Phenotypic Determination of Biofilm Formation and Acquired Resistance Profile of Clinically-Derived Bacterial Isolates

Infections caused by biofilm forming bacteria is of major public health concern because of its association with multi-resistance to antimicrobial drugs and host defenses, leading to chronic and recurrent infections. Here, using Congo red agar method, Kirby-bauer disk diffusion technique and the consensus criteria of the European Centre for Disease Control (ECDC) and Centre for Disease Control (CDC), we determined the acquired resistance profile of biofilm producing phenotypes of clinically derived bacteria, classified as Multidrug resistant (MDR), extensively drug resistant (XDR) and Pandrug resistant (PDR). Fifty (50) de-identified bacterial isolates, comprising of five different species (Staphylococcus aureus, Escherichia coli, Proteus spp, Klebsiella pneumoniae and Pseudomonas aeruginosa) were sampled for the study. 64.0% of these isolates were observed to produce biofilms. Isolates recovered from urine samples (50.0%) were the most significant biofilm producers, chief among which was Staphylococcus aureus (15.6%) (X2=0.52; p<.05; P=0.9714). 78.0% of the biofilm producing phenotypes were atleast multidrug resistant (31.4% MDR; 31.4% XDR; 15.7% PDR) (f= 0.40678; df=3; p<.05; P=0.7502). Extreme forms of acquired resistance (XDR and PDR) was more pronounced among biofilm producing strains than the non-biofilm producing strains, and was statistically significant (f=5.0; p=.026336; df=14; p<.05). All Staphylococcus aureus and Pseudomonas aeruginosa isolates were atleast multidrug resistant, with the biofilm producing strains of the latter being completely resistant to Gentamicin and Ciprofloxacin. As such, it can be deduced that resistance to multiple antimicrobial drugs is more pronounced among biofilm producing phenotypes of clinically derived bacterial isolates.

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Co-existence of LasI, RhI, and Pseudomonas Quinolone Signal Quorum-sensing Genes in Clinical Pseudomonas aeruginosa Isolates

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.10.3.5 ◽

2020 ◽

Vol 10 (03) ◽

pp. 337-343

Author(s):

Anwer J. Faisal ◽

Munim Radwan Ali ◽

Layla Abdulhamid Said

Keyword(s):

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Antimicrobial Agents ◽

Multidrug Resistant ◽

Antibiotics Resistance ◽

Bacterial Isolates ◽

Antimicrobial Drugs ◽

Physiological Processes ◽

Pseudomonas Quinolone Signal ◽

Production Pattern

Pseudomonas aeruginosa can regulate different group actives and physiological processes through the quorum sensing mechanism. The aims of this research were to detect the presence of quorum sensing genes in 50 clinical P. aeruginosa isolates, which represent by (lasI, lasR, rhlI, and rhlR) and Pseudomonas quinolone signal (PQS) (PgsA, PgsB, PgsC, PgsD, PgsE, and MvfR) genes by Polymerase chain reaction (PCR) technique and interaction between the two systems. Isolates were subjected to test their susceptibility to 12 antimicrobial drugs, 64% of isolates showed resistance to ceftazidime, followed by carbencillin (56%), while only 8% were resistant to imipenem. In addition, all of the bacterial isolates were distributed within three multidrug-resistant (MDR) patterns, viz., A, B, and C. The highest rate of MDR was showed with MDR pattern C, in which bacterial isolates showed resistance to resist (9→11) antimicrobial drugs. Results revealed that P. aeruginosa isolates have different gene patterns, viz., A to E. According to quorum sensing genes production, pattern A found to express all the genes in LasI, RhI, and PQS system, while pattern B has a defective for the production of lasR, rhlR genes, while the same isolates have the PQS system all present. Significantly, there is a positive relationship between las and rhl system and regulation of antibiotics resistance, in which the bacterial isolates that have las and rhl genes showed high resistance to common antimicrobial agents under study. These findings suggest that PQS can function as an intercellular signal in P. aeruginosa that is not restricted only to alkyl homoserine lactones (AHL).

