One hundred and seventy-three unrelated Listeria monocytogenes strains isolated from humans, animals, the environment, and food were analyzed for the presence of plasmids. Extrachromosomal DNA was found in 28% of the strains. Plasmid DNA was extracted more frequently from L. monocytogenes serogroup 1 strains (35%) than from serogroup 4 strains (15%). Among strains from food and the environment, 40% and 29%, respectively, harbored plasmids, whereas only 13% of the strains from humans and animals with listeriosis bore plasmids. We also investigated the susceptibility of 90 strains to seven antibiotics and four heavy-metal salts. No antibiotic resistance could be detected, but 95.3% of the plasmid-positive strains and only 12.7% of the plasmid-negative strains were resistant to cadmium. The plasmid-determined genetic basis of cadmium resistance was proven by conjugation between strains of L. monocytogenes and by cure of the plasmid. This is the first time that plasmids of L. monocytogenes have been shown to be associated with cadmium resistance.
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http://dx.doi.org/10.1128/aem.58.9.3183-3186.1992 | DOI Listing |
Environ Res
January 2025
Chinese Academy of Sciences Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China; Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China. Electronic address:
Both antibiotics and heavy metals exert significant selection pressures on antibiotic-resistance genes (ARGs). This study aimed to investigate the co-selection effects of doxycycline (DC) and cadmium (Cd) on ARGs in constructed wetlands (CWs). The results demonstrated that under antibiotic and heavy metal co-selection pressures, single high concentration DC/Cd or double high, relative abundances of metagenomics assembled genomes all reached 55.
View Article and Find Full Text PDFToxicol Appl Pharmacol
January 2025
College of Pharmacy, Institute of Pharmaceutical Science and Technology, Hanyang University ERICA Campus, Ansan, South Korea. Electronic address:
Cadmium (Cd) is a heavy metal that is a major hazardous environmental contaminant, ubiquitously present in the environment. Cd exposure has been closely associated with an increased prevalence and severity of neurological and cardiovascular diseases (CVD). The blood-brain barrier (BBB) plays a crucial role in protecting the brain from external environmental factors.
View Article and Find Full Text PDFMicrobiol Resour Announc
January 2025
Department of Natural Sciences, Northwest Missouri State University, Maryville, Missouri, USA.
Soil bacteria were isolated from the Tar Creek Superfund site in the presence of cadmium. Eight of these strains belong to the genus , whereas one strain belongs to the genus . Here, we report drafts of their genome sequences and highlight cadmium-resistance genes required in an exceptionally contaminated environment.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
College of Animal Science and Technology, Southwest University, Chongqing 402460, China; Chongqing Key Laboratory of Herbivore Science, Chongqing 402460, China. Electronic address:
Cadmium (Cd) is recognized as one of the most toxic heavy metal in the environment that causes pronounced phytotoxicity. This study investigated the physiological and biochemical responses and detoxification mechanisms of Hemarthria compressa under various concentrations of Cd stress (0, 30, 60, 90, and 270 mg·kg). Our research findings indicate that the growth and photosynthetic capacity of H.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
College of Horticulture and Landscape Architecture, Tianjin Agricultural University, Tianjin, 300392, China.
Citrullus lanatus is an important vegetable crop, but it is heavily polluted by cadmium. In this study, we used C. Lanatus as experimental material to investigate effects of different concentrations (0, 50, 100, 200, 400 µmolL) of exogenous melatonin, and grafting on the physiological growth index and anatomical structure of seedlings were studied by simulating Cd (180 mg L) stress environment.
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