Transcriptomic and functional analysis of an autolysis-deficient, teicoplanin-resistant derivative of methicillin-resistant Staphylococcus aureus.

Details

Serval ID
serval:BIB_0BC508F2B8D4
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Transcriptomic and functional analysis of an autolysis-deficient, teicoplanin-resistant derivative of methicillin-resistant Staphylococcus aureus.
Journal
Antimicrobial Agents and Chemotherapy
Author(s)
Renzoni A., Barras C., François P., Charbonnier Y., Huggler E., Garzoni C., Kelley W.L., Majcherczyk P., Schrenzel J., Lew D.P., Vaudaux P.
ISSN
0066-4804[print], 0066-4804[linking]
Publication state
Published
Issued date
2006
Volume
50
Number
9
Pages
3048-3061
Language
english
Abstract
The molecular basis of glycopeptide-intermediate S. aureus (GISA) isolates is not well defined though frequently involves phenotypes such as thickened cell walls and decreased autolysis. We have exploited an isogenic pair of teicoplanin-susceptible (strain MRGR3) and teicoplanin-resistant (strain 14-4) methicillin-resistant S. aureus strains for detailed transcriptomic profiling and analysis of altered autolytic properties. Strain 14-4 displayed markedly deficient Triton X-100-triggered autolysis compared to its teicoplanin-susceptible parent, although microarray analysis paradoxically did not reveal significant reductions in expression levels of major autolytic genes atl, lytM, and lytN, except for sle1, which showed a slight decrease. The most important paradox was a more-than-twofold increase in expression of the cidABC operon in 14-4 compared to MRGR3, which was correlated with decreased expression of autolysis negative regulators lytSR and lrgAB. In contrast, the autolysis-deficient phenotype of 14-4 was correlated with both increased expression of negative autolysis regulators (arlRS, mgrA, and sarA) and decreased expression of positive regulators (agr RNAII and RNAIII). Quantitative bacteriolytic assays and zymographic analysis of concentrated culture supernatants showed a striking reduction in Atl-derived, extracellular bacteriolytic hydrolase activities in 14-4 compared to MRGR3. This observed difference was independent of the source of cell wall substrate (MRGR3 or 14-4) used for analysis. Collectively, our results suggest that altered autolytic properties in 14-4 are apparently not driven by significant changes in the transcription of key autolytic effectors. Instead, our analysis points to alternate regulatory mechanisms that impact autolysis effectors which may include changes in posttranscriptional processing or export.
Keywords
Bacteriolysis/genetics, Cell Wall/genetics, Extracellular Fluid/enzymology, Humans, Hydrolases/metabolism, Methicillin Resistance, Octoxynol, Oligonucleotide Array Sequence Analysis, Peptide Hydrolases/biosynthesis, Peptide Hydrolases/genetics, Staphylococcus aureus/drug effects, Staphylococcus aureus/genetics, Teicoplanin/pharmacology, Transcription, Genetic
Pubmed
Web of science
Open Access
Yes
Create date
24/01/2008 14:54
Last modification date
20/08/2019 13:33
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