Halogen-Furan-2(5H)-One Derivatives Decrease Biofilm Production in Pseudomonas aeruginosa.

Clinical evidence has shown that bacterial infections are more difficult to eradicate when form-ing a biofilm aggregate than when are produced by bacteria in planktonic form. Therefore, com-pounds that inhibit biofilm formation could be used against severe infections. It has been re-ported that bromo 2-(5H) furanones inhibited biofilm formation by their anti-quorum sensing properties. To determine if the 2-(5H) furanone moiety is essential to induce inhibition of biofilm formation, we evaluated ten halogen 2-(5H) furanones derivates previously synthesized. Besides evaluating the inhibition of biofilm formation, we assessed pyocyanin production, swarming motility, and transcription of essential QS genes: rsaL, rhlA, pqsA and phz1 genes. Our results showed that although three bromo-furan-2(5H)-one-type derivatives (A1-A3) and two bromo-4-(phenylamino)-furan-2(5H)-one-type compounds (B2 and B6) inhibited the biofilm formation in both P. aeruginosa PA14 (reference) and PA64 (drug-resistant) strains only the furanones A1-A3 were efficient to inhibit QSS.

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Identification, Typing, Antifungal Resistance Profile, and Biofilm Formation ofCandida albicansIsolates from Lebanese Hospital Patients

BioMed Research International ◽

10.1155/2014/931372 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 13

Author(s):

Ibrahim Bitar ◽

Roy A. Khalaf ◽

Houda Harastani ◽

Sima Tokajian

Keyword(s):

Biofilm Formation ◽

Fungal Pathogens ◽

Recurrent Infection ◽

Multidrug Resistant ◽

Antifungal Resistance ◽

Drug Resistant ◽

Treatment Regimens ◽

Evolutionary Relatedness ◽

Resistant Strains ◽

Drug Resistant Strains

As leading opportunistic fungal pathogens identification and subtyping ofCandidaspecies are crucial in recognizing outbreaks of infection, recognizing particularly virulent strains, and detecting the emergence of drug resistant strains. In this study our objective was to compare identification ofCandida albicansby the hospitals through the use of conventional versus identification based on the ITS (Internal Transcribed Spacer) and to assess biofilm forming capabilities, drug resistance patterns and correlate these with MLST typing. ITS typing revealed a 21.2% hospital misidentification rate. Multidrug resistance to three drugs out of four tested was detected within 25% of the isolates raising concerns about the followed treatment regimens. Drug resistant strains as well as biofilm formers were phylogenetically related, with some isolates with significant biofilm forming capabilities being correlated to those that were multidrug resistant. Such isolates were grouped closely together in a neighbor-joining tree generated by MLST typing indicating phylogenetic relatedness, microevolution, or recurrent infection. In conclusion, this pilot study gives much needed insight concerningC. albicansisolates circulating in Lebanese hospitals and is the first study of its kind correlating biofilm formation, antifungal resistance, and evolutionary relatedness.

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Synthesis and biological evaluation of new cephalosporin derivatives containing cyclic disulfide moieties

10.1101/2021.11.03.467114 ◽

2021 ◽

Author(s):

Inga S. Shchelik ◽

Karl Gademann

Keyword(s):

Biofilm Formation ◽

Bacterial Infections ◽

Biological Evaluation ◽

Steady Increase ◽

Planktonic Cells ◽

Gram Negative ◽

Successful Group ◽

Resistant Strains ◽

Drug Resistant Strains ◽

Synthesis And Biological Evaluation

Due to a steady increase of microbial resistance, there is a need to increase the effectiveness of antibiotic performance by involving additional mechanisms of their penetration or retention for their better action. Cephalosporins are a successful group of antibiotics to combat pathogenic microorganisms, including drug-resistant strains. In this study, we investigated the effect of newly synthesized cephalosporin derivatives with cyclic disulfide modifications against several Gram-positive and Gram-negative strains as well as against biofilm formation. The incorporation of asparagusic acid was found to be effective in improving the activity of the drug against Gram-negative strains. Furthermore, we could demonstrate the successful inhibition of biofilm formation for S. aureus and P. aeruginosa at similar concentrations as obtained against planktonic cells. We propose that the incorporation of cyclic disulfides is one additional strategy to improve antibiotic activity and to combat bacterial infections.

