Antibacterial Activity and Mechanism of Coenzyme Q0 Against Escherichia coli.

Coenzyme Q0 (CoQ0) is a natural compound found in Antrodia cinnamomea, which has a variety of biological activities. Here, the antibacterial activity and possible antibacterial mechanism of CoQ0 against Escherichia coli were investigated. The antibacterial effect was evaluated by determining minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values, and by assessing bacterial survival and the effect on the growth of E. coli after CoQ0 treatment in Luria-Bertani (LB) broth. To reveal the antibacterial mechanism of CoQ0, changes in intracellular adenosine triphosphate (ATP) concentration, membrane potential, and bacterial protein content, as well as effects on cell morphology and membrane integrity, were investigated. Both the MICs and MBCs of CoQ0 against E. coli were 0.1 mg/mL. After treatment of E. coli (6.5 log colony-forming units/mL) with 0.1 mg/mL of CoQ0 in LB broth for 3 h, the number of viable cells dropped below the detection limit. In addition, CoQ0 treatment resulted in the reduction in intracellular ATP concentration, cell membrane hyperpolarization, decreased bacterial protein concentrations, and damage to cell membrane integrity and cellular morphology. These results indicated that CoQ0 has effective antibacterial activity against E. coli, suggesting potential applications in food industry safety.

High Carriage of Extended-Spectrum, Beta Lactamase-Producing, and Colistin-Resistant Enterobacteriaceae in Tibetan Outpatients with Diarrhea.

Antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) have been detected in human-impacted habitats, especially in densely populated cities. The Qinghai-Tibet Plateau is located far from the heavily populated regions of China, and Tibetan residents have distinct dietary habits and gut microbes. Antibiotic-resistance monitoring in the Tibetan population is rare. Here, we collected stool samples from Tibetan outpatients with diarrhea. From 59 samples, 48 antibiotic-resistant Enterobacteriaceae isolates were obtained, including 19 extended-spectrum beta lactamase (ESBL)-producing isolates from 16 patients and 29 polymyxin-resistant isolates from 22 patients. Either ESBL or mcr genes were found in 17 Escherichia coli isolates, approximately 58.8% of which were multidrug-resistant, and ten incompatible plasmid types were found. The gene blaCTX-M was a common genotype in the ESBL-producing E. coli isolates. Four E. coli isolates contained mcr-1. The same mcr-1-carrying plasmid was found in distinct E. coli isolates obtained from the same sample, thus confirming horizontal transmission of mcr-1 between bacteria. Genomic clustering of E. coli isolates obtained from Lhasa, with strains from other regions providing evidence of clone spreading. Our results reveal a strong presence of ARB and ARGs in Tibetan outpatients with diarrhea, implying that ARB and ARGs should be monitored in the Tibetan population.