an E2-E3 complex, physically interacts with and targets RPS3 for ubiquitination and degradation at the K214 residue. The downregulated RPS3 caused by UBE2J1 overexpression restrains NF-κB translocation into the nucleus and therefore inactivates the NF-κB signaling pathway. Our study revealed a novel role of UBE2J1-mediated RPS3 poly-ubiquitination and degradation in disrupting the NF-κB signaling pathway, which may serve as a novel and promising biomarker and therapeutic target for CRC.
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Neoplasias Colorretais , NF-kappa B , Humanos , NF-kappa B/metabolismo , Ubiquitinação , Enzimas de Conjugação de Ubiquitina/genética , Transdução de Sinais , Neoplasias Colorretais/patologia , Proteínas Ribossômicas/metabolismoRESUMO
OBJECTIVE: Our aim was to establish a chemiluminescence method for detecting anti-transmembrane protein (p7) antibody in the serum of patients with hepatitis C virus (HCV) infection. METHODS: The p7 gene was amplified by polymerase chain reaction using the plasmid PUC-p7 containing the p7 nucleic acid sequence of the HCV 1b genotype as the template, and recombinant plasmid pGEX-KG-p7 was constructed. After p7 fusion, the protein was induced and expressed in the prokaryote, extracted, and purified; the anti-p7 antibody detection kit was prepared, and its efficacy was evaluated. RESULTS: The plasmid pGEX-KG-p7 was constructed correctly, and p7 fusion protein was obtained. The methodological indexes of the kit, the precision test, blank limit and detection limit, etc, met the requirements. The positive rate of serum anti-p7 antibody in 45 patients with HCV infection was 20%. CONCLUSIONS: The kit can be used in screening diagnosis, condition monitoring, prognosis, and disease mechanism and epidemiological study of HCV infection. The p7 protein has immune response in HCV-infected patients.
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Hepacivirus , Hepatite C , Humanos , Hepacivirus/genética , Luminescência , Hepatite C/diagnóstico , Reação em Cadeia da Polimerase , Proteínas Recombinantes/genéticaRESUMO
Phages are prevalent in diverse environments and play major ecological roles attributed to their tremendous diversity and abundance. Among these viruses, transposable phages (TBPs) are exceptional in terms of their unique lifestyle, especially their replicative transposition. Although several TBPs have been isolated and the life cycle of the representative phage Mu has been extensively studied, the diversity distribution and ecological functions of TBPs on the global scale remain unknown. Here, by mining TBPs from enormous microbial genomes and viromes, we established a TBP genome dataset (TBPGD), that expands the number of accessible TBP genomes 384-fold. TBPs are prevalent in diverse biomes and show great genetic diversity. Based on taxonomic evaluations, we propose the categorization of TBPs into four viral groups, including 11 candidate subfamilies. TBPs infect multiple bacterial phyla, and seem to infect a wider range of hosts than non-TBPs. Diverse auxiliary metabolic genes (AMGs) are identified in the TBP genomes, and genes related to glycoside hydrolases and pyrimidine deoxyribonucleotide biosynthesis are highly enriched. Finally, the influences of TBPs on their hosts are experimentally examined by using the marine bacterium Shewanella psychrophila WP2 and its infecting transposable phage SP2. Collectively, our findings greatly expand the genetic diversity of TBPs, and comprehensively reveal their potential influences in various ecosystems.
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Bacteriófagos , Vírus , Bacteriófagos/genética , Ecossistema , Genoma Viral , Vírus/genética , Bactérias/genéticaRESUMO
Currently, definitive treatment for neurodegenerative diseases without side effects has not been developed, therefore, exploring natural polysaccharides with neuroprotection to prevent the occurrences and progressions of cognitive dysfunctions has important significance. The purpose of this study was to investigate the effects of sea buckthorn polysaccharide (SBP) on high-fat diet (HFD) induced mice cognitive dysfunctions and attempted to explore its biological mechanisms. Behavior tests (Y-maze and Barnes maze) suggested that SBP effectively alleviated the HFD induced behavioral disorders, which was in accordance with the inhibition of neuroinflammation via suppressing the NF-κB pathway and amelioration of synaptic dysfunction via upregulating CREB/BDNF/TrkB pathway in mice brain. Furthermore, SBP alleviated the gut barrier impairment, inflammatory responses, and lipopolysaccharide invasion into blood circulation via regulating the gut microbiome structure, especially correcting the reduction of Ileibacterium and increase of Lactobacillus, Dubosiella, Olsenella, Helicobacter, and Ruminiclostridium_9 in HFD mice. Therefore, the reversal effects of SBP on gut dysbiosis might be the important reason for its positive effects on cognitive dysfunction induced by HFD in mice.
