Activities of cholic acid-derived antimicrobial agents against multidrug-resistant bacteria

Currently, the emergence and ongoing dissemination of antimicrobial resistance among bacteria are critical health and economic issue, leading to increased rates of morbidity and mortality related to bacterial infections. Research and development for new antimicrobial agents is currently needed to overcome this problem. Among the different approaches studied, bacteriocins seem to be a promising possibility. These molecules are peptides naturally synthesized by ribosomes, produced by both Gram-positive bacteria (GPB) and Gram-negative bacteria (GNB), which will allow these bacteriocin producers to survive in highly competitive polymicrobial environment. Bacteriocins exhibit antimicrobial activity with variable spectrum depending on the peptide, which may target several bacteria. Already used in some areas such as agro-food, bacteriocins may be considered as interesting candidates for further development as antimicrobial agents used in health contexts, particularly considering the issue of antimicrobial resistance. The aim of this review is to present an updated global report on the biology of bacteriocins produced by GPB and GNB, as well as their antibacterial activity against relevant bacterial pathogens, and especially against multidrug-resistant bacteria.

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Antimicrobial O-Alkyl Derivatives of Naringenin and Their Oximes Against Multidrug-Resistant Bacteria

Molecules ◽

10.3390/molecules25163642 ◽

2020 ◽

Vol 25 (16) ◽

pp. 3642 ◽

Cited By ~ 1

Author(s):

Anna Duda-Madej ◽

Joanna Kozłowska ◽

Paweł Krzyżek ◽

Mirosław Anioł ◽

Alicja Seniuk ◽

...

Keyword(s):

Antimicrobial Agents ◽

Methicillin Resistant Staphylococcus Aureus ◽

Quantitative Measure ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Beta Lactam ◽

Multidrug Resistant Bacteria ◽

Alkyl Derivatives ◽

Vancomycin Resistant ◽

Derivatives Of

New antimicrobial agents are needed to address infections caused by multidrug-resistant bacteria. Here, we are reporting novel O-alkyl derivatives of naringenin and their oximes, including novel compounds with a naringenin core and O-hexyl chains, showing activity against clinical strains of clarithromycin-resistant Helicobacter pylori, vancomycin-resistant Enterococcus faecalis, methicillin-resistant Staphylococcus aureus, and beta-lactam-resistant Acinetobacter baumannii and Klebsiella pneumoniae. The minimum inhibitory concentrations (MICs), which provide a quantitative measure of antimicrobial activity, were in the low microgram range for the selected compounds. Checkerboard assays for the most active compounds in combination with antibiotics revealed interactions that varied from synergistic to neutral.

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Biodegradable Nanofibrous Membranes for Medical and Personal Protection Applications: Manufacturing, Anti-COVID-19 and Anti-Multidrug Resistant Bacteria Evaluation

Materials ◽

10.3390/ma14143862 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3862

Author(s):

Latifah Abdullah Alshabanah ◽

Mohamed Hagar ◽

Laila A. Al-Mutabagani ◽

Ghada M. Abozaid ◽

Salwa M. Abdallah ◽

...

Keyword(s):

Antimicrobial Agents ◽

Multidrug Resistant ◽

Standard Test ◽

Test Method ◽

Resistant Bacteria ◽

Drug Resistant ◽

Personal Protection ◽

Multidrug Resistant Bacteria ◽

Standard Test Method ◽

Nanofibrous Membranes

Biodegradable nanofibrous hybrid membranes of polyvinyl alcohol (PVA) with ZnO and CuO nanoparticles were manufactured and characterized, and their anti-COVID-19 and anti-multidrug resistant bacteria activities were also evaluated. The morphological structures of the prepared PVA composites nanofibers were observed by scanning electron microscope (SEM), which revealed a homogenous pattern of the developed nanofibers, with an average fibrous diameter of 200–250 nm. Moreover, the results of the SEM showed that the fiber size changed with the type and the concentration of the metal oxide. Moreover, the antiviral and antibacterial potential capabilities of the developed nanofibrous membranes were tested in blocking the viral fusion of SARS-COV-2, as a representative activity for COVID-19 deactivation, as well as for their activity against a variety of bacterial strains, including multi-drug resistant bacteria (MDR). The results revealed that ZnO loaded nanofibers were more potent antiviral agents than their CuO analogues. This antiviral action was attributed to the fact that inorganic metallic compounds have the ability to extract hydrogen bonds with viral proteins, causing viral rupture or morphological changes. On the other hand, the anti-multi-drug resistant activity of the prepared nanofibers was also evaluated using two techniques; the standard test method for determining the antimicrobial activity of immobilized antimicrobial agents under dynamic contact conditions and the standard test method for determining the activity of incorporated antimicrobial agents in polymeric or hydrophobic materials. Both techniques proved the superiority of the ZnO loaded nanofibers over the CuO loaded fibers. The results of the antiviral and antibacterial tests showed the effectiveness of such nanofibrous formulas, not only for medical applications, but also for the production of personal protection equipment, such as gowns and textiles.

