Multiple PCR for Detection of Genes Encoding Antibiotic Resistance in Staphylococcus aureus

Abstract Cystic fibrosis (CF) is the most common life-threatening genetic disease among Caucasians. CF patients suffer from chronic lung infections due to the presence of thick mucus, caused by cftr gene dysfunction. The two most commonly found bacteria in the mucus of CF patients are Staphylococcus aureus and Pseudomonas aeruginosa. It is well known that early-infecting P. aeruginosa strains produce anti-staphylococcal compounds and inhibit S. aureus growth. More recently, it has been shown that late-infecting P. aeruginosa strains develop commensal-like/coexistence interaction with S. aureus. The aim of this study was to decipher the impact of P. aeruginosa strains on S. aureus. RNA sequencing analysis showed 77 genes were specifically dysregulated in the context of competition and 140 genes in the context of coexistence in the presence of P. aeruginosa. In coexistence, genes encoding virulence factors and proteins involved in carbohydrates, lipids, nucleotides and amino acids metabolism were downregulated. On the contrary, several transporter family encoding genes were upregulated. In particular, several antibiotic pumps belonging to the Nor family were upregulated: tet38, norA and norC, leading to an increase in antibiotic resistance of S. aureus when exposed to tetracycline and ciprofloxacin and an enhanced internalization rate within epithelial pulmonary cells. This study shows that coexistence with P. aeruginosa affects the S. aureus transcriptome and virulence.

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Going through phages: A Computational approach to Revealing the role of prophage in Staphylococcus aureus

10.1101/2021.11.10.468171 ◽

2021 ◽

Author(s):

Tyrome Steven Sweet ◽

Suzanne Sindi ◽

Mark Sistrom

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Genome Evolution ◽

Virulence Factors ◽

Rapid Growth ◽

Computational Approach ◽

Computational Pipeline ◽

Genes Encoding

Prophages have important roles in virulence, antibiotic resistance and genome evolution in Staphylococcus aureus. Rapid growth in the number of sequenced S. aureus genomes allows for an investigation of prophage sequences in S. aureus at an unprecedented scale. We developed a computational pipeline to detect and analyze prophage sequences in nearly 10,011 S. aureus genomes, discovering thousands of putative prophage sequences with genes encoding virulence factors and antibiotic resistance.

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Structural analysis of avibactam-mediated activation of the bla and mec divergons in methicillin-resistant Staphylococcus aureus

Journal of Biological Chemistry ◽

10.1074/jbc.ra120.013029 ◽

2020 ◽

Vol 295 (32) ◽

pp. 10870-10884 ◽

Cited By ~ 2

Author(s):

J. Andrew N. Alexander ◽

Mariia Radaeva ◽

Dustin T. King ◽

Henry F. Chambers ◽

Artem Cherkasov ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Physiological Role ◽

Antibiotic Resistance Genes ◽

Binding Pocket ◽

Methicillin Resistant ◽

Mortality And Morbidity ◽

Expression Of Genes ◽

Genes Encoding

Methicillin-resistant Staphylococcus aureus (MRSA) infections cause significant mortality and morbidity globally. MRSA resistance to β-lactam antibiotics is mediated by two divergons that control levels of a β-lactamase, PC1, and a penicillin-binding protein poorly acylated by β-lactam antibiotics, PBP2a. Expression of genes encoding these proteins is controlled by two integral membrane proteins, BlaR1 and MecR1, which both have an extracellular β-lactam–binding sensor domain. Here, we solved the X-ray crystallographic structures of the BlaR1 and MecR1 sensor domains in complex with avibactam, a diazabicyclooctane β-lactamase inhibitor at 1.6–2.0 Å resolution. Additionally, we show that S. aureus SF8300, a clinically relevant strain from the USA300 clone of MRSA, responds to avibactam by up-regulating the expression of the blaZ and pbp2a antibiotic-resistance genes, encoding PC1 and PBP2a, respectively. The BlaR1–avibactam structure of the carbamoyl-enzyme intermediate revealed that avibactam is bound to the active-site serine in two orientations ∼180° to each other. Although a physiological role of the observed alternative pose remains to be validated, our structural results hint at the presence of a secondary sulfate-binding pocket that could be exploited in the design of future inhibitors of BlaR1/MecR1 sensor domains or the structurally similar class D β-lactamases. The MecR1–avibactam structure adopted a singular avibactam orientation similar to one of the two states observed in the BlaR1–avibactam structure. Given avibactam up-regulates expression of blaZ and pbp2a antibiotic resistance genes, we suggest further consideration and research is needed to explore what effects administering β-lactam–avibactam combinations have on treating MRSA infections.

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Genotypic Molecular Detection of Certain Genes Encoding Virulence Determinates and Antibiotic Resistance in Staphylococcus Aureus Isolates from Mastitis Cows

Alexandria Journal of Veterinary Sciences ◽

10.5455/ajvs.230403 ◽

2017 ◽

pp. 1

Author(s):

Ahmedc AlAshmony

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Molecular Detection ◽

Genes Encoding

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Investigation of the antibiotic resistance prevalence and genes encoding exfoliative toxins of Staphylococcus aureus isolated from Pasteur institude HCMC

Science and Technology Development Journal ◽

10.32508/stdj.v19i2.755 ◽

2016 ◽

Vol 19 (2) ◽

pp. 15-23

Author(s):

Trang Nu Dai Phan ◽

Lan Le Ngoc Vu ◽

Ninh Nguyen Duc Uong ◽

Nghia Huu Cao

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Methicillin Resistant Staphylococcus Aureus ◽

