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| Status |
Public on May 31, 2011 |
| Title |
Expression data from low fluid shear cultured Staphylococcus aureus |
| Platform organism |
Staphylococcus aureus |
| Sample organism |
Staphylococcus aureus subsp. aureus N315 |
| Experiment type |
Expression profiling by array
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| Summary |
The opportunistic pathogen, Staphylococcus aureus, encounters a wide variety of fluid shear levels within the human host, which may play a key role in dictating whether this organism adopts a commensal interaction with the host or transitions to cause disease. Using rotating-wall vessel bioreactors to create a physiologically-relevant, low fluid shear environment, S. aureus was evaluated for cellular responses that could impact its colonization and virulence. S. aureus cells grown in a low fluid shear environment initiated a novel attachment-independent biofilm phenotype and were completely encased in extracellular polymeric substances. Compared to controls, low-shear cultured cells displayed slower growth and repressed virulence characteristics, including decreased carotenoid production, increased susceptibility to oxidative stress, and reduced survival in whole blood. Transcriptional whole genome microarray profiling suggested alterations in metabolic pathways. Further genetic expression analysis revealed the down-regulation of the RNA chaperone Hfq, which parallels low fluid shear responses of certain Gram negative organisms. This is the first study to report an Hfq association to fluid shear in a Gram positive organism, suggesting an evolutionarily conserved response to fluid shear among structurally diverse prokaryotes. Collectively, our results suggest S. aureus responds to a low fluid shear environment by initiating a biofilm/colonization phenotype with diminished virulence characteristics, which could lead to insight into key factors influencing the divergence between infection and colonization during initial host pathogen interaction.
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| Overall design |
Genetic expression profiles of Staphylococcus aureus cultured under low fluid shear conditions was compared to control cultures of S. aureus which was cultured in identical hardware in an orientation disrupting the low fluid shear effect. Samples from the same date of culture were compared (control 21:low 21 and control 30: low 30). S. aureus was cultured for 20 hours in either the low fluid shear or control orientated rotating wall vessel (RWV) bioreactor at which point the cells were removed and RNA extracted. At 20 hours, both cultures were in the same stage of growth (stationary phase) and at this point phenotypic differences between control and low fluid shear cultures were noted.
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| Contributor(s) |
Castro SL, Nelman-Gonzalez M, Nicerson CA, Ott CM |
| Citation(s) |
21803898 |
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| Submission date |
Mar 21, 2011 |
| Last update date |
Oct 18, 2012 |
| Contact name |
Sarah L Castro |
| E-mail(s) |
slcastro@utmb.edu
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| Organization name |
University of Texas Medical Branch
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| Street address |
301 University Blvd
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| City |
Galveston |
| State/province |
TX |
| ZIP/Postal code |
77555 |
| Country |
USA |
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| Platforms (1) |
| GPL1339 |
[S_aureus] Affymetrix S. aureus Genome Array |
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| Samples (4)
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| GSM694254 |
control culture 20 hr, biological rep 1 |
| GSM694255 |
control culture 20 hr, biological rep 2 |
| GSM694256 |
low-shear culture 20 hr, biological rep 1 |
| GSM694257 |
low-shear culture 20 hr, biological rep 2 |
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| Relations |
| BioProject |
PRJNA139723 |
| Supplementary file |
Size |
Download |
File type/resource |
| GSE28077_RAW.tar |
5.8 Mb |
(http)(custom) |
TAR (of CEL, CHP) |
| Processed data included within Sample table |
| Processed data provided as supplementary file |
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