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Efficacy of Tigecycline and Linezolid Against Pan-Drug-Resistant Bacteria Isolated From Companion Dogs in South Korea

Frontiers in Veterinary Science ◽

10.3389/fvets.2021.693506 ◽

2021 ◽

Vol 8 ◽

Author(s):

Dong-Hyun Kim ◽

Jung-Hyun Kim

Keyword(s):

South Korea ◽

Antimicrobial Agents ◽

Companion Animals ◽

Multidrug Resistant ◽

Diffusion Method ◽

Clinical Samples ◽

Resistant Bacteria ◽

Drug Resistant ◽

Multidrug Resistant Bacteria ◽

Companion Dogs

The emergence of multidrug-resistant bacteria in companion animals is an increasing concern in view of the concept of One Health. The antimicrobials linezolid (LZD) and tigecycline (TGC) are effective against multidrug-resistant bacteria isolated from humans; however, thus far, no previous study has evaluated the efficacy of these drugs against bacteria isolated from companion animals. This study aimed to evaluate the efficacy of LZD and TGC against bacteria that were isolated from companion dogs and showed resistance to all classes of antimicrobial agents. Clinical samples (auditory channel, eye, skin, and urine) were collected from dogs that visited the Veterinary Medical Teaching Hospital of Konkuk University (Seoul, South Korea) from October 2017 to September 2020. In total, 392 bacterial isolates were obtained, of which 85 were resistant to all classes of antimicrobial agents tested and were, therefore, considered potentially pan-drug resistant (PDR). The susceptibility of isolates to LZD and TGC was determined by the disk diffusion method and interpreted using the Clinical Laboratory Standards Institute guidelines. In total, 95.6% (43/45) and 97.8% (44/45) of gram-positive isolates were susceptible to LZD and TGC, respectively, whereas 82.5% (33/40) of gram-negative isolates were sensitive to TGC. In conclusion, both agents showed favorable efficacy, with the susceptibility rates for all potential PDR bacteria, except Pseudomonas spp., ranging from 72.7 to 100%. Thus, these drugs may serve as excellent antimicrobial options for veterinary medicine in the future.

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Genetically Engineered Phages: a Review of Advances over the Last Decade

Microbiology and Molecular Biology Reviews ◽

10.1128/mmbr.00069-15 ◽

2016 ◽

Vol 80 (3) ◽

pp. 523-543 ◽

Cited By ~ 158

Author(s):

Diana P. Pires ◽

Sara Cleto ◽

Sanna Sillankorva ◽

Joana Azeredo ◽

Timothy K. Lu

Keyword(s):

Antimicrobial Agents ◽

Phage Therapy ◽

Multidrug Resistant ◽

Genetically Engineered ◽

Resistant Bacteria ◽

Early 20Th Century ◽

New Materials ◽

Multidrug Resistant Bacteria ◽

Challenges And Opportunities ◽

Future Work

SUMMARYSoon after their discovery in the early 20th century, bacteriophages were recognized to have great potential as antimicrobial agents, a potential that has yet to be fully realized. The nascent field of phage therapy was adversely affected by inadequately controlled trials and the discovery of antibiotics. Although the study of phages as anti-infective agents slowed, phages played an important role in the development of molecular biology. In recent years, the increase in multidrug-resistant bacteria has renewed interest in the use of phages as antimicrobial agents. With the wide array of possibilities offered by genetic engineering, these bacterial viruses are being modified to precisely control and detect bacteria and to serve as new sources of antibacterials. In applications that go beyond their antimicrobial activity, phages are also being developed as vehicles for drug delivery and vaccines, as well as for the assembly of new materials. This review highlights advances in techniques used to engineer phages for all of these purposes and discusses existing challenges and opportunities for future work.

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Activity of topical antimicrobial agents against multidrug-resistant bacteria recovered from burn patients

Burns ◽

10.1016/j.burns.2010.05.013 ◽

2010 ◽

Vol 36 (8) ◽

pp. 1172-1184 ◽

Cited By ~ 48

Author(s):

Jessie S. Glasser ◽

Charles H. Guymon ◽

Katrin Mende ◽

Steven E. Wolf ◽

Duane R. Hospenthal ◽

...

Keyword(s):

Antimicrobial Agents ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Burn Patients ◽

Multidrug Resistant Bacteria ◽

Topical Antimicrobial

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Antibacterial activity of total flavonoids from Ilex rotunda Thunb. and different antibacterials on different multidrug-resistant bacteria alone or in combination

10.1101/457911 ◽

2018 ◽

Author(s):

Yongji Wu ◽

Beibei Chai ◽

Lizhen Wang ◽

Weijia Jiang ◽

Mei Hu ◽

...

Keyword(s):

Antibacterial Activity ◽

Bacterial Resistance ◽

Antimicrobial Agents ◽

Combined Therapy ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Total Flavonoids ◽

Multidrug Resistant Bacteria ◽

Minimal Inhibitory Concentrations ◽

Ilex Rotunda

AbstractThe problem of bacterial resistance is becoming more and more serious, which has become an urgent problem to be solved in human and veterinary. One approach to control and delay bacterial resistance is combination therapy in which antibiotics are given together with other antimicrobial or non-antimicrobial agents. Studies have shown that flavonoids from Traditional Chinese medicine (TCM) possess a high level of antibacterial activity against antibiotic resistant strains. The aim of this study was to evaluate the antibacterial effects of a combined therapy of total flavonoids from Ilex rotunda Thunb. and antibiotics against seven kinds of veterinary bacteria which were multidrug resistance bacteria. A microdilution checkerboard method was used to determine the minimal inhibitory concentrations of both types of antimicrobials, alone and in combination. The fractional inhibitory concentration index was calculated and used to classify observed collective antibacterial activity as synergistic, additive, indifferent or antagonistic.From the performed tests, the total flavonoids and antimicrobial agents were combined to inhibit different multidrug-resistant bacteria, such as Escherichia coli, Streptococcus, Pseudomonas aeruginosa, Enterococcus faecalis, Proteus vulgaris, Staphylococcus aureus, Acinetobacter baumannii. For these bacteria, total flavonoids from Ilex Rotunda Thunb. presented synergistic or additive with different antibiotics and had a certain antibacterial effect on the separated multidrug-resistant bacteria. The study shows total flavonoids from Ilex rotunda Thunb. have potential as adjuvants for the treatment of animal bacterial diseases.

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