scholarly journals Uptake of Ozenoxacin and Other Quinolones in Gram-Positive Bacteria

2021 ◽  
Vol 22 (24) ◽  
pp. 13363
Author(s):  
Yuly López ◽  
Laura Muñoz ◽  
Domingo Gargallo-Viola ◽  
Rafael Cantón ◽  
Jordi Vila ◽  
...  
Keyword(s):  
Bacterial Cell ◽  
Dry Weight ◽  
Bacterial Cells ◽  
Topoisomerase Iv ◽  
Gram Positive Bacteria ◽  
Agar Disc ◽  
Key Factor ◽  
Ic50 Values ◽  
Important Challenge

The big problem of antimicrobial resistance is that it requires great efforts in the design of improved drugs which can quickly reach their target of action. Studies of antibiotic uptake and interaction with their target it is a key factor in this important challenge. We investigated the accumulation of ozenoxacin (OZN), moxifloxacin (MOX), levofloxacin (LVX), and ciprofloxacin (CIP) into the bacterial cells of 5 species, including Staphylococcus aureus (SA4-149), Staphylococcus epidermidis (SEP7602), Streptococcus pyogenes (SPY165), Streptococcus agalactiae (SAG146), and Enterococcus faecium (EF897) previously characterized.The concentration of quinolone uptake was estimated by agar disc-diffusion bioassay. Furthermore, we determined the inhibitory concentrations 50 (IC50) of OZN, MOX, LVX, and CIP against type II topoisomerases from S. aureus.The accumulation of OZN inside the bacterial cell was superior in comparison to MOX, LVX, and CIP in all tested species. The accumulation of OZN inside the bacterial cell was superior in comparison to MOX, LVX, and CIP in all tested species. The rapid penetration of OZN into the cell was reflected during the first minute of exposure with antibiotic values between 190 and 447 ng/mg (dry weight) of bacteria in all strains. Moreover, OZN showed the greatest inhibitory activity among the quinolones tested for both DNA gyrase and topoisomerase IV isolated from S. aureus with IC50 values of 10 and 0.5 mg/L, respectively. OZN intracellular concentration was significantly higher than that of MOX, LVX and CIP. All of these features may explain the higher in vitro activity of OZN compared to the other tested quinolones.

scholarly journals Synthesis, Antimicrobial Activity and Molecular Docking of Novel Thiourea Derivatives Tagged with Thiadiazole, Imidazole and Triazine Moieties as Potential DNA Gyrase and Topoisomerase IV Inhibitors

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2766 ◽  
Author(s):  
Heba E. Hashem ◽  
Abd El-Galil E. Amr ◽  
Eman S. Nossier ◽  
Elsayed A. Elsayed ◽  
Eman M. Azmy
Keyword(s):  
Antimicrobial Activity ◽  
Molecular Docking ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Topoisomerase Iv ◽  
Thiourea Derivatives ◽  
E Coli ◽  
Cytotoxicity Studies ◽  
Ic50 Values

To develop new antimicrobial agents, a series of novel thiourea derivatives incorporated with different moieties 2–13 was designed and synthesized and their biological activities were evaluated. Compounds 7a, 7b and 8 exhibited excellent antimicrobial activity against all Gram-positive and Gram-negative bacteria, and the fungal Aspergillus flavus with minimum inhibitory concentration (MIC) values ranged from 0.95 ± 0.22 to 3.25 ± 1.00 μg/mL. Furthermore, cytotoxicity studies against MCF-7 cells revealed that compounds 7a and 7b were the most potent with IC50 values of 10.17 ± 0.65 and 11.59 ± 0.59 μM, respectively. On the other hand, the tested compounds were less toxic against normal kidney epithelial cell lines (Vero cells). The in vitro enzyme inhibition assay of 8 displayed excellent inhibitory activity against Escherichia coli DNA B gyrase and moderate one against E. coli Topoisomerase IV (IC50 = 0.33 ± 1.25 and 19.72 ± 1.00 µM, respectively) in comparison with novobiocin (IC50 values 0.28 ± 1.45 and 10.65 ± 1.02 µM, respectively). Finally, the molecular docking was done to position compound 8 into the E. coli DNA B and Topoisomerase IV active pockets to explore the probable binding conformation. In summary, compound 8 may serve as a potential dual E. coli DNA B and Topoisomerase IV inhibitor.

scholarly journals Mixed Culture of Bacterial Cell for Large Scale DNA Storage

2020 ◽  
Author(s):  
Min Hao ◽  
Hongyan Qiao ◽  
Yanmin Gao ◽  
Zhaoguan Wang ◽  
Xin Qiao ◽  
...  
Keyword(s):  
Mixed Culture ◽  
Data Storage ◽  
Bacterial Cell ◽  
Living Cell ◽  
Large Scale ◽  
Digital Data ◽  
Human Society ◽  
Bacterial Cells ◽  
Digital Information

