Correction to: Europium and terbium Schiff base peptide complexes as potential antimicrobial agents against Salmonella typhimurium and Pseudomonas aeruginosa

Introduction: The biofilm formation by Pseudomonas aeruginosa seems to protect the bacteria from antibiotics since these entities are highly resistant to such antimicrobial agents. The aim of this study was to investigate the role of Lactobacillus salivarus, Lactobacillus plantarum supernatants and CuII Schiff base complex in eliminating planktonic cells and biofilm of P. aeruginosa. Methods: : One hundred specimens of blood, urine, cerebrospinal fluid, respiratory samples, and wound swabs were collected from patients attending three hospitals in Mashhad. All specimens were identified by biochemical tests. The susceptibility of the isolates to the conventional antibiotics were assessed using disk diffusion method. The biofilm formation ability of P. aeruginosa isolates was evaluated by crystal violet assay and confirmed using PCR. The anti-planktonic and anti-biofilm ability of L. salivarus, L. plantarum supernatants and CuII Schiff base complex was evaluated separately in P. aeruginosa isolates. Results and Conclusion: The highest and lowest resistance rates was detected in Cefazoline (95%) and cefepime (23%), respectively. The thickest biofilm was produced by 8% of P. aeruginosa isolates, 9% and 83% of the isolates were considered as moderate and weak biofilm producers, respectively. The rhlR and lasR genes was reported in 100% of the isolates, but algD gene was existence in 92% of them. Particularly, the CuII Schiff base complex could affect both planktonic and biofilm cells by the lowest concentration in comparison of probiotic supernatants. L. plantarum supernatant inhibited planktonic cells at a lower concentration than L. salivarius. Also, L. salivarius showed better antibiofilm activity than another probiotic in lower doses of supernatant. Unlike that these compounds have not completely eliminated biofilm cells, but only reduced the biofilm formation.Metal Schiff base complex and Lactobacillus supernatants is a potent antimicrobial agent against Pseudomonas aeruginosa biofilm cells.

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Evaluation the Antimicrobial Activity of Artemisia and Portulaca Plant Extracts in Beef Burger

Food Science and Nutrition Studies ◽

10.22158/fsns.v1n1p31 ◽

2017 ◽

Vol 1 (1) ◽

pp. 31 ◽

Cited By ~ 1

Author(s):

Marwa Al-Moghazy ◽

M. S. Ammar ◽

Mohamed M. Sief ◽

Sherif R. Mohamed

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Salmonella Typhimurium ◽

Antimicrobial Agents ◽

Biological Activities ◽

Control Sample ◽

Meat Products ◽

Consumer Health ◽

Negative Effects ◽

Beef Burger

Medicinal plants contain substances can alternate the traditional chemical preservatives which used for preserving meat products that have negative effects on consumer health. Several biological activities have been reported for Artemisia and Portulaca as antimicrobial agents, so the current study focused on using Artemisia and Portulaca extracts as antimicrobial agents in beef burger. Phytochemical of Artemisia and Portulaca extracts were analyzed, and both extracts contain alkaloids, flavonoids, phenols, trepenoids and saponin. The results show that Artemisia extract was inhibited all tested microorganisms (Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhimurium, Listeria monocytogenes and E.coli O157:H7) while, Portulaca extract affect Staphylococcus aureus only. The Minimum Cidal Concentration (MCC) and Minimum Inhibitory Concentration (MIC) were carried out for testing microorganisms, since Artemisia extract was very effective against Staphylococcus aureus followed by E.coli, Pseudomonas aeruginosa, Salmonella Typhimurium and L. monocytogenes. Artemisia and Portulaca extracts were separately applied in beef burger as antimicrobials at levels 1% and 1.5%. The sensory evaluation of treated beef burger showed no significant differences between control sample and treatments containing Portulaca extract while, the addition of Artmesia extract had a detrimental effect on taste of beef burger since it causes formation of bitter taste.

