Genome-Wide Analysis of the Response of Brucella melitensis NI to Polymyxin B

2020 ◽  
Vol 21 ◽  
Author(s):  
Zhen Wang ◽  
Jiawei Wang ◽  
Jie Cheng ◽  
Xiaowen Yang ◽  
Hai Jiang ◽  
...  
Keyword(s):  
Differentially Expressed Genes ◽  
Virulence Factors ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Target Genes ◽  
Brucella Melitensis ◽  
Polymyxin B ◽  
Differentially Expressed ◽  
Cold Shock Protein ◽  
Genes Encoding

Background: The ability of pathogenic bacteria to survive antimicrobial peptides (AMPs) in various host niches may contribute to their virulence. Polymyxin B is a cationic AMP, and polymyxin drugs are considered to be the "last line of defense" in the clinical treatment of bacterial infections. Objective: The objectives of this study were to comprehensively study the response of Brucella melitensis strain NI to polymyxin B treatment and to identify the target genes in Brucella induced by polymyxin B stimulation. Methods: Following treatment with polymyxin B, differentially expressed genes in Brucella were detected using RNA-seq and validated using qRT-PCR. Results: In total, 874 differentially expressed genes were identified, including 560 up-regulated and 314 down-regulated genes. Functional annotation and KEGG pathway analysis revealed that many of these genes are involved in metabolism, two-component systems, transcriptional regulation, transport/membrane proteins, and virulence factors. Expression of genes involved in T4SS and flagellar biosynthesis and assembly, which are important virulence factors in Brucella, were upregulated by polymyxin B treatment. Discussion: Additionally, genes encoding the ABC transporters YejABEF and the cold-shock protein CspA were also upregulated. These genes confer resistance to AMPs and contribute to the virulence of Brucella. The NI∆sufC, NI∆sufD, NI∆ompW, NI∆exbB, NI∆tetR, and NI∆cspA mutants were also more sensitive than B. melitensis NI to polymyxin B. Conclusion: The results of this study provide important insights into the comprehensive response of Brucella in response to polymyxin B stimulation.

scholarly journals Uterine infection alters the transcriptome of the bovine reproductive tract three months later

Reproduction ◽  
2020 ◽  
Vol 160 (1) ◽  
pp. 93-107 ◽  
Author(s):  
Anthony D Horlock ◽  
Rachel L Piersanti ◽  
Rosabel Ramirez-Hernandez ◽  
Fahong Yu ◽  
Zhengxin Ma ◽  
...  
Keyword(s):  
Differentially Expressed Genes ◽  
Granulosa Cells ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Reproductive Tract ◽  
Negative Energy ◽  
Differentially Expressed ◽  
Long Term Changes ◽  
Bacterial Infusion

Infection of the postpartum uterus with pathogenic bacteria is associated with infertility months later in dairy cattle. However, it is unclear whether these bacterial infections lead to long-term changes in the reproductive tract that might help explain this infertility. Here we tested the hypothesis that infusion of pathogenic bacteria into the uterus leads to changes in the transcriptome of the reproductive tract 3 months later. We used virgin Holstein heifers to avoid potential confounding effects of periparturient problems, lactation, and negative energy balance. Animals were infused intrauterine with endometrial pathogenic bacteria Escherichia coli and Trueperella pyogenes (n = 4) and compared with control animals (n = 6). Three months after infusion, caruncular and intercaruncular endometrium, isthmus and ampulla of the oviduct, and granulosa cells from ovarian follicles >8 mm diameter were profiled by RNA sequencing. Bacterial infusion altered the transcriptome of all the tissues when compared with control. Most differentially expressed genes were tissue specific, with 109 differentially expressed genes unique to caruncular endometrium, 57 in intercaruncular endometrium, 65 in isthmus, 298 in ampulla, and 83 in granulosa cells. Surprisingly, despite infusing bacteria into the uterus, granulosa cells had more predicted upstream regulators of differentially expressed genes than all the other tissues combined. In conclusion, there were changes in the transcriptome of the endometrium, oviduct and even granulosa cells, 3 months after intrauterine infusion of pathogenic bacteria. These findings imply that long-term changes throughout the reproductive tract could contribute to infertility after bacterial infections of the uterus.

