Centro de Biotecnologia e Química Fina-CBQF, EscolaSuperior de Biotecnologia, Universidade Católica Portuguesa, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal.
Biodegradation. 2012 Sep;23(5):653-62. doi: 10.1007/s10532-012-9541-1.
This study focuses on the biodegradation of difluorobenzenes (DFBs), compounds commonly used as intermediates in the industrial synthesis of various pharmaceutical and agricultural chemicals. A previously isolated microbial strain (strain F11), identified as Labrys portucalensis, able to degrade fluorobenzene (FB) as sole carbon and energy source, was tested for its capability to degrade 1,2-, 1,3- and 1,4-DFB in batch cultures. Strain F11 could use 1,3-DFB as a sole carbon and energy source, with quantitative release of fluoride, but 1,4-DFB was only degraded and defluorinated when FB was supplied simultaneously. Growth of strain F11 with 0.5 mM of 1,3-DFB led to stoichiometric release of fluoride ion. The same result was obtained in cultures fed with 1 mM of 1,3-DFB or 0.5 mM of 1,4-DFB, in the presence of 1 mM of FB. No growth occurred with 1,2-DFB as substrate, and degradation of FB was inhibited when supplied simultaneously with 1,2-DFB. To our knowledge, this is the first time biodegradation of 1,3-DFB as a sole carbon and energy source, and cometabolic degradation of 1,4-DFB, by a single bacterium, is reported.
本研究聚焦于二氟苯（DFBs）的生物降解，DFBs 是工业合成各种医药和农用化学品的常用中间体。先前分离出的微生物菌株（菌株 F11）被鉴定为 Labrys portucalensis，能够以氟苯（FB）作为唯一的碳源和能源进行降解，我们对其降解 1,2-、1,3-和 1,4-DFB 的能力进行了分批培养测试。菌株 F11 可以将 1,3-DFB 作为唯一的碳源和能源使用，并定量释放氟化物，但只有当同时提供 FB 时，1,4-DFB 才会被降解和脱氟。以 0.5mM 的 1,3-DFB 为生长基质时，菌株 F11 的生长会导致氟离子的化学计量释放。当以 1mM 的 1,3-DFB 或 0.5mM 的 1,4-DFB 为生长基质，并同时提供 1mM 的 FB 时，会得到相同的结果。以 1,2-DFB 作为底物时不会发生生长，而当同时提供 FB 时，FB 的降解会受到抑制。据我们所知，这是首次报道单一细菌以 1,3-DFB 作为唯一碳源和能源进行生物降解，以及 1,4-DFB 的共代谢降解。