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Antibacterial Activity of Aloe vera Gel against Multidrug Resistant Staphylococcus aureus and Pseudomonas aeruginosa

UMYU Journal of Microbiology Research (UJMR) ◽

10.47430/ujmr.2052.009 ◽

2020 ◽

pp. 74-80

Author(s):

Usman A. ◽

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Wound Infection ◽

Aloe Vera ◽

Multidrug Resistant ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Diffusion Technique ◽

Aloe Vera Gel

Staphylococcus aureus and Pseudomonas aeruginosa have been implicated as important nosocomial pathogens causing severe infections especially in hospitalized patients. The aim of the study was to assess the antibacterial activity of Aloe vera gel against multidrug resistant S. aureus and P. aeruginosa isolated from wound. Clinical isolates of S. aureus and P. aeruginosa from wound infection were collected from Microbiology laboratory of Barau Dikko Teaching Hospital (BDTH), Kaduna and re-confirmed using standard microbiological procedure. Antibiotic susceptibility pattern of the isolates was determined using Kirby Bauer disk diffusion method. Aloe vera gel was obtained fresh matured leaves of Aloe vera plant and was screened for the presence of phytochemical constituents. Antibacterial activity of the Aloe vera gel against Multidrug Resistant (MDR) Staphylococcus aureus and Pseudomonas aeruginosa isolates was determined by agar well diffusion technique. The result revealed that all the two isolates were resistant to more than three classes of antibiotics. The Staphylococcus aureus isolate was resistant to fluoroquinolone (ciprofloxacin), aminoglycoside (gentamicin), cephalosporin (cefaroline), folate pathway antagonist (trimethoprim-sulfamethoxazole), penicillin(cefoxitin) and macrolide (erythromycin) while the Pseudomonas aeruginosa isolate was resistant to βlactam (ticarcillin-clavulanate), fluoroquinolone (ciprofloxacin and norfloxacin), aminoglycoside (gentamicin) and cephalosporin (ceftazidime)hence regarded as MDR isolates. Phytochemical screening of the gel revealed the presence of saponins, flavonoids, terpenoids and alkaloids. The Aloe vera gel was found to have antibacterial activity against the test isolates with MIC and MBC values of 25µg/mL and 50µg/mL against MDR S. aureus 50µg/mL and 100µg/mL against MDR P. aeruginosa respectively. The study identified that Aloe vera gel possesses antibacterial activity against MDR S. aureus and P. aeruginosa isolated from wound infection. Keywords: Aloe vera gel, Staphylococcus aureus, Pseudomonas aeruginosa, antibacterial, MDR

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A quest to the therapeutic arsenal: Novel strategies to combat multidrug-resistant bacteria

Current Gene Therapy ◽

10.2174/1566523221666210419084836 ◽

2021 ◽

Vol 21 ◽

Author(s):

Priyanka Ashwath ◽

Akhila Dharnappa Sannejal

Keyword(s):

Multidrug Resistant ◽

Health Concern ◽

Resistant Bacteria ◽

Drug Resistant ◽

Antimicrobial Drugs ◽

Short Palindromic Repeat ◽

Prevention Of Infections ◽

Resistant Bacterial Strain ◽

Conventional Antibiotics ◽

Drug Resistant Strains

: The increasing resistance of the disease-causing pathogens to antimicrobial drugs is a public health concern and a socio-economic burden. The emergence of multi-drug resistant strains has made it harder to treat and combat infectious diseases with available conventional antibiotics. There are currently few effective therapeutic regimens for the successful prevention of infections caused by drug-resistant microbes. The various alternative strategies used in the recent past to decrease and limit antibiotic resistance in pathogens include bacteriophages, vaccines, anti-biofilm peptides, and antimicrobial peptides. However, in this review, we focus on the novel and robust molecular approach of antisense RNA (asRNA) technology and the clustered regulatory interspaced short palindromic repeat (CRISPR)-based antibiotic therapy, which can be exploited to selectively eradicate the drug-resistant bacterial strain in a sequence-specific fashion establishing opportunities in the treatment of multi-drug resistant related infections.

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Anti-methicillin resistant Staphylococcus aureus (MRSA) activity of an acetone extract from the leaves of Canarium odontophyllum (Miq.)