Long-Living Budding Yeast Cell Subpopulation Induced by Ethanol/Acetate and Respiration

2019 ◽  
Vol 75 (8) ◽  
pp. 1448-1456 ◽  
Author(s):  
Young-Yon Kwon ◽  
Seung-Soo Kim ◽  
Han-Jun Lee ◽  
Seo-Hyeong Sheen ◽  
Kyoung Heon Kim ◽  
...  
Keyword(s):  
Differentially Expressed Genes ◽  
Budding Yeast ◽  
Gradient Centrifugation ◽  
Carbon Sources ◽  
Cell Types ◽  
Glucose Sensing ◽  
Differentially Expressed ◽  
Cell Subpopulation ◽  
Genes Encoding ◽  
Cell Transcriptome

Abstract Budding yeast generate heterogeneous cells that can be separated into two distinctive cell types: short-living low-density and long-living high-density (HD) cells by density gradient centrifugation. We found that ethanol and acetate induce formation of HD cells, and mitochondrial respiration is required. From their transcriptomes and metabolomes, we found upregulated differentially expressed genes in HD cells involved in the RGT2/RGT1 glucose sensing pathway and its downstream genes encoding hexose transporters. For HD cells, we determined an abundance of various carbon sources including glucose, lactate, pyruvate, trehalose, mannitol, mannose, and galactose. Other upregulated differentially expressed genes in HD cells were involved in the TORC1–SCH9 signaling pathway and its downstream genes involved in cytoplasmic translation. We also measured an abundance of free amino acids in HD cells including valine, proline, isoleucine, and glutamine. These characteristics of the HD cell transcriptome and metabolome may be important conditions for maintaining a long-living phenotype.

The RNA-seq approach to discriminate gene expression profiles in response to Beauveria bassiana and Micrococcus luteus microbial pathogens on Actias selene (Lepidoptera: Saturniidae)

Zootaxa ◽  
2019 ◽  
Vol 4591 (1) ◽  
pp. 1
Author(s):  
DAN LIANG ◽  
PEI WANG ◽  
LINGLING WU ◽  
XIAOLI JIANG ◽  
GUOQING WEI ◽  
...  
Keyword(s):  
Differentially Expressed Genes ◽  
Beauveria Bassiana ◽  
Bacterial Infections ◽  
Micrococcus Luteus ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Differentially Expressed ◽  
Microbial Pathogens ◽  
Pcr Analysis ◽  
Immune Mechanism

Actias selene (Hübner) is an important silk-spinning moth. Like other moths, it has innate immunity but no acquired immunity. However, there are few studies on immune-related genes of A. selene. Here, differential expression RNAseq experiment was employed to examine the genes related to different metabolic pathways and to explore the immune mechanism of the A. selene post Beauveria bassiana (Bb) and Micrococcus luteus (ML) stimuli. A total of 64,372,921 clean reads were obtained and 39,057 differentially expressed genes (DEGs) were identified. In the Bb vs. PBS group (PBS as the control), 9,092 genes were up-regulated and 4,438 genes were down-regulated; in the ML vs. PBS group, 5,903 genes were up-regulated and 5,175 genes were down-regulated. The KEGG (Kyoto Encyclopedia of Genes and Genomes) and GO (Gene Ontology) analyses of DEGs confirmed that many DEGs were associated with "Metabolism pathway", "cellular process", "cell" and "catalytic activity". Among them, 194 and 149 differentially expressed genes were related to immunity in the Bb vs. PBS group and ML vs. PBS group, respectively. We verified the reliability of the data with reverse transcription quantitative real-time PCR analysis of randomly selected genes. Furthermore, the phylogenetic tree results showed that HSP90, PGRP and MyD88 genes of A. selene were most closely related to Antheraea pernyi (Guérin-Méneville). These results will provide an overview of the molecular mechanism of A. selene resistance to fungal and bacterial infections as well as an evolutionary aspect of these genes. Moreover, the interrelated trophic mechanisms among different groups of organisms are vital to explore, thus this study will lay a foundation for further studies on the innate immune mechanism of saturniid moths, and provide important theoretical basis for studying the relationship between A. selene and other species.