AbstractDNA emerged as novel material for mass data storage, the serious problem human society is facing. Taking advantage of current synthesis capacity, massive oligo pool demonstrated its high-potential in data storage in test tube. Herein, mixed culture of bacterial cells carrying mass oligo pool that was assembled in a high copy plasmid was presented as a stable material for large scale data storage. Living cells data storage was fabricated by a multiple-steps process, assembly, transformation and mixed culture. The underlying principle was explored by deep bioinformatic analysis. Although homology assembly showed sequence context dependent bias but the massive digital information oligos in mixed culture were constant over multiple successive passaging. In pushing the limitation, over ten thousand distinct oligos, totally 2304 Kbps encoding 445 KB digital data including texts and images, were stored in bacterial cell, the largest archival data storage in living cell reported so far. The mixed culture of living cell data storage opens up a new approach to simply bridge the in vitro and in vivo storage system with combined advantage of both storage capability and economical information propagation.

scholarly journals Design, Synthesis, and Antibacterial Screening of Some Novel Heteroaryl-Based Ciprofloxacin Derivatives as DNA Gyrase and Topoisomerase IV Inhibitors

2021 ◽  
Vol 14 (5) ◽  
pp. 399
Author(s):  
Lamya H. Al-Wahaibi ◽  
Amer A. Amer ◽  
Adel A. Marzouk ◽  
Hesham A.M. Gomaa ◽  
Bahaa G. M. Youssif ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Dna Gyrase ◽  
Bacterial Strains ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Antibacterial Screening ◽  
Ic50 Values

A novel series of ciprofloxacin hybrids comprising various heterocycle derivatives has been synthesized and structurally elucidated using 1H NMR, 13C NMR, and elementary analyses. Using ciprofloxacin as a reference, compounds 1–21 were screened in vitro against Gram-positive bacterial strains such as Staphylococcus aureus and Bacillus subtilis and Gram-negative strains such as Escherichia coli and Pseudomonas aeruginosa. As a result, many of the compounds examined had antibacterial activity equivalent to ciprofloxacin against test bacteria. Compounds 2–6, oxadiazole derivatives, were found to have antibacterial activity that was 88 to 120% that of ciprofloxacin against Gram-positive and Gram-negative bacteria. The findings showed that none of the compounds tested had antifungal activity against Aspergillus flavus, but did have poor activity against Candida albicans, ranging from 23% to 33% of fluconazole, with compound 3 being the most active (33% of fluconazole). The most potent compounds, 3, 4, 5, and 6, displayed an IC50 of 86, 42, 92, and 180 nM against E. coli DNA gyrase, respectively (novobiocin, IC50 = 170 nM). Compounds 4, 5, and 6 showed IC50 values (1.47, 6.80, and 8.92 µM, respectively) against E. coli topo IV in comparison to novobiocin (IC50 = 11 µM).

scholarly journals In Vitro Anti-Microbial Activity of Essential Oils and other Extracts from Salvia officinalis against Some Bacteria

2019 ◽  
Author(s):  
Amna Yousif Mohamed ◽  
Ahmed Ali Mustafa
Keyword(s):  
Antibacterial Activity ◽  
Essential Oils ◽  
Salvia Officinalis ◽  
Diffusion Test ◽  
Hexane Extraction ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Agar Disc

This study aimed to screen the antibacterial activity of essential oils from different parts (leave and stem) of Salvia officinalis against some Gram positive and Gram negative bacteria using agar disc diffusion test, then the extracts were prepared by hydro distillation to extract the essential oils. Maceration and hexane extraction by Soxhlet were used to obtain crude extracts from the leave and stem. Essential oils from the leaves and the ethyl acetate extract of the leaves showed higher antimicrobial activity, while hexane extract of leaves and stems showed moderate antibacterial activity. In contrast the essential oil from the stems showed very low antibacterial activity. It was observed that the results gram positive bacteria (staphylococcus aureus) was more sensitive than Gram negative (Echerichia coli).

scholarly journals Antibacterial efficacy of Jackfruit rag extract against clinically important pathogens and validation of its antimicrobial activity in Shigella dysenteriae infected Drosophila melanogaster infection model

2020 ◽  
Author(s):  
NV Dhwani ◽  
Gayathri Raju ◽  
Sumi E Mathew ◽  
Gaurav Baranwal ◽  
Shivakumar B Shivaram ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
Antibacterial Property ◽  
Mouse Fibroblast ◽  
Bacterial Cell Wall ◽  
Shigella Dysenteriae ◽  
Infection Model ◽  
Bacterial Cells