The Journal of Phytopharmacology ◽

10.31254/phyto.2018.7301 ◽

2018 ◽

Vol 7 (3) ◽

pp. 225-229

Author(s):

Nur Amira Mohd Shamsuddin ◽

◽

Dayang Fredalina Basri ◽

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Acetone Extract ◽

Health Concern ◽

Antimicrobial Drugs ◽

Methicillin Resistant ◽

Bacteriostatic Action ◽

Broth Microdilution Method ◽

Canarium Odontophyllum ◽

Time Kill

Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern that has caused nosocomial and community infections over the past decade. The emergence of multi-drug resistant strains and limitations of present antimicrobial drugs have led to continuous search for natural products as curative agents for MRSA infections. Canarium odontophyllum Miq., locally known as dabai, has been considered an alternative phytotherapeutic treatment for MRSA. The aim of this study was to evaluate the bacteriostatic activity of an acetone extract from C. odontophyllum leaves against MRSA. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract against the ATCC 33591 and Mu50 strains were determined using the broth microdilution method, and a time-kill assay was employed to assess the type of bacteriostatic action of the extract against the Mu50 strain only. The MIC and MBC values of the extract against Mu50 were 312.5 µg/ml and 625 µg/ml, respectively, whereas the MIC and MBC values for ATCC 33591 were 625 µg/ml and 1,250 µg/ml, respectively, confirming the bacteriostatic effect against both MRSA strains. A time-kill assay showed that the acetone extract of C. odontophyllum leaves exhibited concentrationdependent bacteriostatic action against the Mu50 strain at 1/2× MIC, 1× MIC and 2× MIC. However, the extract was bactericidal only at the highest concentration (4× MIC) with a reduction in cell viability of more than 3 log10 within 24 hours. These findings confirm that an acetone extract from C. odontophyllum leaves inhibited growth of MRSA at low concentration and could be utilised as an alternative anti-MRSA agent in immune uncompromised hosts

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Characterisation of Plasmids in Multidrug Resistant Uropathogenic Gram-negative Bacterial Isolates

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2021/48356.14950 ◽

2021 ◽

Author(s):

Manish Ranjan ◽

Mahadevan Kumar ◽

Sourav Sen ◽

Parijat Das ◽

Kunal Kanti Lahiri

Keyword(s):

Acquired Resistance ◽

Multidrug Resistant ◽

Cross Sectional Study ◽

Bacterial Isolates ◽

Cross Sectional ◽

Gram Negative ◽

Hospital Stays ◽

Tract Infections ◽

Almost All ◽

Prolonged Hospital

Introduction: Urinary Tract Infections (UTI) are one of the commonest conditions for which people seek medical care with an estimated 150 million episodes per annum worldwide. An unprecedented upsurge in the rate of development of antimicrobial resistance has reduced the therapeutic options leading to increased morbidity, prolonged hospital stays, development of complications. Majority of these infections are attributable to Gram negative bacteria which have now acquired resistance to almost all classes of antibiotics. Aim: To analyse the plasmid-mediated drug resistance and characterise the major plasmid families that are in circulation. Materials and Methods: A cross-sectional study comprising of a total of 95 non consecutive multidrug-resistant gram-negative bacterial isolates were subjected to Plasmid based replicon typing from January 2017 to June 2018. The 18 major replicons were divided in five multiplex and three uniplex Polymerase Chain Reaction (PCR) formats and the samples were subjected for plasmid characterisation and further sequencing of the plasmid Deoxyribonucleic Acid (DNA). The data obtained was analysed by Microsoft Excel software. Results: Escherichia coli, accounted for maximum n=51 (53.7%), Klebsiella pneumoniae n=19 (20%), Citrobacter sp n=11 (11.6%), miscellaneous gram negative n=14 (14.7%) The isolates exhibited a high degree of resistance to almost all tested antibiotics, sparing a few like Fosfomycin, Chloramphenicol, Imipenem, Amikacin. A total of 154 different plasmid families were detected from the 95 isolates. FIB replicon (24%), FIA (21%), F, W (20%), FIC, B/O (14%), Y (12%), I1 replicon (10.5%) were the major plasmid families detected in the present study. Conclusion: Many isolates exhibited the presence of more than one Incompatibility (Inc.) group plasmids, conferring multidrug resistance to the isolates. The study highlights the need for further research to study the association between plasmid families and their respective antibiotic resistance profiles for a given geographical niche and the need to devise further methods to target these epidemic plasmids.