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Hippophae , Obesidade , Camundongos , Animais , Obesidade/metabolismo , Doenças Neuroinflamatórias , Dieta Hiperlipídica/efeitos adversos , Disbiose/microbiologia , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Camundongos Endogâmicos C57BLRESUMO
Viruses are ubiquitous in the oceans, exhibiting high abundance and diversity. Here, we systematically analyze existing genomic sequences of marine prokaryotes to compile a Marine Prokaryotic Genome Dataset (MPGD, consisting of over 12,000 bacterial and archaeal genomes) and a Marine Temperate Viral Genome Dataset (MTVGD). At least 40% of the MPGD genomes contain one or more proviral sequences, indicating that they are lysogens. The MTVGD includes over 12,900 viral contigs or putative proviruses, clustered into 10,897 viral genera. We show that lysogens and proviruses are abundant in marine ecosystems, particularly in the deep sea, and marine lysogens differ from non-lysogens in multiple genomic features and growth properties. We reveal several virus-host interaction networks of potential ecological relevance, and identify proviruses that appear to be able to infect (or to be transferred between) different bacterial classes and phyla. Auxiliary metabolic genes in the MTVGD are enriched in functions related to carbohydrate metabolism. Finally, we experimentally demonstrate the impact of a prophage on the transcriptome of a representative marine Shewanella bacterium. Our work contributes to a better understanding of the ecology of marine prokaryotes and their viruses.
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Provírus , Vírus , Provírus/genética , Ecossistema , Oceanos e Mares , Genoma Viral , Bactérias/genética , Vírus/genética , FilogeniaRESUMO
CP fandom behaviors or shipping, a growing popular phenomenon among Chinese young adults, refers to the activities of fans who take great satisfaction from the romantic relationships and interactions of their preferred pairings of idols or virtual characters. CP fans are regarded as a special group of fans with unique identities and interaction styles. This grounded theory study was conducted to explore the mechanism of CP fandom behaviors. Semi-structured in-depth interviews were conducted with thirty-one Chinese CP fans (twenty-eight females and three males). The antecedents, development, behavioral patterns, and consequences of shipping were identified in a comprehensive model. The reasons for CP fandom behaviors include individual factors (e.g., psychological projection, compensation, and social needs) and external factors (e.g., pop culture and internet environment). The consequences include positive emotional experiences, changed love values, and improved social interaction. CP fandom behaviors can be different in terms of the fans' degrees of engagement, and the development of shipping can be divided into three stages: exploratory stage, formation and stability stage, and rupture stage. This study contributes to the literature of CP fandom behaviors among young adults in China and proposes the directions of future studies on such topics.
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Objective: We detected the serum HBsAg immune complex (HBsAg-CIC) and sequenced the HBV S gene in these patients to reveal the association between sustained low-level expression of HBsAg and mutated S gene sequence characteristics, protein function changes, and HBsAg immune complex formation. Methods: A total of 204 samples were collected and divided into high-level (n = 60, HBsAg level >10 IU/ml) and low-level (n = 144, HBsAg level ≤ 10 IU/ml) HBsAg groups. The clinical and epidemiological data of the two groups were statistically compared. According to different serological patterns and genotypes, the HBsAg-CIC results of the high-level and low-level HBsAg groups were divided into different subgroups, and then the HBsAg-CIC positive rates among different subgroups were compared. We sequenced the S gene of HBV from the two groups and identified the relevant mutations in the MHR of the S gene. In addition, we compared the changes in HBsAg protein properties and functions after hot spot mutation in the MHR of the S gene. Results: Comparing the positive rates of HBsAg-CIC under different serological patterns and genotypes in the two groups, the HBsAg-CIC positive rate was higher in the low-level HBsAg group. Moreover, there was weak correlation between HBsAg-CIC and HBsAg or HBV DNA in both groups (r = 0.32, 0.27, 0.41, 0.48; P < 0.05). Sequencing of S gene in the two groups, showed that the hot-spot mutations were T126A, M133L/T/S, and F134L/T/I in MHR of S gene of genotype B, and hot-spot mutations were Q101R and I126S/T in MHR of S gene of genotype C. Additionally, the positive rate of MHR mutation in the S gene from HBsAg-CIC positive patients was higher in the low-level HBsAg group. Conclusion: The host immune process of clearing HBV seems to have multiple site mutations in MHR, which changes the physicochemical properties and functions of HBsAg and intensifies the formation of HBsAg-CIC, thus avoiding the effective recognition of HBsAg by the host and resulting in immune tolerance between the host and HBV, which may be one of the formation mechanisms of sustained low-level expression of HBsAg in the serum of HBV-infected persons.