scholarly journals Microarray-Based Characterization of the Listeria monocytogenes Cold Regulon in Log- and Stationary-Phase Cells

2007 ◽  
Vol 73 (20) ◽  
pp. 6484-6498 ◽  
Author(s):  
Yvonne C. Chan ◽  
Sarita Raengpradub ◽  
Kathryn J. Boor ◽  
Martin Wiedmann
Keyword(s):  
Listeria Monocytogenes ◽  
Heat Shock ◽  
Stationary Phase ◽  
Response Regulator ◽  
Differentially Expressed ◽  
Cold Shock Protein ◽  
Rna Helicases ◽  
Transcript Levels ◽  
Number Of Genes ◽  
Genes Encoding

ABSTRACT Whole-genome microarray experiments were performed to define the Listeria monocytogenes cold growth regulon and to identify genes differentially expressed during growth at 4 and 37°C. Microarray analysis using a stringent cutoff (adjusted P < 0.001; ≥2.0-fold change) revealed 105 and 170 genes that showed higher transcript levels in logarithmic- and stationary-phase cells, respectively, at 4°C than in cells grown at 37°C. A total of 74 and 102 genes showed lower transcript levels in logarithmic- and stationary-phase cells, respectively, grown at 4°C. Genes with higher transcript levels at 4°C in both stationary- and log-phase cells included genes encoding a two-component response regulator (lmo0287), a cold shock protein (cspL), and two RNA helicases (lmo0866 and lmo1722), whereas a number of genes encoding virulence factors and heat shock proteins showed lower transcript levels at 4°C. Selected genes that showed higher transcript levels at 4°C during both stationary and log phases were confirmed by quantitative reverse transcriptase PCR. Our data show that (i) a large number of L. monocytogenes genes are differentially expressed at 4 and 37°C, with more genes showing higher transcript levels than lower transcript levels at 4°C, (ii) L. monocytogenes genes with higher transcript levels at 4°C include a number of genes and operons with previously reported or plausible roles in cold adaptation, and (iii) L. monocytogenes genes with lower transcript levels at 4°C include a number of virulence and virulence-associated genes as well as some heat shock genes.

scholarly journals Transcriptional modulator ZBED6 affects cell cycle and growth of human colorectal cancer cells

2015 ◽  
Vol 112 (25) ◽  
pp. 7743-7748 ◽  
Author(s):  
Muhammad Akhtar Ali ◽  
Shady Younis ◽  
Ola Wallerman ◽  
Rajesh Gupta ◽  
Leif Andersson ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Cycle ◽  
Cell Lines ◽  
Differentially Expressed Genes ◽  
Target Genes ◽  
Egf Receptor ◽  
Differentially Expressed ◽  
Striking Difference ◽  
Human Colorectal Cancer ◽  
Chip Sequencing

The transcription factor ZBED6 (zinc finger, BED-type containing 6) is a repressor of IGF2 whose action impacts development, cell proliferation, and growth in placental mammals. In human colorectal cancers, IGF2 overexpression is mutually exclusive with somatic mutations in PI3K signaling components, providing genetic evidence for a role in the PI3K pathway. To understand the role of ZBED6 in tumorigenesis, we engineered and validated somatic cell ZBED6 knock-outs in the human colorectal cancer cell lines RKO and HCT116. Ablation of ZBED6 affected the cell cycle and led to increased growth rate in RKO cells but reduced growth in HCT116 cells. This striking difference was reflected in the transcriptome analyses, which revealed enrichment of cell-cycle–related processes among differentially expressed genes in both cell lines, but the direction of change often differed between the cell lines. ChIP sequencing analyses displayed enrichment of ZBED6 binding at genes up-regulated in ZBED6-knockout clones, consistent with the view that ZBED6 modulates gene expression primarily by repressing transcription. Ten differentially expressed genes were identified as putative direct gene targets, and their down-regulation by ZBED6 was validated experimentally. Eight of these genes were linked to the Wnt, Hippo, TGF-β, EGF receptor, or PI3K pathways, all involved in colorectal cancer development. The results of this study show that the effect of ZBED6 on tumor development depends on the genetic background and the transcriptional state of its target genes.

