Advances in reductive dehalogenation of halogenated organic compounds by anaerobic microorganisms in the marine environment

Abstract:

Halogenated organic compounds (HOCs) have gained increasing attention due to their potential toxicity, environmental persistence, and bioconcentration. The marine environment is a major source and sink of HOCs, not only accumulating large amounts of anthropogenic HOCs but also containing a wide range of naturally produced HOCs. Microbial reductive dehalogenation is a key strategy for the remediation of HOCs pollution, in which organohalide-respiring bacteria (OHRB) play a pivotal role in the bioremediation and geochemical cycling of HOCs. This article provides an overview of the sources and distribution of HOCs in the marine environment as well as the mechanisms of reductive dehalogenation by anaerobic microorganisms. It systematically reviews the research progress in reductive dehalogenating bacteria that have been isolated from the marine environment and the reductive dehalogenases, aiming to provide a reference for the bioremediation of HOCs in the marine environment and lay a theoretical foundation for clarifying the biogeochemical cycle of halogens in the marine environment. Additionally, this article explores the differences in the properties of marine and terrestrial dehalogenating bacteria and their potential connections, which are important for elucidating their evolution and environmental adaptation in different ecosystems.

Key words:halogenated organic compounds (HOCs);marine environment;organohalide-respiring bacteria;reductive dehalogenase