Abstract Marine sponges contain diverse brominated compounds as secondary metabolites and the sponge habitat appears to enrich for a population of anaerobic dehalogenating bacteria. Hence, there is interest in understanding how these natural and anthropogenic compounds are degraded in the marine environment. Compound specific isotope analysis (CSIA) is a useful tool to monitor and to quantify the degradation and fate of aquatic pollutants. The objective of this study was to evaluate whether reductive dehalogenation of brominated phenols by sponge-associated bacteria, including Desulfoluna spongiiphila, can be monitored by CSIA. Debromination of 2,6-dibromophenol to phenol by sponge-associated cultures resulted in measurable stable carbon isotope fractionation. All sponge-associated cultures showed similar isotopic enrichment factors (e). The e values for two independent sponge-derived dehalogenating cultures were −3.1 ± 1.5‰, and −3.0 ± 0.3‰, and that of sponge associated sediment cultures −2.0 ± 0.3‰. Thus, we demonstrate that reductive debromination of 2,6-dibromophenol resulted in measurable carbon isotope fractionation and that CSIA can be used to assess reductive debromination and to monitor and estimate in vivo dehalogenation in a sponge animal.

中文翻译：

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海绵相关厌氧菌与碳同位素分馏耦合的还原脱溴

摘要海洋海绵含有多种溴化化合物作为次级代谢物，海绵栖息地似乎富含厌氧脱卤细菌。因此，有兴趣了解这些天然和人为化合物如何在海洋环境中降解。化合物特定同位素分析 (CSIA) 是监测和量化水生污染物降解和归宿的有用工具。本研究的目的是评估是否可以通过 CSIA 监测海绵相关细菌（包括 Desulfoluna spongiiphila）对溴化酚的还原脱卤作用。通过海绵相关培养物将 2,6-二溴苯酚脱溴为苯酚导致可测量的稳定碳同位素分馏。所有与海绵相关的培养物都显示出相似的同位素富集因子 (e)。两种独立的海绵衍生脱卤培养物的 e 值分别为 -3.1 ± 1.5‰ 和 -3.0 ± 0.3‰，海绵相关沉积物培养物的 e 值为 -2.0 ± 0.3‰。因此，我们证明 2,6-二溴苯酚的还原脱溴会导致可测量的碳同位素分馏，并且 CSIA 可用于评估还原脱溴并监测和估计海绵动物的体内脱卤。