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Series GSE102637 Query DataSets for GSE102637
Status Public on Aug 14, 2019
Title Colonizing and infecting subclones diverge during Staphylococcus aureus infection
Organism Staphylococcus aureus
Experiment type Expression profiling by high throughput sequencing
Summary Therapy of Staphylococcus aureus bacteremia is often ineffective, even under optimal conditions, and adapted subclones with attenuated agr-mediated virulence activation are associated with persistent infection and mortality. To understand how apparent loss of virulence leads to increased mortality, we sequenced complete genomes from clone pairs from colonizing and infected sites of patients in whom S. aureus demonstrated a within-host downshift in agr function in the infecting isolate. Clone pairs with a downshift in agr function showed substantial genetic divergence compared to wild-type pairs from controls. Complementation studies further identified an agr-defective bacteremic strain that was highly virulent in vivo, which we linked to a mutation that restored expression of the agr-regulated ess/Type-VII secretion system; a known virulence factor. Our results suggest that selection pressure during invasive infection is strong enough to mutationally bypass agr-deficiency associated loss of virulence, and that efforts to suppress agr function may need to be reconsidered.
 
Overall design Clonal S. aureus isolates from colonizing (nares) and infecting sites (blood) were obtained from a single patient. Whole-genome comparisons of single colonies from both isolates revealed 361 genetic variants between strain genomes, including a loss of agr functionality in the blood strain. To assess the impact of non-agr mutations engineered an agr knockout of the wild-type nares strain and complemented the naturally occurring agr mutant blood strain. Wild-type agr genes were transduced in single copy to the naturally occurring agr-defective variant using the staphylococcal pathogenicity island (SaPI)-1 attC locus as the insertion site. The four different strains were then grown to late log (OD600 of ~0.8) and profiled by directional RNA-Seq, in duplicate.
 
Contributor(s) Altman DR, Sullivan MJ, Chacko KI, Balasubramanian D, Pak TR, Sause WE, Kumar K, Sebra R, Deikus G, Attie O, Rose H, Lewis M, Fulmer Y, Bashir A, Kasarskis A, Schadt EE, Richardson AR, Torres VJ, Shopsin B, van Bakel H
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BioProject PRJNA393749
Submission date Aug 14, 2017
Last update date Jul 25, 2021
Contact name Kieran Ifan Chacko
E-mail(s) kieran.chacko@icahn.mssm.edu
Organization name Icahn School of Medicine at Mount Sinai
Department Genetic & Genomic Sciences
Street address One Gustave L. Levy Place
City New York
State/province NY
ZIP/Postal code 10029
Country USA
 
Platforms (1)
GPL19006 Illumina HiSeq 2500 (Staphylococcus aureus)
Samples (8)
GSM2742087 Wild-type agr-deficient blood strain, replicate A
GSM2742088 Agr complemented blood strain, replicate A
GSM2742089 Wild-type agr-deficient blood strain, replicate B
Relations
SRA SRP218276

Download family Format
SOFT formatted family file(s) SOFTHelp
MINiML formatted family file(s) MINiMLHelp
Series Matrix File(s) TXTHelp

Supplementary file Size Download File type/resource
GSE102637_PS00089_1A_ilm_prokka.fna.gz 848.0 Kb (ftp)(http) FNA
GSE102637_PS00089_1A_ilm_prokka.gtf.gz 94.3 Kb (ftp)(http) GTF
GSE102637_RAW.tar 190.0 Kb (http)(custom) TAR (of TXT)
SRA Run SelectorHelp
Raw data provided as supplementary file
Processed data provided as supplementary file

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