scholarly journals Inferring the genetic responses to acute drought stress across an ecological gradient

BMC Genomics ◽  
2022 ◽  
Vol 23 (1) ◽  
Author(s):  
Jessica K. Devitt ◽  
Albert Chung ◽  
John J. Schenk
Keyword(s):  
Drought Stress ◽  
Differentially Expressed Genes ◽  
Target Genes ◽  
De Novo ◽  
Water Movement ◽  
Model Systems ◽  
Differentially Expressed ◽  
Model Organisms ◽  
Ecological Gradient ◽  
Genetic Responses

Abstract Background How do xerophytic species thrive in environments that experience extreme annual drought? Although critical to the survival of many species, the genetic responses to drought stress in many non-model organisms has yet to be explored. We investigated this question in Mentzelia section Bartonia (Loasaceae), which occurs throughout western North America, including arid lands. To better understand the genetic responses to drought stress among species that occur in different habitats, the gene expression levels of three species from Mentzelia were compared across a precipitation gradient. Two de novo reference transcriptomes were generated and annotated. Leaf and root tissues were collected from control and drought shocked plants and compared to one another for differential expression. A target-gene approach was also implemented to better understand how drought-related genes from model and crop species function in non-model systems. Results When comparing the drought-shock treatment plants to their respective control plants, we identified 165 differentially expressed clusters across all three species. Differentially expressed genes including those associated with water movement, photosynthesis, and delayed senescence. The transcriptome profiling approach was coupled with a target genes approach that measured expression of 90 genes associated with drought tolerance in model organisms. Comparing differentially expressed genes with a ≥ 2 log-fold value between species and tissue types showed significant differences in drought response. In pairwise comparisons, species that occurred in drier environments differentially expressed greater genes in leaves when drought shocked than those from wetter environments, but expression in the roots mostly produced opposite results. Conclusions Arid-adapted species mount greater genetic responses compared to the mesophytic species, which has likely evolved in response to consistent annual drought exposure across generations. Drought responses also depended on organ type. Xerophytes, for example, mounted a larger response in leaves to downregulate photosynthesis and senescence, while mobilizing carbon and regulating water in the roots. The complexity of drought responses in Mentzelia suggest that whole organism responses need to be considered when studying drought and, in particular, the physiological mechanisms in which plants regulate water, carbon, cell death, metabolism, and secondary metabolites.

scholarly journals Whole Genome Sequence Analysis of Brucella melitensis Phylogeny and Virulence Factors

2021 ◽  
Vol 12 (3) ◽  
pp. 698-710
Author(s):  
Peter Rabinowitz ◽  
Bar Zilberman ◽  
Yair Motro ◽  
Marilyn C. Roberts ◽  
Alex Greninger ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Pathogenic Bacteria ◽  
Virulence Genes ◽  
Brucella Melitensis ◽  
Geographic Region ◽  
Clinical Severity ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
Pan Genome ◽  
Wide Range

Brucellosis has a wide range of clinical severity in humans that remains poorly understood. Whole genome sequencing (WGS) analysis may be able to detect variation in virulence genes. We used Brucella melitensis sequences in the NCBI Sequence Read Archive (SRA) database to assemble 248 whole genomes, and additionally, assembled 27 B. melitensis genomes from samples of human patients in Southern Israel. We searched the 275 assembled genomes for the 43 B. melitensis virulence genes in the Virulence Factors of Pathogenic Bacteria Database (VFDB) and 10 other published putative virulence genes. We explored pan-genome variation across the genomes and in a pilot analysis, explored single nucleotide polymorphism (SNP) variation among the ten putative virulence genes. More than 99% of the genomes had sequences for all Brucella melitensis virulence genes included in the VFDB. The 10 other virulence genes of interest were present across all the genomes, but three of these genes had SNP variation associated with particular Brucella melitensis genotypes. SNP variation was also seen within the Israeli genomes obtained from a small geographic region. While the Brucella genome is highly conserved, this novel and large whole genome study of Brucella demonstrates the ability of whole genome and pan-genome analysis to screen multiple genomes and identify SNP variation in both known and novel virulence genes that could be associated with differential disease virulence. Further development of whole genome techniques and linkage with clinical metadata on disease outcomes could shed light on whether such variation in the Brucella genome plays a role in pathogenesis.

