Multidrug efflux pumps function at the frontline to protect bacteria against antimicrobials by decreasing the intracellular concentration of drugs. This protective barrier consists of a series of transporter proteins, which are located in the bacterial cell membrane and periplasm and remove diverse extraneous substrates, including antimicrobials, organic solvents, toxic heavy metals, etc., from bacterial cells.
View Article and Find Full Text PDFThe evolution of resistance in to fluoroquinolones (FQs) under a broad range of sub-inhibitory concentrations (sub-MICs) has not been systematically studied. This study investigated the mechanism of resistance development in serovar Enteritidis (. Enteritidis) under sub-MICs of 1/128×MIC to 1/2×MIC of enrofloxacin (ENR), a widely used veterinary FQ.
View Article and Find Full Text PDFDue to the extensive application of antibiotics in medical and farming practices, the continued diversification and development of antimicrobial resistance (AMR) has attracted serious public concern. With the emergence of AMR and the failure to treat bacterial infections, it has led to an increased interest in searching for novel antibacterial substances such as natural antimicrobial substances, including microbial volatile compounds (MVCs), plant-derived compounds, and antimicrobial peptides. However, increasing observations have revealed that AMR is associated not only with the use of antibacterial substances but also with tolerance to heavy metals existing in nature and being used in agriculture practice.
View Article and Find Full Text PDFSheng Wu Gong Cheng Xue Bao
November 2020
Overuse of antibiotics in medical care and animal husbandry has led to the development of bacterial antimicrobial resistance, causing increasingly more health concern. In addition to genetic mutations and the formation of resistance, the various stresses bacteria encountered in the natural environment trigger their stress responses, which not only protect them from these stresses, but also change their tolerance to antimicrobials. The emergence of antimicrobial tolerance will inevitably affect the physiological metabolism of bacteria.
View Article and Find Full Text PDFBackground: The sweet potato weevil, Cylas formicarius, is the most serious pest of sweet potato worldwide. The molecular mechanism of sex pheromone recognition in C. formicarius has not been reported.
View Article and Find Full Text PDFTo establish a constitutive, high-efficiency expression and secretion system for Bacillus pumilus, the function of a promoter and the abilities of three signal peptides in B. pumilus DX01 were tested. F1, cloned from the rice epiphyte B.
View Article and Find Full Text PDFTo identify structural determinants of ligand binding in the glucagon receptor, eight receptor chimeras and additional receptor point mutants were prepared and studied. Amino acid residues 103-117 and 126-137 in the extracellular N-terminal tail and residues 206-219 and 220-231 in the first extracellular loop of the glucagon receptor were replaced with the corresponding segments of the glucagon-like peptide-1 receptor or the secretin receptor. Specific segments of both the N-terminal tail and the first extracellular loop of the glucagon receptor are required for hormone binding.
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