Search results for "Anti-virulence"
showing 9 items of 9 documents
Synthesis and biofilm formation reduction of pyrazole-4-carboxamide derivatives in some Staphylococcus aureus strains
2016
The ability of several N-phenyl-1H-pyrazole-4-carboxamide derivatives and other pyrazoles opportunely modified at the positions 3, 4 and 5, to reduce the formation of the biofilm in some Staphylococcus aureus strains (ATCC 29213, ATCC 25923 and ATCC 6538) were investigated. All the tested compounds were able, although to a different extent, to reduce the biofilm formation of the three bacterial strains considered. Among these, the 1-(2,5-dichlorophenyl)-5-methyl-N-phenyl-1H-pyrazole-4-carboxamide 14 resulted as the best inhibitor of biofilm formation showing an IC50 ranging from 2.3 to 32 μM, against all the three strains of S. aureus. Compound 14 also shows a good protective effect in vivo…
New Thiazole Nortopsentin Analogues Inhibit Bacterial Biofilm Formation.
2018
New thiazole nortopsentin analogues were conveniently synthesized and evaluated for their activity as inhibitors of biofilm formation of relevant Gram-positive and Gram-negative pathogens. All compounds were able to interfere with the first step of biofilm formation in a dose-dependent manner, showing a selectivity against the staphylococcal strains. The most active derivatives elicited IC50 values against Staphylococcus aureus ATCC 25923, ranging from 0.40&ndash
Synthetic small molecules as anti-biofilm agents in the struggle against antibiotic resistance
2018
Abstract Biofilm formation significantly contributes to microbial survival in hostile environments and it is currently considered a key virulence factor for pathogens responsible for serious chronic infections. In the last decade many efforts have been made to identify new agents able to modulate bacterial biofilm life cycle, and many compounds have shown interesting activities in inhibiting biofilm formation or in dispersing pre-formed biofilms. However, only a few of these compounds were tested using in vivo models for their clinical significance. Contrary to conventional antibiotics, most of the anti-biofilm compounds act as anti-virulence agents as they do not affect bacterial growth. I…
1,2,4-Oxadiazole topsentin analogs as staphylococcal biofilm inhibitors targeting the bacterial transpeptidase sortase A
2020
The inhibition or prevention of biofilm formation represents an emerging strategy in the war against antibiotic resistance, interfering with key players in bacterial virulence. This approach includes the inhibition of the catalytic activity of transpeptidase sortase A (Srt A), a membrane enzyme responsible for covalently attaching a wide variety of adhesive matrix molecules to the peptidoglycan cell wall in Gram-positive strains. A new series of seventeen 1,2,4-oxadiazole derivatives was efficiently synthesized and screened as potential new anti-virulence agents. The ability of inhibiting biofilm formation was evaluated against both Gram-positive and Gram-negative pathogens. Remarkably, all…
2,6-Disubstituted imidazo[2,1-b][1,3,4]thiadiazole derivatives as potent staphylococcal biofilm inhibitors.
2019
Abstract A class of 36 new 2-(6-phenylimidazo[2,-1-b][1,3,4]thiadiazol-2-yl)-1H-indoles was efficiently synthesized and evaluated for their anti-biofilm properties against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 25923, S. aureus ATCC 6538 and Staphylococcus epidermidis ATCC 12228, and the Gram-negative strains Pseudomonas aeruginosa ATCC 15442 and Escherichia coli ATCC 25922. Many of these new compounds, were able to inhibit biofilm formation of the tested staphylococcal strains showing BIC50 lower than 10 μg/ml. In particular, derivatives 9c and 9h showed remarkable anti-biofilm activity against S. aureus ATCC 25923 with BIC50 values of 0.5 and 0.8 μg/ml, r…
Recent Developments in the Inhibition of Bacterial Adhesion as Promising Anti-Virulence Strategy
2023
Infectious diseases caused by antimicrobial-resistant strains have become a serious threat to global health, with a high social and economic impact. Multi-resistant bacteria exhibit various mechanisms at both the cellular and microbial community levels. Among the different strategies proposed to fight antibiotic resistance, we reckon that the inhibition of bacterial adhesion to host surfaces represents one of the most valid approaches, since it hampers bacterial virulence without affecting cell viability. Many different structures and biomolecules involved in the adhesion of Gram-positive and Gram-negative pathogens can be considered valuable targets for the development of promising tools t…
Curcumin derivatives as inhibitors of Gram positive and Gram negative biofilm formation
2015
New Anti-Adhesion Agents In The Development of Antivirulence Drugs
2015
Gram-positive bacteria are a significant cause of nosocomial and community-acquired infections associated with diseases of high morbidity and mortality. Moreover, antibiotic resistance of important Gram-positive pathogens, such as Staphylococcus aureus, Streptococcus pneumoniae and Enterococcus faecalis is one of the major worldwide health problems. Over the last decade, many studies have focused on agents that target the virulence of important pathogens without killing or inhibiting their growth therefore imposing limited selective pressure to promote the development and spread of resistance mechanisms [1]enterococci and streptococci, sortase A plays a critical role in Gram-positive bacter…