scholarly journals Biomimetic Electronic Devices for Measuring Bacterial Membrane Disruption

2019 ◽  
Vol 31 (11) ◽  
pp. 1808234
Author(s):  
Charalampos Pitsalidis ◽  
Anna‐Maria Pappa ◽  
Mintu Porel ◽  
Christine M. Artim ◽  
Gregorio C. Faria ◽  
...  
Keyword(s):  
Electronic Devices ◽  
Membrane Disruption ◽  
Bacterial Membrane

scholarly journals Biomimetic Electronic Devices for Measuring Bacterial Membrane Disruption

2018 ◽  
Vol 30 (39) ◽  
pp. 1803130 ◽  
Author(s):  
Charalampos Pitsalidis ◽  
Anna-Maria Pappa ◽  
Mintu Porel ◽  
Christine M. Artim ◽  
Gregorio C. Faria ◽  
...  
Keyword(s):  
Electronic Devices ◽  
Membrane Disruption ◽  
Bacterial Membrane

scholarly journals Alarmone Ap4A is elevated by aminoglycoside antibiotics and enhances their bactericidal activity

2019 ◽  
Vol 116 (19) ◽  
pp. 9578-9585 ◽  
Author(s):  
Xia Ji ◽  
Jin Zou ◽  
Haibo Peng ◽  
Anne-Sophie Stolle ◽  
Ruiqiang Xie ◽  
...  
Keyword(s):  
Therapeutic Index ◽  
Fold Increase ◽  
Multidrug Resistant ◽  
Trna Synthetase ◽  
Aminoglycoside Antibiotics ◽  
Membrane Disruption ◽  
Bacterial Membrane ◽  
Bacterial Killing ◽  
Messenger Molecules ◽  
Increased Susceptibility

Second messenger molecules play important roles in the responses to various stimuli that can determine a cell's fate under stress conditions. Here, we report that lethal concentrations of aminoglycoside antibiotics result in the production of a dinucleotide alarmone metabolite–diadenosine tetraphosphate (Ap4A), which promotes bacterial cell killing by this class of antibiotics. We show that the treatment ofEscherichia coliwith lethal concentrations of kanamycin (Kan) dramatically increases the production of Ap4A. This elevation of Ap4A is dependent on the production of a hydroxyl radical and involves the induction of the Ap4A synthetase lysyl-tRNA synthetase (LysU). Ectopic alteration of intracellular Ap4A concentration via the elimination of the Ap4A phosphatase diadenosine tetraphosphatase (ApaH) and the overexpression of LysU causes over a 5,000-fold increase in bacterial killing by aminoglycosides. This increased susceptibility to aminoglycosides correlates with bacterial membrane disruption. Our findings provide a role for the alarmone Ap4A and suggest that blocking Ap4A degradation or increasing its synthesis might constitute an approach to enhance aminoglycoside killing potency by broadening their therapeutic index and thereby allowing lower nontoxic dosages of these antibiotics to be used in the treatment of multidrug-resistant infections.

Synthesis of antimicrobial cyclodextrins bearing polyarylamino and polyalkylamino groups via click chemistry for bacterial membrane disruption

2014 ◽  
Vol 50 (41) ◽  
pp. 5444 ◽  
Author(s):  
Hatsuo Yamamura ◽  
Yuuki Sugiyama ◽  
Kensuke Murata ◽  
Takanori Yokoi ◽  
Ryuji Kurata ◽  
...  
Keyword(s):  
Click Chemistry ◽  
Membrane Disruption ◽  
Bacterial Membrane

scholarly journals Construction of Antibacterial N ‐Halamine Polymer Nanomaterials Capable of Bacterial Membrane Disruption for Efficient Anti‐Infective Wound Therapy

2019 ◽  
Vol 19 (4) ◽  
pp. 1970010 ◽  
Author(s):  
Yangyang Gao ◽  
Nan Song ◽  
Wenxin Liu ◽  
Alideertu Dong ◽  
Yan‐Jie Wang ◽  
...  
Keyword(s):  
Membrane Disruption ◽  
Bacterial Membrane ◽  
Wound Therapy