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Pseudomonas aeruginosa PA14 Enhances the Efficacy of Norfloxacin against Staphylococcus aureus Newman Biofilms

Journal of Bacteriology ◽

10.1128/jb.00159-20 ◽

2020 ◽

Vol 202 (18) ◽

Cited By ~ 1

Author(s):

Giulia Orazi ◽

Fabrice Jean-Pierre ◽

George A. O’Toole

Keyword(s):

Cystic Fibrosis ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antimicrobial Agents ◽

Respiratory Infections ◽

Multiple Infection ◽

Bacterial Biofilms ◽

Interspecies Interactions ◽

Chronic Infections ◽

Content Type

ABSTRACT The thick mucus within the airways of individuals with cystic fibrosis (CF) promotes frequent respiratory infections that are often polymicrobial. Pseudomonas aeruginosa and Staphylococcus aureus are two of the most prevalent pathogens that cause CF pulmonary infections, and both are among the most common etiologic agents of chronic wound infections. Furthermore, the ability of P. aeruginosa and S. aureus to form biofilms promotes the establishment of chronic infections that are often difficult to eradicate using antimicrobial agents. In this study, we found that multiple LasR-regulated exoproducts of P. aeruginosa, including 2-heptyl-4-hydroxyquinoline N-oxide (HQNO), siderophores, phenazines, and rhamnolipids, likely contribute to the ability of P. aeruginosa PA14 to shift S. aureus Newman norfloxacin susceptibility profiles. Here, we observe that exposure to P. aeruginosa exoproducts leads to an increase in intracellular norfloxacin accumulation by S. aureus. We previously showed that P. aeruginosa supernatant dissipates the S. aureus membrane potential, and furthermore, depletion of the S. aureus proton motive force recapitulates the effect of the P. aeruginosa PA14 supernatant on shifting norfloxacin sensitivity profiles of biofilm-grown S. aureus Newman. From these results, we hypothesize that exposure to P. aeruginosa PA14 exoproducts leads to increased uptake of the drug and/or an impaired ability of S. aureus Newman to efflux norfloxacin. Surprisingly, the effect observed here of P. aeruginosa PA14 exoproducts on S. aureus Newman susceptibility to norfloxacin seemed to be specific to these strains and this antibiotic. Our results illustrate that microbially derived products can alter the ability of antimicrobial agents to kill bacterial biofilms. IMPORTANCE Pseudomonas aeruginosa and Staphylococcus aureus are frequently coisolated from multiple infection sites, including the lungs of individuals with cystic fibrosis (CF) and nonhealing diabetic foot ulcers. Coinfection with P. aeruginosa and S. aureus has been shown to produce worse outcomes compared to infection with either organism alone. Furthermore, the ability of these pathogens to form biofilms enables them to cause persistent infection and withstand antimicrobial therapy. In this study, we found that P. aeruginosa-secreted products dramatically increase the ability of the antibiotic norfloxacin to kill S. aureus biofilms. Understanding how interspecies interactions alter the antibiotic susceptibility of bacterial biofilms may inform treatment decisions and inspire the development of new therapeutic strategies.

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Advances in Understanding of the Copper Homeostasis in Pseudomonas aeruginosa

International Journal of Molecular Sciences ◽

10.3390/ijms22042050 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2050

Author(s):

Lukas Hofmann ◽

Melanie Hirsch ◽

Sharon Ruthstein

Keyword(s):

