Microbial Gimics: Strategies of Successful Pathogenicity by Staphylococcus aureus

AbstractStaphylococcus aureus is a major human pathogen and represents a clinical challenge because of widespread antibiotic resistance. Methicillin resistant Staphylococcus aureus (MRSA) is particularly problematic and originates by the horizontal acquisition of mecA encoding PBP2a, an extracellular membrane anchored transpeptidase, which confers resistance to β-lactam antibiotics by allosteric gating of its active site channel. Herein, we show that dual disruption of PrsA, a lipoprotein chaperone displaying anti-aggregation activity, together with HtrA1, a membrane anchored chaperone/serine protease, resulted in severe and synergistic attenuation of PBP2a folding that restores sensitivity to β-lactams such as oxacillin. Purified PBP2a has a pronounced unfolding transition initiating at physiological temperatures that leads to irreversible precipitation and complete loss of activity. The concordance of genetic and biochemical data highlights the necessity for extracellular protein folding factors governing MRSA β-lactam resistance. Targeting the PBP2a folding pathway represents a particularly attractive adjuvant strategy to combat antibiotic resistance.

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Synthesis, Characterization and Estimation the Biological Activity of New Mesomorphic Heterocyclic Compounds

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v10i1.24 ◽

2020 ◽

Vol 10 (01) ◽

pp. 106-113

Author(s):

Hussain A. Hamza ◽

Nasreen R. Jber

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Methicillin Resistant Staphylococcus Aureus ◽

High Titer ◽

Resistant Bacteria ◽

Skin Infections ◽

Promising Alternative ◽

Methicillin Resistant ◽

Phage Cocktail

Methicillin-resistant Staphylococcus aureus (MRSA) is a S. aureus that resistant to β-lactam antibiotics (e.g., Cefoxitin and Oxacillin). MRSA has a tremendous capacity to develop resistance to other classes of antibiotics and forming a real threat to patients. The process of exploring a new tactic of non-antibiotic treatments has become an urgent need. A bacteriophage is one of the possible treatments that strongly suggested. Bacteriophages are viruses that infect bacteria as a natural host with a bactericidal capability against multidrug-resistant bacteria that do not respond to conventional antibiotics. The current study investigates the lytic efficacy of phage-cocktail in vitro, specifically against S. aureus isolated from skin infections and find out the possible association of phage-antibiotic resistance. A total of 43 isolates of Methicillin-resistant staphylococcus aureus were isolated from skin infections. The isolates are distributed as (10 isolates of burn, 4 isolates of diabetic foot ulcer, 7 isolates of surgical wounds, 3 isolates of pressure ulcer, and 19 of skin and soft tissue infection). The isolates exhibited variant antibiotic susceptibility against 12 antibiotics (Cefoxitin FOX, Vancomycin VAN, Oxacillin OX, Rifampin RA, Chloramphenicol C, Nitrofurantoin F, Clindamycin DA, Azithromycin AZM, Amikacin AK, Trimethoprim-sulfamethoxazole SXT, Ciprofloxacin CIP, and Gentamicin CN). A bacteriophage cocktail was isolated using a phage-enrichment technique, high titer phage lysate (5*109 pfu/ml) was obtained and investigated against 43 MRSA isolates. The phage-cocktail showed high specificity to S. aureus but variable susceptibility to 43 MRSA isolates. It was observed that there was no association (p greater than 0.05) between phage and antibiotic resistance of (FOX, OX, VAN, RA, C, F, and DA) where the significant association was observed (p less than 0.05) with (AZM, AK, SXT, CIP, and CN). Significantly, the more antibiotic-resistant isolates exhibited more sensitivity to phage-cocktail, which represents a promising alternative to antibiotics that do not affect with increasing antibiotic resistance.

