Trichloroethylene (TCE), a common groundwater contaminant, is a suspected carcinogen that is highly resistant to aerobic biodegradation. An aerobic, methane-oxidizing bacterium was isolated that degrades TCE in pure culture at concentrations commonly observed in contaminated groundwater. Strain 46-1, a type I methanotrophic bacterium, degraded TCE if grown on methane or methanol, producing CO(2) and water-soluble products. Gas chromatography and C radiotracer techniques were used to determine the rate, methane dependence, and mechanism of TCE biodegradation. TCE biodegradation by strain 46-1 appears to be a cometabolic process that occurs when the organism is actively metabolizing a suitable growth substrate such as methane or methanol. It is proposed that TCE biodegradation by methanotrophs occurs by formation of TCE epoxide, which breaks down spontaneously in water to form dichloroacetic and glyoxylic acids and one-carbon products.
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http://dx.doi.org/10.1128/aem.54.4.951-956.1988 | DOI Listing |
Chemosphere
January 2025
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China.
Trichloroethylene (TCE) is a common chlorinated hydrocarbon contaminant in soil and groundwater, and reductive dechlorination is a biological remediation. However, the TCE reductive dechlorination often stagnates in the stage of cis-1,2-dichloroethylene (cDCE) and chloroethylene (VC). Anaerobic/aerobic sequential degradation provides a new approach for the complete detoxification of TCE, while there has been no systematic summary of bacteria, enzymes, and pathways in the synergistic process.
View Article and Find Full Text PDFEnviron Sci Process Impacts
January 2025
Ruđer Bošković Institute, Division for Marine and Environmental Research, Bijenička cesta 54, Zagreb, Croatia.
Technology-critical elements (TCEs) refer to the elements that play an important role in many emerging technologies and the production of advanced materials, and these include lanthanides, tungsten and vanadium. Actinides, Tl, and Pb, which also belong to TCEs, are abundantly used in power generation, industrial applications, and modern agricultural practices. The information on the influence of these elements on the aquatic environment and biota is still rather scarce.
View Article and Find Full Text PDFChemosphere
February 2025
Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
While vegetable uptake of traditional metal contaminants is a well-studied pathway to human exposure and risk, a paucity of information exists on the uptake of emerging metal contaminants. This study evaluated the uptake of the Technology-critical elements (TCEs) gallium (Ga), germanium (Ge), niobium (Nb), tantalum (Ta), thallium (Tl), and rare earth elements (REEs) into lettuce cultivated in 21 European urban soils. For comparison, the uptake of cadmium (Cd) was also analysed.
View Article and Find Full Text PDFOncoimmunology
December 2025
Cancer Immunotherapy Unit (UNICA), Department of Immunology, Hospital Universitario12 de Octubre, Madrid, Spain.
Despite recent advances in immunotherapy against B cell malignancies such as BCMA (B cell maturation antigen) and CD19-targeted treatments using soluble T cell-engaging (TCE) antibodies or chimeric antigen receptor T cells (CAR-T), there is still an important number of patients experiencing refractory/relapsed (R/R) disease. Approaches to avoid tumor-intrinsic mechanisms of resistance such as immune pressure-mediated antigen downmodulation, are being broadly investigated. These strategies include BCMA/CD19 dual-targeting therapies, which may be of particular interest to patients with B cell lymphoma and multiple myeloma, where a specific double-positive immature subpopulation is commonly associated with poor prognosis and poor response to current treatments.
View Article and Find Full Text PDFAdv Mater
December 2024
Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119074, Singapore.
The unprecedented success of mRNA vaccines against COVID-19 has inspired scientists to develop mRNA vaccines for cancer immunotherapy. However, using nucleoside modified mRNA as vaccine, though evading innate immune toxicity, diminishes its therapeutic efficacy for cancers. Here, we report a polyvalent stimulator of interferon genes (STING) activating polymer (termed as PD) to bolster the immunogenicity of mRNA vaccine.
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