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Isolation, Identification, and Antimicrobial Susceptibility of Bacteria Associated with Waterpipe Contaminants in Selected Area of Saudi Arabia

BioMed Research International ◽

10.1155/2017/8042603 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 8

Author(s):

Mohammed Alaidarous ◽

Meshal Alanazi ◽

Ahmed Abdel-Hadi

Keyword(s):

Saudi Arabia ◽

Antimicrobial Susceptibility ◽

Multidrug Resistant ◽

Health Concern ◽

Contamination Rate ◽

Bacterial Isolates ◽

Biochemical Tests ◽

Susceptibility Data ◽

Public Health Professionals ◽

Vitek 2

This study highlights the level of microbial contamination of waterpipe components in selected area of Saudi Arabia and the resistance of selected bacteria to different antibiotics was determined. A series of biochemical tests, microscopic examination, and screening on Vitek 2 compact (bioMérieux Inc., USA) system were done to characterize the bacterial isolates. Out of 132 samples investigated, 7 mouthpiece samples and 48 water bowl samples showed positivity on culture. The percentage of contamination rate was higher in water bowl (69.69%) than in mouthpieces (10.6%) for all selected areas. A total of 55 bacterial isolates were identified which included Gram-negative (28) and Gram-positive (27) bacteria. Antimicrobial susceptibility data showed more resistance to bacteria isolated from water bowl than bacteria isolated from mouthpiece. In addition, one isolate which was confirmed as methicillin-resistant Staphylococcus aureus and Klebsiella pneumoniae was resistant to antibiotics which are commonly used to treat pneumonia. Water bowl of waterpipe instrument is significantly contaminated with different bacterial pathogens including multidrug-resistant and pneumonia causing bacteria, which are a real health concern among waterpipe smokers. The presented data could assist public health professionals to raise the concerns regarding cleaning practices of waterpipe components and highlights the risk posed among the waterpipe smokers.

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A Critical Evaluation of Newer β-Lactam Antibiotics for Treatment of Pseudomonas aeruginosa Infections

Annals of Pharmacotherapy ◽

10.1177/1060028020974003 ◽

2020 ◽

pp. 106002802097400

Author(s):

Kathleen C. Blomquist ◽

David E. Nix

Keyword(s):

Pseudomonas Aeruginosa ◽

Clinical Data ◽

Therapeutic Potential ◽

Data Extraction ◽

Relevant Literature ◽

Acquired Resistance ◽

Critical Evaluation ◽

Multidrug Resistant ◽

Resistance Mechanisms ◽

Study Selection

Objective: This article critically evaluates common Pseudomonas aeruginosa resistance mechanisms and the properties newer β-lactam antimicrobials possess to evade these mechanisms. Data Sources: An extensive PubMed, Google Scholar, and ClinicalTrials.gov search was conducted (January 1995 to July 2020) to identify relevant literature on epidemiology, resistance mechanisms, antipseudomonal agents, newer β-lactam agents, and clinical data available pertaining to P aeruginosa. Study Selection and Data Extraction: Relevant published articles and package inserts were reviewed for inclusion. Data Synthesis: Therapeutic options to treat P aeruginosa infections are limited because of its intrinsic and acquired resistance mechanisms. The goal was to identify advances with newer β-lactams and characterize improvements in therapeutic potential for P aeruginosa infections. Relevance to Patient Care and Clinical Practice: Multidrug-resistant (MDR) P aeruginosa isolates are increasingly encountered from a variety of infections. This review highlights potential activity gains of newer β-lactam antibacterial drugs and the current clinical data to support their use. Pharmacists will be asked to recommend or evaluate the use of these agents and need to be aware of information specific to P aeruginosa, which differs from experience derived from Enterobacterales infections. Conclusions: Newer agents, including ceftazidime-avibactam, ceftolozane-tazobactam, imipenem-relebactam, and cefiderocol, are useful for the treatment of MDR P aeruginosa infections. These agents offer improved efficacy and less toxicity compared with aminoglycosides and polymyxins and can be used for pathogens that are resistant to first-line antipseudomonal β-lactams. Selection of one agent over another should consider availability, turnaround of susceptibility testing, and product cost. Efficacy data specific for pseudomonal infections are limited, and there are no direct comparisons between the newer agents.