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Sistem Pakar Menggunakan Metode Case Based Reasoning dalam Akurasi Penyakit Disebabkan oleh Bakteri Staphylococcus Aureus

Jurnal Sistim Informasi dan Teknologi ◽

10.37034/jsisfotek.v3i1.94 ◽

2020 ◽

Author(s):

Surya Aulia Rahman ◽

S Sumijan

Keyword(s):

Staphylococcus Aureus ◽

Respiratory Infections ◽

Bacterial Disease ◽

Case Based Reasoning ◽

Skin Infections ◽

Highly Pathogenic ◽

Eye Infections ◽

Serious Infections ◽

Tract Infections ◽

Case Based

Staphylococcus aureus is the most worrisome bacteria in the world of health because it is highly pathogenic and can cause serious infections in previously healthy individuals. Staphylococcus aureus has gram-positive cells, round (cocci) 0.7-0.9 µm in diameter, non-spore-forming, non-motile, facultative anoerobes, in colony shaped like a grape string. This bacterial infection in humans varies in severity, from minor skin infections (furunculosis and impertigo), urinary tract infections, respiratory infections, to eye infections. This causes many patients to need an expert (doctor) to consult about the symptoms that a patient appears or experiences and the risk factors felt by the patient. So they conducted this research using the Case Based Reasoning (CBR) method which consists of 4 steps, namely retrieve, reuse, retain and revise. By using the case-based reasoning method for a problem with the staphylococcus aureus bacterial disease, it is easier for a patient to find treatment and a solution. With an expert system using this method (case based reasoning), experts (doctors) can easily find out what diseases are suffered by staphylococcus. That way, patients with staphylococcus disease are prepared to deal with the disease they are suffering from.

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ANTIBIOTIC RESISTANCE AND VIRULENCE DETERMINANTS IN STAPHYLOCOCCUS AUREUS ISOLATED IN CYSTIC FIBROSIS PATIENTS

Journal of Cystic Fibrosis ◽

10.1016/s1569-1993(08)60476-2 ◽

2008 ◽

Vol 7 ◽

pp. S2

Author(s):

S. Stefani ◽

V. Cafiso ◽

T. Bertuccio ◽

D. Spina ◽

V. Demelio ◽

...

Keyword(s):

Cystic Fibrosis ◽

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Virulence Determinants

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Evaluation of P1' substrate specificity of staphylococcal SplB protease.

Acta Biochimica Polonica ◽

10.18388/abp.2014_1937 ◽

2014 ◽

Vol 61 (1) ◽

Cited By ~ 5

Author(s):

Katarzyna Pustelny ◽

Natalia Stach ◽

Benedykt Wladyka ◽

Adam Dubin ◽

Grzegorz Dubin

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Substrate Specificity ◽

Kinetic Data ◽

Proteolytic Enzymes ◽

Physiological Role ◽

Human Pathogen ◽

Extracellular Proteases ◽

Hydrolysis Of

Staphylococcus aureus is a dangerous human pathogen characterized by growing antibiotic resistance. Virulence of S. aureus relies on a variety of secreted and cell surface associated virulence factors among which certain proteolytic enzymes play an important role. Amid staphylococcal extracellular proteases, those encoded by the spl operon remain poorly characterized, both in terms of enzymology and their physiological role. Initial data demonstrated that Spl proteases exhibit restricted substrate specificity. This study describes development of convenient protein FRET substrates for SplB protease and characterization of the substrate preference of the protease at the P1' position. Kinetic data on hydrolysis of a panel of substrates substituted at the said position is provided.

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Sistem Pakar Menggunakan Metode Case Based Reasoning dalam Akurasi Penyakit Disebabkan oleh Bakteri Staphylococcus Aureus

Jurnal Sistim Informasi dan Teknologi ◽

10.37034/jsisfotek.v3i1.38 ◽

2021 ◽

pp. 13-19

Author(s):

Surya Aulia Rahman ◽

S Sumijan

Keyword(s):

Staphylococcus Aureus ◽

Respiratory Infections ◽

Bacterial Disease ◽

Case Based Reasoning ◽

Skin Infections ◽

Highly Pathogenic ◽

Eye Infections ◽

Serious Infections ◽

Tract Infections ◽

Case Based

Staphylococcus aureus is the most worrisome bacteria in the world of health because it is highly pathogenic and can cause serious infections in previously healthy individuals. Staphylococcus aureus has gram-positive cells, round (cocci) 0.7-0.9 µm in diameter, non-spore-forming, non-motile, facultative anoerobes, in colony shaped like a grape string. This bacterial infection in humans varies in severity, from minor skin infections (furunculosis and impertigo), urinary tract infections, respiratory infections, to eye infections. This causes many patients to need an expert (doctor) to consult about the symptoms that a patient appears or experiences and the risk factors felt by the patient. So they conducted this research using the Case Based Reasoning (CBR) method which consists of 4 steps, namely retrieve, reuse, retain and revise. By using the case-based reasoning method for a problem with the staphylococcus aureus bacterial disease, it is easier for a patient to find treatment and a solution. With an expert system using this method (case based reasoning), experts (doctors) can easily find out what diseases are suffered by staphylococcus. That way, patients with staphylococcus disease are prepared to deal with the disease they are suffering from.

