scholarly journals Transcriptional Profiling of XdrA, a New Regulator of spa Transcription in Staphylococcus aureus

2010 ◽  
Vol 192 (19) ◽  
pp. 5151-5164 ◽  
Author(s):  
N. McCallum ◽  
J. Hinds ◽  
M. Ender ◽  
B. Berger-Bächi ◽  
P. Stutzmann Meier
Keyword(s):  
Staphylococcus Aureus ◽  
Reporter Gene ◽  
Transcriptional Profiling ◽  
Protein A ◽  
Dna Binding Protein ◽  
Infection Process ◽  
Gene Fusions ◽  
Temporal Expression ◽  
Nested Deletions ◽  
Complex Regulatory Network

ABSTRACT Transcription of spa, encoding the virulence factor protein A in Staphylococcus aureus, is tightly controlled by a complex regulatory network, ensuring its temporal expression over growth and at appropriate stages of the infection process. Transcriptomic profiling of XdrA, a DNA-binding protein that is conserved in all S. aureus genomes and shares similarity with the XRE family of helix-turn-helix, antitoxin-like proteins, revealed it to be a previously unidentified activator of spa transcription. To assess how XdrA fits into the complex web of spa regulation, a series of regulatory mutants were constructed; consisting of single, double, triple, and quadruple mutants lacking XdrA and/or the three key regulators previously shown to influence spa transcription directly (SarS, SarA, and RNAIII). A series of lacZ reporter gene fusions containing nested deletions of the spa promoter identified regions influenced by XdrA and the other three regulators. XdrA had almost as strong an activating effect on spa as SarS and acted on the same spa operator regions as SarS, or closely overlapping regions. All data from microarrays, Northern and Western blot analyses, and reporter gene fusion experiments indicated that XdrA is a major activator of spa expression that appears to act directly on the spa promoter and not through previously characterized regulators.

scholarly journals Transcriptional Profiling of Target of RNAIII-Activating Protein, a Master Regulator of Staphylococcal Virulence

2005 ◽  
Vol 73 (10) ◽  
pp. 6220-6228 ◽  
Author(s):  
Moshe Korem ◽  
Yael Gov ◽  
Madanahally D. Kiran ◽  
Naomi Balaban
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factors ◽  
Transcriptional Profiling ◽  
Protein A ◽  
Cell Communication ◽  
Global Regulator ◽  
Positive Bacterium ◽  
Master Regulator ◽  
Expression Of Genes ◽  
Histidine Phosphorylation

ABSTRACT Staphylococcus aureus is a gram-positive bacterium that is part of the normal healthy flora but that can become virulent and cause infections by producing biofilms and toxins. The production of virulence factors is regulated by cell-cell communication (quorum sensing) through the histidine phosphorylation of target of RNAIII-activating protein (TRAP), which is a 21-kDa protein that is highly conserved among staphylococci. Using microarray analysis, we show here that the expression and phosphorylation of TRAP upregulate the expression of most, if not all, toxins known to date, as well as their global regulator agr. In addition, we show here that the expression and phosphorylation of TRAP are also necessary for the expression of genes known to be necessary for the survival of the bacteria in a biofilm, like arc, pyr, and ure. TRAP is thus demonstrated to be a master regulator of staphylococcal pathogenesis.

scholarly journals SarZ Promotes the Expression of Virulence Factors and Represses Biofilm Formation by Modulating SarA and agr in Staphylococcus aureus

2008 ◽  
Vol 77 (1) ◽  
pp. 419-428 ◽  
Author(s):  
Sandeep Tamber ◽  
Ambrose L. Cheung
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Target Genes ◽  
Protein A ◽  
Dna Binding Protein ◽  
Normal Flora ◽  
Regulatory Pathways ◽  
Downstream Target ◽  
Alpha Hemolysin ◽  
Important Regulator

ABSTRACT Staphylococcus aureus is a remarkably adaptable organism capable of multiple modes of growth in the human host, as a part of the normal flora, as a pathogen, or as a biofilm. Many of the regulatory pathways governing these modes of growth are centered on the activities of two regulatory molecules, the DNA binding protein SarA and the regulatory RNAIII effector molecule of the agr system. Here, we describe the modulation of these regulators and their downstream target genes by SarZ, a member of the SarA/MarR family of transcriptional regulators. Transcriptional and phenotypic analyses of a sarZ mutant demonstrated that the decreased transcription of mgrA and the agr RNAIII molecule was accompanied by increased transcription of spa (protein A) and downregulation of hla (alpha-hemolysin) and sspA (V8 protease) transcripts when compared to its isogenic parent. The decrease in protease activity was also associated with an increase in SarA expression. Consistent with an increase in SarA levels, the sarZ mutant displayed an enhanced ability to form biofilms. Together, our results indicate that SarZ may be an important regulator governing the dissemination phase of S. aureus infections, as it promotes toxin expression while repressing factors required for biofilm formation.