AbstractThe aim of this study was to determine the antibacterial property of extract derived from a part of the Jackfruit called ‘rag’, that is generally considered as fruit waste. Morpho-physical characterization of the Jackfruit rag extract (JFRE) was performed using gas-chromatography, where peaks indicative of furfural; pentanoic acid; and hexadecanoic acid were observed. In vitro biocompatibility of JFRE was performed using the MTT assay, which showed comparable cellular viability between extract-treated and untreated mouse fibroblast cells. Agar well disc diffusion assay exhibited JFRE induced zones of inhibition for a wide variety of laboratory and clinical strains of gram-positive and gram-negative bacteria. Analysis of electron microscope images of bacterial cells suggests that JFRE induces cell death by disintegration of the bacterial cell wall and precipitating intracytoplasmic clumping. The antibacterial activity of the JFREs was further validated in vivo using Shigella dysenteriae infected fly model, where JFRE pre-fed flies infected with S. dysenteriae had significantly reduced mortality compared to controls. JFRE demonstrates broad antibacterial property, both in vitro and in vivo, possibly by its activity on bacterial cell wall. This study highlights the importance of exploring alternative sources of antibacterial compounds, especially from plant-derived waste, that could provide economical and effective solutions to current challenges in antimicrobial therapy.

In vitro biological activity of synthesized silver nanoparticles using Myrtus extract

NanoNEXT ◽  
2021 ◽  
pp. 8-19
Author(s):  
Neda Mohamadi ◽  
Mohsen Doostmohammadi ◽  
Iraj Sharifi ◽  
Mehdi Bamorovat ◽  
Ahmad Khosravi ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Cell Lines ◽  
Human Cancer ◽  
Negative Control ◽  
Ros Production ◽  
Bacterial Cells ◽  
Human Cancer Cells ◽  
Ic50 Values ◽  
Mcf 7

This study aimed to synthesize and characterize silver nanoparticles (AgNPs) from M. communis laves, and determine their potential activity against human cancer cells as well as leishmanial and bacterial cells. The UV-visible spectroscopy showed an absorption peak at 430 nm wavelengths which is one of the characteristic features of AgNPs. The FESEM image showed irregular shape with a size range of 20-70 nm. MTT results in A172 and MCF-7 cell lines exposed to 5-240 g/mL for 48 hours revealed that M. communis-AgNPs were cytotoxic, with IC50 values of 93.2 g/mL for A172 cell lines and 89.1 g/mL for MCF-7 cell lines, respectively. DCFH-DA analysis showed that 24 h exposure to 25- 200 μg/mL concentrations of AgNPs significantly increased ROS production in cells that indicate oxidative stress induction by AgNPs. M. communis-AgNPs showed overexpression of BCL-2 and Bax genes compared with Glucantime®and negative control (p<0.001) as a potent leishmanicidal and bactericidal activity. The primary modes of action seem to be involved by promotion of the ROS production and up-regulation of BCL-2 and Bax against cancer cell lines. As a result, M. communis-AgNPs formulation should be regarded as a promising agent for potential anti-cancer, anti-leishmanial, and anti-bacterial drugs in therapeutic control programs

scholarly journals Mechanism of Action of the Antibiotic NXL101, a Novel Nonfluoroquinolone Inhibitor of Bacterial Type II Topoisomerases

2008 ◽  
Vol 52 (9) ◽  
pp. 3339-3349 ◽  
Author(s):  
Michael T. Black ◽  
Thérèse Stachyra ◽  
Denis Platel ◽  
Anne-Marie Girard ◽  
Monique Claudon ◽  
...  
Keyword(s):  
Point Mutations ◽  
Resistant Mutant ◽  
Fluoroquinolone Resistance ◽  
Topoisomerase Iv ◽  
Gram Positive Bacteria ◽  
New Class ◽  
Mutant Variant ◽  
Fluoroquinolone Antibiotics ◽  
Genes Encoding

ABSTRACT NXL101 is one of a new class of quinoline antibacterial DNA gyrase and topoisomerase IV inhibitors showing potent activity against gram-positive bacteria, including methicillin- and fluoroquinolone-resistant strains. NXL101 inhibited topoisomerase IV more effectively than gyrase from Escherichia coli, whereas the converse is true of enzymes from Staphylococcus aureus. This apparent target preference is opposite to that which is associated with most fluoroquinolone antibiotics. In vitro isolation of S. aureus mutants resistant to NXL101 followed by cloning and sequencing of the genes encoding gyrase and topoisomerase IV led to the identification of several different point mutations within, or close to, the quinolone resistance-determining region (QRDR) of GyrA. However, the mutations were not those that are most frequently associated with decreased sensitivity to quinolones. A fluoroquinolone-resistant mutant variant of gyrase generated in vitro was highly resistant to inhibition by the fluoroquinolones ciprofloxacin and moxifloxacin but remained fully susceptible to inhibition by NXL101. Two mutant gyrases constructed in vitro, with mutations in gyrA engineered according to those most frequently found in S. aureus strains resistant to NXL101, were insensitive to inhibition by NXL101 and had a diminished sensitivity to ciprofloxacin and moxifloxacin. Certain combinations of mutations giving rise to NXL101 resistance and those giving rise to fluoroquinolone resistance may be mutually exclusive.