Construction of Antibacterial N ‐Halamine Polymer Nanomaterials Capable of Bacterial Membrane Disruption for Efficient Anti‐Infective Wound Therapy

2019 ◽  
Vol 19 (4) ◽  
pp. 1800453 ◽  
Author(s):  
Yangyang Gao ◽  
Nan Song ◽  
Wenxin Liu ◽  
Alideertu Dong ◽  
Yan‐Jie Wang ◽  
...  
Keyword(s):  
Membrane Disruption ◽  
Bacterial Membrane ◽  
Wound Therapy

scholarly journals The inhibition of bacterial growth by hypochlorous acid. Possible role in the bactericidal activity of phagocytes

1988 ◽  
Vol 254 (3) ◽  
pp. 685-692 ◽  
Author(s):  
S M McKenna ◽  
K J A Davies
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Cell Division ◽  
Protein Degradation ◽  
Bacterial Growth ◽  
Colony Formation ◽  
Hypochlorous Acid ◽  
Selective Inhibition ◽  
Membrane Disruption ◽  
Bacterial Membrane

The ‘respiratory burst’ of phagocytes such as neutrophils generates superoxide which forms H2O2 by dismutation. H2O2 and Cl- ions serve as substrates for the enzyme myeloperoxidase to generate hypochlorous acid (HOCl). HOCl is thought to play an important role in bacterial killing, but its mechanism of action is not well characterized. Furthermore, although many studies in vitro have shown HOCl to be a damaging oxidant with little or no specificity (particularly at high concentrations), bacteria which have been ingested by phagocytes appear to experience a rapid and selective inhibition of cell division. Bacterial membrane disruption, protein degradation, and inhibition of protein synthesis, do not seem to occur in the early phases of phagocyte action. We have now found that low concentrations of HOCl exert a rapid and selective inhibition of bacterial growth and cell division, which can be blocked by taurine or amino acids. Only 20 microM-HOCl was required for 50% inhibition of bacterial growth (5 x 10(8) Escherichia coli/ml), and 50 microM-HOCl completely inhibited cell division (colony formation). These effects were apparent within 5 min of HOCl exposure, and were not reversed by extensive washings. DNA synthesis (incorporation of [3H]-thymidine) was significantly affected by even a 1 min exposure to 50 microM-HOCl, and decreased by as much as 96% after 5 min. In contrast, bacterial membrane disruption and extensive protein degradation/fragmentation (release of acid-soluble counts from [3H]leucine-labelled cells) were not observed at concentrations below 5 mM-HOCl. Protein synthesis (incorporation of [3H]leucine) was only inhibited by 10-30% following 5 min exposure to 50 microM-HOCl, although longer exposure produced more marked reductions (80% after 30 min). Neutrophils deficient in myeloperoxidase cannot convert H2O2 to HOCl, yet can kill bacteria. We have found that H2O2 is only 6% as effective as HOCl in inhibiting E. coli growth and cell division (0.34 mM-H2O2 required for 50% inhibition of colony formation), and taurine or amino acids do not block this effect. Our results are consistent with a rapid and selective inhibition of bacterial cell division by HOCl in phagocytes. H2O2 may substitute for HOCl in myeloperoxidase deficiency, but by a different mechanism and at a greater metabolic cost.

Quaternary Ammonium Substituted Pullulan Accelerates Wound Healing and Disinfects Staphylococcus aureus Infected Wounds in Mouse Through an Atypical ‘Non-Pore Forming’ Pathway of Bacterial Membrane Disruption

2021 ◽  
Author(s):  
Shounak Roy ◽  
Monika Kumari ◽  
Prakash Haloi ◽  
Saurabh Chawla ◽  
V. Badireenath Konkimalla ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Wound Healing ◽  
Quaternary Ammonium ◽  
Membrane Disruption ◽  
Bacterial Membrane ◽  
Drug Resistant ◽  
Resistance Development ◽  
Infected Wounds ◽  
Inducing Resistance

Emergence of multi-drug resistant pathogens has fueled the search for alternatives to the existing line of antibiotics that can eradicate pathogens without inducing resistance development. Here, we report the accelerated...

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