Search results for " BAC"
showing 10 items of 2829 documents
A New Water-Soluble Bactericidal Agent for the Treatment of Infections Caused by Gram-Positive and Gram-Negative Bacterial Strains
2020
Grapefruit and lemon pectin obtained from the respective waste citrus peels via hydrodynamic cavitation in water only are powerful, broad-scope antimicrobials against Gram-negative and -positive bacteria. Dubbed IntegroPectin, these pectic polymers functionalized with citrus flavonoids and terpenes show superior antimicrobial activity when compared to commercial citrus pectin. Similar to commercial pectin, lemon IntegroPectin determined ca. 3-log reduction in Staphylococcus aureus cells, while an enhanced activity of commercial citrus pectin was detected in the case of Pseudomonas aeruginosa cells with a minimal bactericidal concentration (MBC) of 15 mg mL&minus
Enhanced emergence of antibiotic-resistant pathogenic bacteria after in vitro induction with cancer chemotherapy drugs.
2019
International audience; BACKGROUND:Infections with antibiotic-resistant pathogens in cancer patients are a leading cause of mortality. Cancer patients are treated with compounds that can damage bacterial DNA, potentially triggering the SOS response, which in turn enhances the bacterial mutation rate. Antibiotic resistance readily occurs after mutation of bacterial core genes. Thus, we tested whether cancer chemotherapy drugs enhance the emergence of resistant mutants in commensal bacteria.METHODS:Induction of the SOS response was tested after the incubation of Escherichia coli biosensors with 39 chemotherapeutic drugs at therapeutic concentrations. The mutation frequency was assessed after …
New Synthetic Nitro-Pyrrolomycins as Promising Antibacterial and Anticancer Agents
2020
: Pyrrolomycins (PMs) are polyhalogenated antibiotics known as powerful biologically active compounds, yet featuring high cytotoxicity. The present study reports the antibacterial and antitumoral properties of new chemically synthesized PMs, where the three positions of the pyrrolic nucleus were replaced by nitro groups, aiming to reduce their cytotoxicity while maintaining or even enhancing the biological activity. Indeed, the presence of the nitro substituent in diverse positions of the pyrrole determined an improvement of the minimal bactericidal concentration (MBC) against Gram-positive (i.e., Staphylococcus aureus) or -negative (i.e., Pseudomonas aeruginosa) pathogen strains as compare…
New Genes Involved in Mild Stress Response Identified by Transposon Mutagenesis in Lactobacillus paracasei
2018
International audience; Lactic acid bacteria (LAB) are associated with various plant, animal, and human niches and are also present in many fermented foods and beverages. Thus, they are subjected to several stress conditions and have developed advanced response mechanisms to resist, adapt, and grow. This work aimed to identify the genes involved in some stress adaptation mechanisms in LAB. For this purpose, global reverse genetics was applied by screening a library of 1287 Lactobacillus paracasei transposon mutants for mild monofactorial stresses. This library was submitted independently to heat (52 degrees C, 30 min), ethanol (170 g.L-1, 30 min), salt (NaCl 0.8 M, 24 h), acid (pH 4.5, 24 h…
Low sensitivity of the MPT64 identification test to detect lineage 5 of the Mycobacterium tuberculosis complex
2018
Abstract: Purpose. Differentiation of the Mycobacterium tuberculosis complex (MTBc) from non-tuberculous mycobacteria (NTM) is important for tuberculosis diagnosis and is a prerequisite for reliable phenotypic drug-resistance testing. We evaluated the performance of the rapid MPT64 antigen identification test for the detection of Mycobacterium africanum lineage 5 (MAF L5). Methodology. Smear-positive tuberculosis patients' sputa were included prospectively. Culture was performed on Lowenstein-Jensen medium and, when positive, the MPT64 test and the classical para-nitro benzoic acid susceptibility and heat-labile catalase (PNB/catalase) identification tests were performed. The MPT64 test was…
Large genomics datasets shed light on the evolution of the Mycobacterium tuberculosis complex
2019
Review: 5 páginas, 1 figura
Resistance to third-generation cephalosporins in Escherichia coli in the French community: The times they are a-changin'?
2020
Since the early 2000s, Escherichia coli resistance to third-generation cephalosporins (3GCs) has been increasing in all European countries, mainly due to the spread of extended spectrum β-lactamases (ESBLs). Here we present a retrospective study that combines resistance of E. coli to 3GCs and quinolones with data on antibiotic use in the community in a region of Northeastern France.Since 2012, an observational surveillance of antimicrobial resistance and antibiotic use in the community was conducted: data on antimicrobial resistance in E. coli isolates were collected from 11 private laboratories, and consumption data were collected from the three main healthcare insurances.A significant dec…
Characterization of ESBL-producing enterobacteria from fruit bats in an unprotected area of Makokou, Gabon.
2020
In Gabon, terrestrial mammals of protected areas have been identified as a possible source of antibiotic-resistant bacteria. Some studies on antibiotic resistance in bats have already been carried out. The main goal of our study was to detect extended-spectrum beta-lactamases (ESBLs) that are produced by enterobacteria from bats in the Makokou region in Gabon. Sixty-eight fecal samples were obtained from 68 bats caught in the forests located 1 km from the little town of Makokou. After culture and isolation, 66 Gram-negative bacterial colonies were obtained. The double-disk diffusion test confirmed the presence of ESBLs in six (20.69%) Escherichia coli isolates, four (13.79%) Klebsiella pneu…
Using GFP-Tagged Escherichia coli to Investigate the Persistence of Fecal Bacteria in Vegetated Wetlands: An Experimental Approach
2020
The contamination of surface water by pathogenic bacteria of human origin is an important public health issue. Wetlands can be contaminated with fecal bacteria by water originating from different sources, such as wastewater treatment plants and agriculture. Escherichia coli is a commensal of the human gut flora and the major indication of fecal contamination in surface water. Little is known about the association between fecal bacteria and submerged macrophytes and how this may influence the water quality. We questioned whether macrophytes enhance or inhibit the bacterial growth in wetlands. For this purpose, we grew four different species of macrophytes (Mentha aquatica, Baldellia ranuncul…
Endophytic Bacterial Community Structure and Function of Herbaceous Plants From Petroleum Hydrocarbon Contaminated and Non-contaminated Sites
2018
Bacterial endophytes (BEs) are non-pathogenic residents of healthy plant tissues that can confer benefits to plants. Many Bacterial endophytes have been shown to contribute to plant growth and health, alleviation of plant stress and to in-planta contaminant-degradation. This study examined the endophytic bacterial communities of plants growing abundantly in a heavily hydrocarbon contaminated site, and compared them to those found in the same species at a non-contaminated. We used culture- dependent and independent methods to characterize the community structure, hydrocarbon degrading capabilities, and plant growth promoting traits of cultivable endophytes isolated from Achillea millefolium,…