Pseudomonas Aeruginosa ◽

Pathogenic Bacteria ◽

Antimicrobial Agents ◽

Efflux Pump ◽

Copper Homeostasis ◽

The United States ◽

World Health ◽

Cross Resistance ◽

Metabolism Regulation ◽

Target Sites

Thirty-five thousand people die as a result of more than 2.8 million antibiotic-resistant infections in the United States of America per year. Pseudomonas aeruginosa (P. aeruginosa) is classified a serious threat, the second-highest threat category of the U.S. Department of Health and Human Services. Among others, the World Health Organization (WHO) encourages the discovery and development of novel antibiotic classes with new targets and mechanisms of action without cross-resistance to existing classes. To find potential new target sites in pathogenic bacteria, such as P. aeruginosa, it is inevitable to fully understand the molecular mechanism of homeostasis, metabolism, regulation, growth, and resistances thereof. P. aeruginosa maintains a sophisticated copper defense cascade comprising three stages, resembling those of public safety organizations. These stages include copper scavenging, first responder, and second responder. Similar mechanisms are found in numerous pathogens. Here we compare the copper-dependent transcription regulators cueR and copRS of Escherichia coli (E. coli) and P. aeruginosa. Further, phylogenetic analysis and structural modelling of mexPQ-opmE reveal that this efflux pump is unlikely to be involved in the copper export of P. aeruginosa. Altogether, we present current understandings of the copper homeostasis in P. aeruginosa and potential new target sites for antimicrobial agents or a combinatorial drug regimen in the fight against multidrug resistant pathogens.

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Synthesis and Evaluation of Schiff Bases of 4-Amino-5-(chlorine substituted phenyl)-4H-1,2,4-triazole-3-thione as Antimicrobial Agents

Journal of Nepal Chemical Society ◽

10.3126/jncs.v41i1.30373 ◽

2020 ◽

Vol 41 (1) ◽

pp. 26-35

Author(s):

Kishor Devkota ◽

Govinda Pathak ◽

Bhushan Shakya

Keyword(s):

Schiff Base ◽

Schiff Bases ◽

Antimicrobial Agents ◽

Triazole Ring ◽

Antimicrobial Activities ◽

Biologically Active ◽

Spectral Techniques ◽

Schiff Base Derivatives ◽

Bacteria And Fungi ◽

Different Strains

Triazole ring system has attracted a continuously growing interest of synthetic organic chemists and those dealing with the medicinal compounds due to its versatile potential to interact with biological systems. Schiff bases are also considered as one of the most biologically active compounds. The aim of the present study was to synthesize new Schiff bases bearing triazole nucleus and to assess their antimicrobial activities. Four new Schiff base derivatives of 1,2,4-triazole-3-thione were synthesized by combining two different pharmacophores viz. triazole nucleus and Schiff base moiety and were characterized by spectral techniques (UV, FT-IR, and NMR). The Schiff bases were evaluated for antibacterial (Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae) and antifungal (Candida albicans) activities. The synthesized compounds exhibited good to moderate activities against different strains of bacteria and fungi tested.

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Effect of rat polymorphonuclear leukocyte granule components on the growth and survival of Pseudomonas aeruginosa and Salmonella typhimurium

Canadian Journal of Microbiology ◽

10.1139/m83-208 ◽

1983 ◽

Vol 29 (10) ◽

pp. 1339-1343 ◽

Cited By ~ 2

Author(s):

M. C. Modrzakowski ◽

D. Dosch-Meier ◽

R. L. Hodinka

Keyword(s):

Pseudomonas Aeruginosa ◽

Antimicrobial Activity ◽

Salmonella Typhimurium ◽

Polymorphonuclear Neutrophils ◽

Growth Enhancement ◽

Growth And Survival ◽

Whole Cells ◽

Phosphate Buffered Saline ◽

Antimicrobial Assay ◽

Enhancement Property

Granule contents from rat polymorphonuclear neutrophils were prepared by extraction with 0.2 M acetate buffer (pH 4.0), dialyzed against phosphate-buffered saline (pH 7.0), and tested for bactericidal activity against selected target bacteria. Salmonella typhimurium LT-2 and a series of progressively rough lipopolysaccharide outer membrane mutants derived from it were used to monitor antimicrobial activity. Although an antimicrobial potential was present in rat granule contents for S. typhimurium, the growth of Pseudomonas aeruginosa PAO-1 in antimicrobial assay mixtures containing rat granule contents was substantially enhanced over control values. The growth enhancement property of the granule protein was heat resistant and promoted increased oxygen consumption by whole cells.

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