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Development of a penem antibiotic against Mycobacteroides abscessus

Communications Biology ◽

10.1038/s42003-020-01475-2 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Hunter R. Batchelder ◽

Elizabeth Story-Roller ◽

Evan P. Lloyd ◽

Amit Kaushik ◽

Kristina M. Bigelow ◽

...

Keyword(s):

Bacterial Infections ◽

Limit Of Detection ◽

Pharmacokinetic Profile ◽

Drug Resistant ◽

Resistant Strains ◽

Cure Rates ◽

Drug Resistant Strains ◽

Clinical Potential ◽

Penem Antibiotic ◽

Lactamase Inhibitor

Abstractβ-lactams are the most widely used antibiotic class to treat bacterial infections in humans. Mycobacteroides abscessus is an emerging pulmonary pathogen resistant to most antibiotics, including penicillins and cephalosporins. With no current FDA-approved treatment and cure rates <50%, there is a pressing need for effective therapies. Here we report T405, a new β-lactam of the penem subclass that exhibits potent activity against M. abscessus and a panel of drug-resistant strains isolated from cystic fibrosis patients. Additionally, in combination with the β-lactamase inhibitor avibactam, the rate of spontaneous resistance of M. abscessus to T405 approached the limit of detection. Lastly, we show the favorable pharmacokinetic profile of T405 in mice and the absence of toxicity at elevated dosage, which support the clinical potential of this compound.

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Gum arabic capped-silver nanoparticles inhibit biofilm formation by multi-drug resistant strains ofPseudomonas aeruginosa

Journal of Basic Microbiology ◽

10.1002/jobm.201300748 ◽

2014 ◽

Vol 54 (7) ◽

pp. 688-699 ◽

Cited By ~ 37

Author(s):

Mohammad Azam Ansari ◽

Haris Manzoor Khan ◽

Aijaz Ahmed Khan ◽

Swaranjit Singh Cameotra ◽

Quaiser Saquib ◽

...

Keyword(s):

Silver Nanoparticles ◽

Biofilm Formation ◽

Gum Arabic ◽

Drug Resistant ◽

Resistant Strains ◽

Drug Resistant Strains

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Antibacterial and Anti-Biofilm Activity of Omega-3 Polyunsaturated Fatty Acids against Periprosthetic Joint Infections-Isolated Multi-Drug Resistant Strains

Biomedicines ◽

10.3390/biomedicines9040334 ◽

2021 ◽

Vol 9 (4) ◽

pp. 334

Author(s):

Débora C. Coraça-Huber ◽

Stephan Steixner ◽

Alexander Wurm ◽

Michael Nogler

Keyword(s):

Fatty Acids ◽

Biofilm Formation ◽

Drug Resistant ◽

Gingival Fibroblasts ◽

Omega 3 ◽

Joint Infections ◽

Epa And Dha ◽

Resistant Strains ◽

Drug Resistant Strains

Background: Implantable medical devices, such as prosthetics, catheters, and several other devices, have revolutionized medicine, but they increase the infection risk. In previous decades, commercially available antibiotics lost their activity against coagulase-negative Staphylococci (CoNS) and several other microorganisms. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are the two major omega-3 polyunsaturated fatty acids (ω-3 PUFAs) with antimicrobial properties. Materials and Methods: In this study, we tested the EPA and the DHA for its antibacterial and anti-biofilm activity in vitro against Staphylococcus epidermidis, Staphylococcus aureus, and different CoNS as reference strains and isolated from patients undergoing orthopedic treatment for implant infections. The tests were carried out with the strains in planktonic and biofilm form. Cytotoxicity assay was carried out with EPA and DHA using human gingival fibroblasts HGF-1. Results: The highest concentration of EPA and DHA promoted the complete killing of S. epidermidis 1457 and S. aureus ATCC 25923 in planktonic form. The fatty acids showed low activity against P. aeruginosa. EPA and DHA completely killed or significantly reduced the count of planktonic bacteria of the patient isolated strains. When incubated with media enriched with EPA and DHA, the biofilm formation was significantly reduced on S. epidermidis 1457 and not present on S. aureus ATCC 25923. The reduction or complete killing were also observed with the clinical isolates. The pre-formed biofilms showed reduction of the cell counting after treatment with EPA and DHA. Conclusion: In this study, the ω-3 PUFAs EPA and DHA showed antimicrobial and anti-biofilm activity in vitro against S. aureus, S. epidermidis, and P. aeruginosa, as well as against multi-drug resistant S. aureus and CoNS strains isolated from patients undergoing periprosthetic joint infections (PJI) treatment. Higher concentrations of the fatty acids showed killing activity on planktonic cells and inhibitory activity of biofilm formation. Although both substances showed antimicrobial activity, EPA showed better results in comparison with DHA. In addition, when applied on human gingival fibroblasts in vitro, EPA and DHA showed a possible protective effect on cells cultured in medium enriched with ethanol. Further studies are required to confirm the antimicrobial activity of EPA and DHA against multi-drug resistant strains and pan-drug resistant strains.

