Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1039/d3cp01055d
Titel (primär) Mechanistic insight into the Dehalococcoides-mediated reductive dechlorination of polychlorinated biphenyls
Autor Zhang, S.; Ouyang, X.; Xia, X.; Wen, W.; Adrian, L.; Schüürmann, G.
Quelle Physical Chemistry Chemical Physics
Erscheinungsjahr 2023
Department OEC; UBT
Band/Volume 25
Heft 22
Seite von 15193
Seite bis 15199
Sprache englisch
Topic T7 Bioeconomy
T9 Healthy Planet
Supplements https://www.rsc.org/suppdata/d3/cp/d3cp01055d/d3cp01055d1.pdf
Keywords Strain CBDB1; dehalogenation; regioselectivity; organohalides; DFT
Abstract

Microbial reductive dechlorination provides a green and highly desirable approach to address the pollution raised by the substantial legacies of polychlorinated biphenyls (PCBs) in soil, sediment, and underground water. It has been shown that the reaction event is catalyzed by supernucleophilic cob(I)alamin housed in reductive dehalogenases (RDases). However, the mechanism still remains elusive. Herein, we unravel the mechanism via quantum chemical calculations, considering a general model of RDase and the dechlorination regioselectivity of two representative PCB congeners, 234-236-CB and 2345-236-CB. The B12-catalzyed reductive dechlorination of PCBs starts with the formation of a reactant complex, followed by a proton-coupled two-electron transfer (PC-TET) and a subsequent single-electron transfer (SET). The PC-TET yields a cob(III)alamin-featured intermediate, which is quickly reduced by the latter SET fueled by significant energetic benefits (100 kcal mol−1). It rationalizes the exclusive detection and characterization of cob(I/II)alamins in RDase-mediated dehalogenation experiments. The determined mechanism successfully reproduces the experimental dechlorination regioselectivity and reactivity, as observed with Dehalococcoides mccartyi strain CG1.

dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=27111
Zhang, S., Ouyang, X., Xia, X., Wen, W., Adrian, L., Schüürmann, G. (2023):
Mechanistic insight into the Dehalococcoides-mediated reductive dechlorination of polychlorinated biphenyls
Phys. Chem. Chem. Phys. 25 (22), 15193 - 15199 10.1039/d3cp01055d