scholarly journals Transcriptomic Analysis of Viable but Non-Culturable Escherichia coli O157:H7 Formation Induced by Low Temperature

2019 ◽  
Vol 7 (12) ◽  
pp. 634 ◽  
Author(s):  
Junliang Zhong ◽  
Xihong Zhao
Keyword(s):  
Escherichia Coli ◽  
Low Temperature ◽  
Differentially Expressed Genes ◽  
Pathogenic Bacteria ◽  
Differentially Expressed ◽  
Transmembrane Transport ◽  
Pathway Enrichment Analysis ◽  
Escherichia Coli O157 ◽  
Vbnc State ◽  
E Coli

Escherichia coli O157:H7 is one of the most common pathogenic bacteria that pose a threat to food safety. The aim of this study was to investigate the mechanisms of the formation of viable but non-culturable (VBNC) E. coli O157:H7 induced by low temperature (−20 °C) using RNA sequencing (RNA-Seq) transcriptomics analysis. The results of the present investigation revealed the presence of 2298 differentially expressed genes in VBNC cells, accounting for 46.03% of the total number of genes. Additionally, GO function and KEGG pathway enrichment analysis were performed to investigate the functional and related metabolic pathways of the differentially expressed genes. We found that the ion transport, protein synthesis, and protein transmembrane transport activities were significantly improved in the VBNC cells, indicating that E. coli O157:H7 cells synthesized a considerable amount of protein to maintain the levels of their functional metabolic processes and life activities in the VBNC state. In conclusion, we suggest that the increased synthesis of proteins such as SecY, FtsY, and Ffh might indicate that they are the key proteins involved in the improvement of the transmembrane transport activities in VBNC E. coli O157:H7 cells, maintaining their functional metabolism in the VBNC state and enhancing their survival ability under low temperatures.

scholarly journals Relation between Biofilm and Virulence in Vibrio tapetis: A Transcriptomic Study

Pathogens ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 92 ◽  
Author(s):  
Sophie Rodrigues ◽  
Christine Paillard ◽  
Sabine Van Dillen ◽  
Ali Tahrioui ◽  
Jean-Marc Berjeaud ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Cell System ◽  
Ruditapes Philippinarum ◽  
Differentially Expressed ◽  
Type Vi Secretion System ◽  
Altered Expression ◽  
Expression Of Genes ◽  
Polysaccharide Synthesis ◽  
Genes Encoding ◽  
Genetic Level

Marine pathogenic bacteria are able to form biofilms on many surfaces, such as mollusc shells, and they can wait for the appropriate opportunity to induce their virulence. Vibrio tapetis can develop such biofilms on the inner surface of shells of the Ruditapes philippinarum clam, leading to the formation of a brown conchiolin deposit in the form of a ring, hence the name of the disease: Brown Ring Disease. The virulence of V. tapetis is presumed to be related to its capacity to form biofilms, but the link has never been clearly established at the physiological or genetic level. In the present study, we used RNA-seq analysis to identify biofilm- and virulence-related genes displaying altered expression in biofilms compared to the planktonic condition. A flow cell system was employed to grow biofilms to obtain both structural and transcriptomic views of the biofilms. We found that 3615 genes were differentially expressed, confirming that biofilm and planktonic lifestyles are very different. As expected, the differentially expressed genes included those involved in biofilm formation, such as motility- and polysaccharide synthesis-related genes. The data show that quorum sensing is probably mediated by the AI-2/LuxO system in V. tapetis biofilms. The expression of genes encoding the Type VI Secretion System and associated exported proteins are strongly induced, suggesting that V. tapetis activates this virulence factor when living in biofilm.

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