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Broad Spectrum Antimicrobial Activity of Licochalcones A and E against MDR (Multidrug Resistant) Strains of Clinical Origin

Natural Product Communications ◽

10.1177/1934578x1701201123 ◽

2017 ◽

Vol 12 (11) ◽

pp. 1934578X1701201 ◽

Cited By ~ 1

Author(s):

Jung-Eun Kim ◽

Goo Yoon ◽

Jung-Hyun Shim ◽

Seung-Sik Cho

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Bacterial Infections ◽

Multidrug Resistant ◽

Drug Resistant ◽

Baseline Information ◽

Resistant Strains ◽

Glycyrrhiza Inflata ◽

Drug Resistant Strains ◽

Potential Use

The aim of this study was to evaluate the antibacterial activity of the licochalcones A (1) and E (2) against drug resistant strains of clinical origin. The results indicate that the licochalcones had a broad inhibitory activity against tested bacteria. Compared to vancomycin and teicoplanin, these compounds provided weaker activity against non-MDR Staphylococcus aureus and Enterococcus but broader activity against MRSA and VRE strains. The results provide promising baseline information for the potential use of 1 and 2 from Glycyrrhiza inflata in the treatment of drug resistant bacterial infections.

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Molecular Detection of epsA-Mediated and Extracellular Polysaccharide-Mediated Biofilm Formation Among Multidrug Resistant Strains of Acinetobacter baumannii

Bioscience Biotechnology Research Communications ◽

10.21786/bbrc/14.4.43 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1660-1665

Author(s):

Sarojini K

Keyword(s):

Acinetobacter Baumannii ◽

Biofilm Formation ◽

Efflux Pump ◽

Pcr Amplification ◽

Multidrug Resistant ◽

P Value ◽

Low Grade ◽

Drug Resistant ◽

Resistant Strains ◽

Drug Resistant Strains

The epsA associated biofilm formation attributes to potent virulence in the drug resistant strains of Acinetobacter baumannii. This study is aimed to molecularly characterize the epsA gene among the multidrug resistant clinical isolates of A. baumannii and to assess the frequency of the same in different drug resistant groups. To detect the biofilm formation among the selected MDR strains of A. baumannii, semi-quantitative adherent bioassay was performed using crystal violet staining method. Further PCR amplification was done to screen the presence of epsA gene with further sequencing of the amplicons. Pearson’s correlation analysis was done to check the correlation of the occurrence of epsA gene with drug resistant strains (p-value<0.05). 58.9%, 31.5% and 0.9% of the strains were recorded as high grade, low grade and negative biofilm formers under biofilm assay. The epsA gene was observed in 14 MDR strains (19.17%) of A. baumannii with an amplicon size of 451bp. Co-occurrence of epsA gene was 100% in β-lactam, cephem and folate resistant strains followed by 71.4% among aminoglycosides, 57.1% against carbapenems and 14.2% in fluoroquinolone and efflux pump mediated resistant strains. The findings of the study suggest the co-occurrence of epsA gene mediated biofilm formation among the multidrug resistant strains of A. baumannii. Further studies on the same helps in designing new vaccines and drugs for the prevention and treatment of A. baumannii infections.

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