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N7-Methylguanosine (m7G) modifications are a common type of posttranscriptional RNA modifications. Its function in the tumor microenvironment (TME) has garnered widespread focus in the past few years. Long non-coding RNAs (lncRNAs) played an essential part in tumor development and are closely associated with the tumor immune microenvironment. In this study, we employed a comprehensive bioinformatics approach to develop an m7G-associated lncRNA prognostic model based on the colon adenocarcinoma (COAD) database from The Cancer Genome Atlas (TCGA) database. Pearson's correlation analysis was performed to identify m7G-related lncRNAs. Differential gene expression analysis was used to screen lncRNAs. Then, we gained 88 differentially expressed m7G-related lncRNAs. Univariate Cox analysis and Lasso regression analysis were performed to build an eight-m7G-related-lncRNA (ELFN1-AS1, GABPB1-AS1, SNHG7, GS1-124K5.4, ZEB1-AS1, PCAT6, C1RL-AS1, MCM3AP-AS1) risk model. Consensus clustering analysis was applied to identify the m7G-related lncRNA subtypes. We also verified the risk prediction effect of a gene signature in the GSE17536 test set (177 patients). A nomogram was constructed to predict overall survival rates. Furthermore, we analyzed differentially expressed genes (DEGs) between high-risk and low-risk groups. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted with the analyzed DEGs. At last, single-sample gene set enrichment analysis (ssGSEA), CIBERSORT, MCP-COUNTER, and Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) algorithms were utilized to discover the relationship between the risk model and the TME. Consequently, the m7G-related lncRNA risk model for COAD patients could be a viable prognostic tool and treatment target.
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OBJECTIVES: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is increasingly reported worldwide and has posed a serious challenge for public health. Here we report the complete genome sequence of a multidrug-resistant (MDR) K. pneumoniae carrying one blaNDM-1 and two copies of blaKPC-2 genes isolated from a cerebrospinal fluid specimen in China. METHODS: The minimal inhibitory concentrations (MICs) of 26 antimicrobial agents against K. pneumoniae strain KP46 were measured. The complete genome sequence of KP46 was determined using Illumina and Nanopore platforms. The derived short and long reads were assembled using Unicycler. Multilocus sequence typing (MLST), antimicrobial resistance genes, virulence genes, and plasmid replicons were predicted in silico using the BacWGSTdb server. The phylogenetic relationship between KP46 and 454 ST15 K. pneumoniae strains obtained from NCBI GenBank database was analysed based on a core genome MLST (cgMLST) strategy. RESULTS: K. pneumoniae strain KP46 was resistant to all antimicrobial agents tested, except for tigecycline, colistin, cefiderocol, and fosfomycin. The genome sequence of KP46 belonged to sequence type 15 (ST15), which contained seven circularized contigs comprising 5 674 521 bp, including one chromosome and six plasmids. Serval antimicrobial resistance genes were identified, including a blaNDM-1 gene located in a 53 096 bp IncX3 plasmid, and two copies of blaKPC-2 gene located both in a 103 807 bp IncX6 and an 88 164 bp IncFII plasmid, respectively. The most closely related strain was another ST15 strain also isolated from China with five cgMLST loci differences. CONCLUSION: We reported the first complete genome sequence of a K. pneumoniae ST15 clinical isolate coharbouring blaNDM-1 and two copies of blaKPC-2 in China. This study will provide insight into the antimicrobial resistance mechanisms and phylogeny of carbapenem-resistant ST15 K. pneumoniae.
Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla , Humanos , Infecções por Klebsiella/líquido cefalorraquidiano , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , Filogenia , beta-LactamasesRESUMO
This study investigated the fermentation performances and aroma compositions of synthetic grape juice that was fermented by four indigenous non-Saccharomyces yeast isolates that were obtained from the Shangri-La wine region (China): Meyerozyma guilliermondii (AD-58), Saccharomycopsis vini (BZL-28), Saturnispora diversa (BZL-11), and Wickerhamomyces anomalus (DR-110), in comparison to those of Saccharomyces cerevisiae (EC1118). The four indigenous non-Saccharomyces yeasts showed a lower fermentative capacity and a lower conversion rate of sugar to alcohol, but a higher yield of volatile acidity. W. anomalus (DR-110) had a greater ability to produce numerous esters and short-chain fatty acids and the representative flavors of its fermented medium were fruity and fatty. Sac.vini (BZL-28), interestingly, exhibited great capacity in the formation of many monoterpenes, particularly (Z)-ß-ocimene, E-ß-ocimene, linalool, citral, and geraniol and its fermented medium was characterized by a strong fruity (citrus-like) and floral flavor. M. guilliermondii (AD-58) and Sat. diversa (BZL-11) only mildly affected the aroma profiles of their resultant fermented media, since the concentrations of most of the volatiles that were produced by these two isolates were much lower than their sensory thresholds. The four indigenous non-Saccharomyces yeasts exhibited distinctive fermentation performances and aroma production behaviors. In particularly, W. anomalus (DR-110) and Sac. vini (BZL-28) have shown good potential in enhancing the aromas and complexity of wine.