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A Novel Cecropin D-Derived Short Cationic Antimicrobial Peptide Exhibits Antibacterial Activity Against Wild-Type and Multidrug-Resistant Strains of Klebsiella pneumoniae and Pseudomonas aeruginosa

Evolutionary Bioinformatics ◽

10.1177/1176934320936266 ◽

2020 ◽

Vol 16 ◽

pp. 117693432093626

Author(s):

Iván Darío Ocampo-Ibáñez ◽

Yamil Liscano ◽

Sandra Patricia Rivera-Sánchez ◽

José Oñate-Garzón ◽

Ashley Dayan Lugo-Guevara ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Klebsiella Pneumoniae ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Health Concern ◽

Wild Type ◽

Cationic Antimicrobial Peptide ◽

Promising Alternative ◽

Resistant Strains

Infections caused by multidrug-resistant (MDR) Pseudomonas aeruginosa and Klebsiella pneumoniae are a serious worldwide public health concern due to the ineffectiveness of empirical antibiotic therapy. Therefore, research and the development of new antibiotic alternatives are urgently needed to control these bacteria. The use of cationic antimicrobial peptides (CAMPs) is a promising candidate alternative therapeutic strategy to antibiotics because they exhibit antibacterial activity against both antibiotic susceptible and MDR strains. In this study, we aimed to investigate the in vitro antibacterial effect of a short synthetic CAMP derived from the ΔM2 analog of Cec D-like (CAMP-CecD) against clinical isolates of K pneumoniae (n = 30) and P aeruginosa (n = 30), as well as its hemolytic activity. Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of CAMP-CecD against wild-type and MDR strains were determined by the broth microdilution test. In addition, an in silico molecular dynamic simulation was performed to predict the interaction between CAMP-CecD and membrane models of K pneumoniae and P aeruginosa. The results revealed a bactericidal effect of CAMP-CecD against both wild-type and resistant strains, but MDR P aeruginosa showed higher susceptibility to this peptide with MIC values between 32 and >256 μg/mL. CAMP-CecD showed higher stability in the P aeruginosa membrane model compared with the K pneumoniae model due to the greater number of noncovalent interactions with phospholipid 1-Palmitoyl-2-oleyl-sn-glycero-3-(phospho-rac-(1-glycerol)) (POPG). This may be related to the boosted effectiveness of the peptide against P aeruginosa clinical isolates. Given the antibacterial activity of CAMP-CecD against wild-type and MDR clinical isolates of P aeruginosa and K pneumoniae and its nonhemolytic effects on human erythrocytes, CAMP-CecD may be a promising alternative to conventional antibiotics.

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In Vitro Bactericidal Activity of Human β-Defensin 3 against Multidrug-Resistant Nosocomial Strains

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.50.2.806-809.2006 ◽

2006 ◽

Vol 50 (2) ◽

pp. 806-809 ◽

Cited By ~ 80

Author(s):

Giuseppantonio Maisetta ◽

Giovanna Batoni ◽

Semih Esin ◽

Walter Florio ◽

Daria Bottai ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antimicrobial Activity ◽

Bactericidal Activity ◽

Stenotrophomonas Maltophilia ◽

Bactericidal Effect ◽

Multidrug Resistant ◽

Bacterial Strains ◽

Gram Negative

ABSTRACT The antimicrobial activity of human β-defensin 3 (hBD-3) against multidrug-resistant clinical isolates of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Acinetobacter baumannii was evaluated. A fast bactericidal effect (within 20 min) against all bacterial strains tested was observed. The presence of 20% human serum abolished the bactericidal activity of hBD-3 against gram-negative strains and reduced the activity of the peptide against gram-positive strains.

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