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Situation of antibiotic resistance in Bangladesh and its association with resistance genes for horizontal transfer

10.1101/2020.04.06.027391 ◽

2020 ◽

Author(s):

Kazi Sarjana Safain ◽

Golam Sarower Bhuyan ◽

Sadia Tasnim ◽

Saad Hassan Hasib ◽

Rosy Sultana ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Resistance Gene ◽

Respiratory Infections ◽

Pcr Amplification ◽

Salmonella Typhi ◽

Bacterial Strains ◽

Aminoglycoside Resistance ◽

E Coli ◽

Tertiary Hospitals

The study investigated the spectrum of antibiotic resistance and the associated genes for aminoglycoside, macrolide and ESBL class of antibiotics using clinical isolates. A total of 430 preserved bacterial strains (Acinetobacter baumannii, n= 20; Pseudomonas aeruginosa, n= 26; Klebsiella pneumoniae, n= 42; E. coli , n= 85; Staphylococcus aureus, n= 84; Salmonella Typhi, n= 82; Enterococcus spp., n= 27; Streptococcus pneumoniae, n= 36 and CNS, n = 28) were examined. The strains were isolated from patients admitted to various tertiary hospitals of Dhaka city between 2015 and 2019 with either acute respiratory infections, wound infections, typhoid fever or diarrhea. The isolates were reconfirmed by appropriate microbiological and biochemical methods. Antimicrobial susceptibility tests were done using Kirby–Bauer disk diffusion approach. PCR amplification using resistance gene-specific primers for aminoglycoside, macrolide and ESBL class of antibiotics was done and the amplified products were confirmed by Sanger sequencing. Of the total isolates, 53% came out as MDR with 96.6% of E. coli and 90% of Staphylococcus aureus. There was a year-wise gradual increase of MDR isolates from 2015-2018 and by 2019 the increase in MDR isolates became almost 2-fold compared to 2015. Among the five ESBL genes investigated, CTXM-1 came out as the most prevalent (63%) followed by NDM-1 (22%) and E. coli isolates were the predominant reservoir of these genes. ErmB (55%) was the most frequently detected macrolide resistance gene, whereas aac ( 6 ) -Ib (35.44%) was the most prevalent aminoglycoside resistance gene and these genes were most prevalent in E. coli and P. aeruginosa isolates, respectively. CTXM-1 and ErmB (16.66%) were the most frequent partners of coexistence followed by CTXM-1 and aac ( 3 ) -II.

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Phylogeny Characterization of Seb Gene Encoding Enterotoxins in Staphylococcus aureus Isolated from Raw Milk and Cheese

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v9i3.13 ◽

2019 ◽

Vol 9 (o3) ◽

Author(s):

Fatima N. Aziz ◽

Laith Abdul Hassan Mohammed-Jawad

Keyword(s):

Staphylococcus Aureus ◽

Food Poisoning ◽

Raw Milk ◽

Staphylococcal Enterotoxin B ◽

Human Pathogen ◽

Conventional Pcr ◽

Biochemical Tests ◽

Specific Primers ◽

Gene Encoding

Food poisoning due to the bacteria is a big global problem in economically and human's health. This problem refers to an illness which is due to infection or the toxin exists in nature and the food that use. Milk is considered a nutritious food because it contains proteins and vitamins. The aim of this study is to detect and phylogeny characterization of staphylococcal enterotoxin B gene (Seb). A total of 200 milk and cheese samples were screened. One hundred ten isolates of Staphylococcus aureus pre-confirmed using selective and differential media with biochemical tests. Genomic DNA was extracted from the isolates and the SEB gene detects using conventional PCR with specific primers. Three staphylococcus aureus isolates were found to be positive for Seb gene using PCR and confirmed by sequencing. Sequence homology showed variety range of identity starting from (100% to 38%). Phylogenetic tree analyses show that samples (6 and 5) are correlated with S. epidermidis. This study discovered that isolates (A6-RLQ and A5-RLQ) are significantly clustered in a group with non- human pathogen Staphylococcus agnetis.

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