Detection of Rabies Virus and Its Antibodies Using Staphylococcus aureus Protein A

2015 ◽  
Vol 43 (1) ◽  
pp. 87-93
Author(s):  
Hemmat A ◽  
A Albehwar ◽  
M Shendy
Keyword(s):  
Staphylococcus Aureus ◽  
Rabies Virus ◽  
Protein A

scholarly journals Virulence Factors Found in Nasal Colonization and Infection of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates and Their Ability to Form a Biofilm

Toxins ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 14
Author(s):  
Thamiris Santana Machado ◽  
Felipe Ramos Pinheiro ◽  
Lialyz Soares Pereira Andre ◽  
Renata Freire Alves Pereira ◽  
Reginaldo Fernandes Correa ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Sccmec Type ◽  
Protein A ◽  
Invasive Infection ◽  
Type I ◽  
Methicillin Resistant ◽  
Type Iv ◽  
Spa Gene ◽  
The City

Hospitalizations related to Methicillin-resistant Staphylococcus aureus (MRSA) are frequent, increasing mortality and health costs. In this way, this study aimed to compare the genotypic and phenotypic characteristics of MRSA isolates that colonize and infect patients seen at two hospitals in the city of Niterói—Rio de Janeiro, Brazil. A total of 147 samples collected between March 2013 and December 2015 were phenotyped and genotyped to identify the protein A (SPA) gene, the mec staphylococcal chromosomal cassette (SCCmec), mecA, Panton-Valentine Leucocidin (PVL), icaC, icaR, ACME, and hla virulence genes. The strength of biofilm formation has also been exploited. The prevalence of SCCmec type IV (77.1%) was observed in the colonization group; however, in the invasive infection group, SCCmec type II was prevalent (62.9%). The Multilocus Sequence Typing (MLST), ST5/ST30, and ST5/ST239 analyses were the most frequent clones in colonization, and invasive infection isolates, respectively. Among the isolates selected to assess the ability to form a biofilm, 51.06% were classified as strong biofilm builders. Surprisingly, we observed that isolates other than the Brazilian Epidemic Clone (BEC) have appeared in Brazilian hospitals. The virulence profile has changed among these isolates since the ACME type I and II genes were also identified in this collection.

scholarly journals Malonyl-proteome profiles of Staphylococcus aureus reveal lysine malonylation modification in enzymes involved in energy metabolism

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Yanan Shi ◽  
Jingjing Zhu ◽  
Yan Xu ◽  
Xiaozhao Tang ◽  
Zushun Yang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Energy Metabolism ◽  
Active Sites ◽  
Current Knowledge ◽  
Tricarboxylic Acid Cycle ◽  
Protein A ◽  
Pentose Phosphate ◽  
Post Translational Modification ◽  
Bacterial Physiology ◽  
Dihydrolipoyl Dehydrogenase

Abstract Background Protein lysine malonylation, a novel post-translational modification (PTM), has been recently linked with energy metabolism in bacteria. Staphylococcus aureus is the third most important foodborne pathogen worldwide. Nonetheless, substrates and biological roles of malonylation are still poorly understood in this pathogen. Results Using anti-malonyl-lysine antibody enrichment and high-resolution LC-MS/MS analysis, 440 lysine-malonylated sites were identified in 281 proteins of S. aureus strain. The frequency of valine in position − 1 and alanine at + 2 and + 4 positions was high. KEGG pathway analysis showed that six categories were highly enriched, including ribosome, glycolysis/gluconeogenesis, pentose phosphate pathway (PPP), tricarboxylic acid cycle (TCA), valine, leucine, isoleucine degradation, and aminoacyl-tRNA biosynthesis. In total, 31 malonylated sites in S. aureus shared homology with lysine-malonylated sites previously identified in E. coli, indicating malonylated proteins are highly conserved among bacteria. Key rate-limiting enzymes in central carbon metabolic pathways were also found to be malonylated in S. aureus, namely pyruvate kinase (PYK), 6-phosphofructokinase, phosphoglycerate kinase, dihydrolipoyl dehydrogenase, and F1F0-ATP synthase. Notably, malonylation sites were found at or near protein active sites, including KH domain protein, thioredoxin, alanine dehydrogenase (ALD), dihydrolipoyl dehydrogenase (LpdA), pyruvate oxidase CidC, and catabolite control protein A (CcpA), thus suggesting that lysine malonylation may affect the activity of such enzymes. Conclusions Data presented herein expand the current knowledge on lysine malonylation in prokaryotes and indicate the potential roles of protein malonylation in bacterial physiology and metabolism.

Protein A of Staphylococcus aureus strain NCTC8325 interacted with heparin

2021 ◽  
Author(s):  
Hui Shi ◽  
Jiaqin Tang ◽  
Cuiying An ◽  
Lingkang Yang ◽  
Xianxuan Zhou
Keyword(s):  
Staphylococcus Aureus ◽  
Protein A ◽  
Aureus Strain
Sign in / Sign up

Export Citation Format

Share Document