Whole genome sequencing of S. aureus strains Xen31 and Xen36
Ontology highlight
ABSTRACT: Here, we report genome sequences of the two bioluminescent S. aureus strains Xen31 and Xen36, obtained from PerkinElmer (#119242 and #119243, respectively). Xen31 was derived from the parental MRSA strain ATCC33591, a clinical strain isolated at Elmhurst Hospital in New York City. Xen36 was derived from parental strain ATCC 49525, a clinical isolate from a bacteremic patient. A copy of the modified luxABCDE operon from Photorhadbus luminescenst is integrated in the chromosome of Xen31 and in a native plasmid of Xen36.
Project description:JC polyomavirus (circular genome) contains two opposite coding regions separated by the regulator non-coding control region (NCCR). NCCR rearrangements and missense mutations in the viral capsid protein VP1 gene differentiate JCV prototype genomes recovered from PML lesions from archetype urine strains. To further investigate the emerging variability of JCV populations in PML, we deep sequenced JCV whole genome recovered from CNS and/or urine samples from HIV- and non HIV-infected PML patients, using single-molecule real-time sequencing (PacBio, Pacific Biosciences). Phylogenetic analysis showed that PML strains distributed among 6 of 7 known genotypes. Whole genome single molecule sequencing provides insight in the genesis of JCV neurotropic populations.
Project description:Aggregatibacter actinomycetemcomitans (Aa) is a Gram-negative bacterial pathogen associated with severe periodontitis and non-oral diseases. Clinical isolates of Aa display a rough (R) colony phenotype with strong adherent properties. Upon prolonged culturing, non-adherent strains with a smooth (S) colony phenotype emerge. To date, most virulence studies on Aa have been performed with S strains of Aa, whereas the virulence of clinical R isolates received relatively little attention. Since the extracellular proteome is the main bacterial reservoir of virulence factors, the present study was aimed at a comparative analysis of this sub-proteome fraction for a collection of R isolates and derivative S strains, in order to link particular proteins to the virulence of Aa with serotype b. To assess the bacterial virulence, we applied different infection models based on larvae of the greater wax moth Galleria mellonella, a human salivary gland-derived epithelial cell line, and freshly isolated neutrophils from healthy human volunteers. A total number of 351 extracellular Aa proteins was identified by mass spectrometry, with the S strains consistently showing more extracellular proteins than their parental R isolates. A total of 50 known extracellular virulence factors was identified, of which 15 were expressed by all investigated bacteria. Importantly, the comparison of differences in exoproteome composition and virulence highlights critical roles of 10 extracellular proteins in the different infection models. Altogether, our present study provides novel cues for understanding the virulence of Aa, and for development of potential preventive or therapeutic avenues to neutralize this important oral pathogen.
Project description:ost-pathogen interactions are often studied in vitro using primary or immortal cell lines. This set-up avoids ethical problems of animal testing and has the additional advantage of lower costs. However, the influence of cell culture media on bacterial growth and metabolism is not considered or investigated in most cases. To address this question growth and proteome adaptation of Corynebacterium diphtheriae strain ISS3319 were investigated in this study. Bacteria were cultured in standard growth medium, cell culture medium and fetal calf serum. Mass spectrometric analyses and label-free protein quantification hint to an increased bacterial pathogenicity when grown in cell culture medium as well as an influence of the growth medium on the cell envelope.
Project description:In this study, RNA-seq was used to compare the transcriptomes of Listeria monocytogenes 10403S::ÎBCHL Prha-sigH and ÎBCHL Prha. RNA-seq was performed on ÎBCHL Prha-sigH and ÎBCHL Prha RNA samples representing three independent biological replicates at log phase in Brain Heart Infusion (BHI) broth under rhamnose induction. Indexed and purified cDNA libraries (6 libraries including 3 replicates for 2 strains) were loaded together onto an independent flow cell without any other samples; sequencing was carried out by running Hiseq 2500 (single-end, 150-bp per read). Reads alignment was carried out using the Burrows-Wheeler Aligner (BWA). Differential expression of genes in different strains was statistically assessed using the BaySeq method. To identify sigH-dependent promoters, a new method of moving sliding windows of 50 nt along the whole genome was used to compare the normalized RNA-seq coverage (NRC) between the two strains. Using the standard whole gene differential expression analysis, significant upregulation of 5 genes in 4 operons was found in the sigH overexpressing strain. While with the sliding windiow analysis, 2 additional ÏH-dependent promoters were identified. Our results show that three ÏH-dependent transcritption units that encode competence proteins, including the comEABC , comGABCDEFG and coiA. Transcriptome profiles of L. monocytogenes 10403S::ÎBCHL Prha-sigH and ÎBCHL Prha were generated by deep sequencing, in triplicate, using Illumina Hiseq 2500.
Project description:The extensively studied intracellular pathogen, L. monocytogenes, is an ideal model for identifying small-molecule agents for treating bacterial infections. By selecting specific biological targets in L. monocytogenes, which are common to Gram-positive pathogens, we could extrapolate drug discovery information derived from this well-studied bacterium. Attenuating the pathogenM-bM-^@M-^Ys virulence and stress response attributes without killing it, eliminates selective pressure caused by disruption of essential gene functions (as done by current antibiotics) and reduces the likelihood of developing microbes that are impervious to the effects of antibiotics. To this end, we have assessed multiple libraries of small organic compounds to identify inhibitors of L. monocytogenes M-OM-^CB, the alternative sigma factor common to several clinically relevant Gram-positive pathogens, such as Staphylococcus aureus, Bacillus cereus, and Bacillus anthracis. The role of M-OM-^CB as a transcriptional regulator of stress response and virulence makes it an ideal, well conserved target for chemotherapeutic development. Independent RNA isolations were performed for each growth experiment (log phase cells exposed to BHI+0.3M NaCl and BHI+0.3M NaCl + CMPD). Four biological replicates were used in competitive whole-genome microarray experiments. For the hybridizations, RNA from the wildtype parent strain L. monocytogenes 10403S were hybridized to RNA from the wildtype parent strain 10403S treated with CMPD.
Project description:2 samples have been prepared for ISO-seq sequencing. CD34+ blast cells from 5 MDS patients before 5-AZA treatment (GEO531A16, GEO531A13, GEO531A5, GEO531A11, GEO531A3) were pooled to generate one sample and 2 AML non-treated and 2 CMML non-treated cells (GEO531A2, GEO531A9, GEO531A6, GEO531A7) were pooled for second sample.
Project description:RNA-seq analysis of the transcriptome of wild type C.jejuni NCTC11168, and of an rpoN mutant of the same strain, both grown in vitro.
Project description:Large-scale sequencing of RNAs from individual cells can reveal patterns of gene, isoform and allelic expression across cell types and states. However, current single-cell RNA-sequencing (scRNA-seq) methods have limited ability to count RNAs at allele- and isoform resolution, and long-read sequencing techniques lack the depth required for large-scale applications across cells. Here, we introduce Smart-seq3 that combines full-length transcriptome coverage with a 5’ unique molecular identifier (UMI) RNA counting strategy that enabled in silico reconstruction of thousands of RNA molecules per cell. Importantly, a large portion of counted and reconstructed RNA molecules could be directly assigned to specific isoforms and allelic origin, and we identified significant transcript isoform regulation in mouse strains and human cell types. Moreover, Smart-seq3 showed a dramatic increase in sensitivity and typically detected thousands more genes per cell than Smart-seq2. Altogether, we developed a short-read sequencing strategy for single-cell RNA counting at isoform and allele-resolution applicable to large-scale characterization of cell types and states across tissues and organisms.