Disease Gene ◽

Specific Detection ◽

Genes Encoding ◽

Mrsa Strains ◽

Clinical Biology ◽

The Relationship ◽

Infants And Young Children

Exfoliative toxins (ETs), the toxin caused the dangerous Staphylococcal scalded skin syndrome (SSSS), mainly affect on infants and young children [1]. By examining the ratio of antibiotic resistance and the detection of rate eta, etb genes encoding ETs toxins that cause disease in the group of Staphylococcus aureus (S. aureus), we would like to draw conclusions about the relationship between the disease gene with the antibiotic resistance of S. aureus thereby affording an appropriate choice of antibiotic to physicians, reduce the risk of spreading Methicillin resistant Staphylococcus aureus (MRSA) strains present in the community. In this study, we determine antibiotic susceptibility of S. aureus by Kirby-Bauer method on 293 S. aureus isolates from clinical specimens at the Department of Clinical Biology, Pasteur Institute HCMC. In total 293 S. aureus strains studied, we identified 49.7 % of MRSA strains the conduction PCR with primers specific detection of eta, etb gene that encoding toxins ETs applying on 118 strains S. aureus, discovered 4/118 (3.4 %) S. aureus trains carrying the gene eta, 1/118 (0.8 %) S. aureus trains carrying the gene etb. Because of the small presence of S. aureus strains carrying the genes encoding ETs the relationship between the gene for ET toxins and antibiotic resistance in S. aureus was not clearly defined.

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The Thymidine-Dependent Small-Colony-Variant Phenotype Is Associated with Hypermutability and Antibiotic Resistance in Clinical Staphylococcus aureus Isolates

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01395-07 ◽

2008 ◽

Vol 52 (6) ◽

pp. 2183-2189 ◽

Cited By ~ 52

Author(s):

Silke Besier ◽

Johannes Zander ◽

Barbara C. Kahl ◽

Peter Kraiczy ◽

Volker Brade ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

23S Rrna ◽

Beta Lactam ◽

Small Colony Variant ◽

Dna Mismatch ◽

Beta Lactam Antibiotics ◽

Genes Encoding ◽

Small Colony ◽

Morphological Variants

ABSTRACT Thymidine-dependent small-colony variants (TD-SCVs) of Staphylococcus aureus can be isolated from the airway secretions of patients suffering from cystic fibrosis (CF) and are implicated in persistent and treatment-resistant infections. These characteristics, as well as the variety of mutations in the thymidylate synthase-encoding thyA gene which are responsible for thymidine dependency, suggest that these morphological variants are hypermutable. To prove this hypothesis, we analyzed the mutator phenotype of different S. aureus phenotypes, in particular CF-derived TD-SCVs, CF-derived isolates with a normal phenotype (NCVs), and non-CF NCVs. The comparative analysis revealed that the CF isolates had significantly higher mutation rates than the non-CF isolates. The TD-SCVs, in turn, harbored significantly more strong hypermutators (mutation rate ≥ 10−7) than the CF and non-CF NCVs. In addition, antimicrobial resistance to non-beta-lactam antibiotics, including gentamicin, ciprofloxacin, erythromycin, fosfomycin, and rifampin, was significantly more prevalent in TD-SCVs than in CF and non-CF NCVs. Interestingly, macrolide resistance, which is usually mediated by mobile genetic elements, was conferred in half of the macrolide-resistant TD-SCVs by the point mutation A2058G or A2058T in the genes encoding the 23S rRNA. Sequence analysis of mutS and mutL, which are involved in DNA mismatch repair in gram-positive bacteria, revealed that in hypermutable CF isolates and especially in TD-SCVs, mutL was often truncated due to frameshift mutations. In conclusion, these data provide direct evidence that TD-SCVs are hypermutators. This hypermutability apparently favors the acquisition of antibiotic resistance and facilitates bacterial adaptation during long-term persistence.

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Coexistence with Pseudomonas aeruginosa alters Staphylococcus aureus transcriptome, antibiotic resistance and internalization into epithelial cells

10.1101/775684 ◽

2019 ◽

Author(s):

Paul Briaud ◽

Laura Camus ◽

Sylvère Bastien ◽

Anne Doléans-Jordheim ◽

François Vandenesch ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibiotic Resistance ◽

Sequencing Analysis ◽

Common Life ◽

Transporter Family ◽

Genes Encoding ◽

Life Threatening ◽

Internalization Rate ◽

The Impact

ABSTRACTCystic fibrosis (CF) is the most common life-threatening genetic disease among Caucasians. CF patients suffer from chronic lung infections due to the presence of thick mucus, caused by cftr gene dysfunction. The two most commonly found bacteria in the mucus of CF patients are Staphylococcus aureus and Pseudomonas aeruginosa. It is well known that early-infecting P. aeruginosa strains produce anti-staphylococcal compounds and inhibit S. aureus growth. More recently, it has been shown that late-infecting P. aeruginosa strains develop commensal-like/coexistence interaction with S. aureus. The aim of this study was to decipher the impact of P. aeruginosa strains on S. aureus. RNA sequencing analysis showed 77 genes were specifically dysregulated in the context of competition and 140 genes in the context of coexistence in the presence of P. aeruginosa. In coexistence, genes encoding virulence factors and proteins involved in carbohydrates, lipids, nucleotides and amino acids metabolism were downregulated. On the contrary, several transporter family encoding genes were upregulated. In particular, several antibiotic pumps belonging to the Nor family were upregulated: tet38, norA and norC, leading to an increase in antibiotic resistance of S. aureus when exposed to tetracycline and ciprofloxacin and an enhanced internalization rate within epithelial pulmonary cells. This study shows that coexistence with P. aeruginosa affects the S. aureus transcriptome and virulence.

Download Full-text