scholarly journals Efficacy Bacteriophage in Removal Pseudomonas aeruginosa from Infectious Surfaces

2021 ◽  
Author(s):  
Golnar Rahimzadeh ◽  
Mohammad Sadegh Rezai
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Nosocomial Infection ◽  
Nosocomial Infections ◽  
Bacterial Cell ◽  
Cell Number ◽  
Biocontrol Agents ◽  
Hospital Environment ◽  
Bacterial Cells ◽  
Bacterial Cell Number

Nosocomial infections can be transmitted by contaminated hospital surfaces with resistant pathogens. conventional sanitations are not efficiently contributing to removing resistant pathogens. Bacteriophages suggest as decontaminating agents, safe, their selective ability to kill specific bacteria. This work aimed to assess the efficiency of a phage in removing Pseudomonas aeruginosa from different hard surfaces. The decontamination ability of phages w was tested in vitro against Pseudomonas aeruginosa strain. Cystoviridae Phages with titer (2 &times; 1012 PFU/mL) can efficiently reduce viable bacterial cells on contaminated surfaces. The treated surfaces with alcohol 70% and phage showed an evident drop of bacterial cell number from 1 h to 24 h. These results suggest that bacteriophages are biocontrol agents removing nosocomial infection pathogens transmitted by contaminated surfaces in the hospital environment.

Digestibility of rumen bacterial cell proteins in buffaloes and goats

1977 ◽  
Vol 88 (1) ◽  
pp. 237-239 ◽  
Author(s):  
D. N. Verma ◽  
U. B. Singh
Keyword(s):  
Single Dose ◽  
Bacterial Cell ◽  
Bacterial Cells ◽  
Streptococcus Bovis ◽  
Bacterial Protein ◽  
Formaldehyde Treatment

SUMMARYThe digestibility of protein of mixed whole rumen bacterial cells and Streptococcus bovis were determined in Bos bubalis and goats. The bacterial cells were labelled either with 35S or 14C in vitro incubation and were injected in a single dose into the rumen after protecting by formaldehyde treatment. Faeces were collected for 6 consecutive days and radioactivity excreted in the faeces was measured. The digestibility of bacterial protein ranged from 81·7 to 96·8% in both the species.

scholarly journals LYCOPENE PRODUCTION IN MYCOBACTERIUM SMEGMATIS BY EXPRESSION OF CRT GENES FROM MYCOBACTERIUM AURUM AND PROTECTIVE EFFECT OF LYCOPENE IN VIVO AND IN VITRO AGAINST UV RADIATION

2018 ◽  
Vol 10 (9) ◽  
pp. 49
Author(s):  
Oumaima Elamin ◽  
Marwa Chraibi ◽  
Saad Koraichi Ibnsouda ◽  
Mohammed Houssaini Iraqui
Keyword(s):  
Mycobacterium Smegmatis ◽  
Antioxidant Activities ◽  
Dry Weight ◽  
Bacterial Cells ◽  
Protective Properties ◽  
Lycopene Production ◽  
Mycobacterium Aurum ◽  
Layer Chromatography

Objective: The aim of the present study was to express in Mycobacterium smegmatis the clustered mycobacterial genes coding for lycopene synthesis and to investigate the protective properties of lycopene against ultraviolet (UV) irradiation.Methods: The genes, which encode the biogenesis of lycopene in Mycobacterium aurum A+, were introduced into Mycobacterium smegmatis by electroporation. The pigments produced were analyzed by thin layer chromatography, and the absorption spectra were determined. A survival test using UV irradiations was also performed.Results: The transformed Mycobacterium smegmatis were found to synthesize lycopene with important yield (1.41± 3.09 mg/g) and was more resistant to ultraviolet irradiation than non-pigmented strain (p<0.01). Furthermore, cells of M. smegmatis not transformed but coated with lycopene are more resistant to UV than those uncoated (p<0.01).Conclusion: M. smegmatis can form orange colonies on agar plates when it is transformed with the lycopene genes, and the transformants produces 1.41 mg/g (dry weight) of this carotene. Our findings strongly suggest that lycopene has antioxidant activities and prevent the lethal action of UV irradiation on bacterial cells in vivo and in vitro, and deserves further studies considering the amelioration of the production.

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