Paulo Lara M, Hidayat Mohamad R, Moretti Giulio, Stams Alfons J M, Sousa Diana Z
Laboratory of Microbiology, Wageningen University & Research, Wageningen, The Netherlands.
Laboratory of Microbiology, MESVA Department, University of L'Aquila, Via Vetoio Coppito (AQ), Italy.
Biotechnol Appl Biochem. 2020 Sep;67(5):744-750. doi: 10.1002/bab.1925. Epub 2020 May 12.
Methanogens are responsible for the last step in anaerobic digestion (AD), in which methane (a biofuel) is produced. Some methanogens can cometabolize chlorinated pollutants, contributing for their removal during AD. Methanogenic cofactors involved in cometabolic reductive dechlorination, such as F and cobalamin, contain metal ions (nickel, cobalt, iron) in their structure. We hypothesized that the supplementation of trace metals could improve methane production and the cometabolic dechlorination of 1,2-dichloroethene (DCE) by pure cultures of Methanosarcina barkeri. Nickel, cobalt, and iron were added to cultures of M. barkeri growing on methanol and methanol plus DCE. Metal amendment improved DCE dechlorination to vinyl chloride (VC): assays with 20 µM of Fe showed the highest final concentration of VC (5× higher than in controls without Fe ), but also in assays with 5.5 µM of Co and 5 µM of Ni VC formation was improved (3.5-4× higher than in controls without the respective metals). Dosing of metals could be useful to improve anaerobic removal of chlorinated compounds, and more importantly decrease the detrimental effect of DCE on methane production in anaerobic digesters.
产甲烷菌负责厌氧消化（AD）的最后一步，在此过程中会产生甲烷（一种生物燃料）。一些产甲烷菌可以共代谢氯化污染物，有助于在厌氧消化过程中去除这些污染物。参与共代谢还原脱氯的产甲烷辅因子，如F和钴胺素，其结构中含有金属离子（镍、钴、铁）。我们推测，添加微量金属可以提高巴氏甲烷八叠球菌纯培养物的甲烷产量以及1,2 - 二氯乙烯（DCE）的共代谢脱氯能力。将镍、钴和铁添加到以甲醇以及甲醇加DCE为底物生长的巴氏甲烷八叠球菌培养物中。金属添加改善了DCE向氯乙烯（VC）的脱氯效果：用20 μM铁进行的试验显示出最高的VC终浓度（比无铁对照高5倍），但在使用5.5 μM钴和5 μM镍的试验中，VC的生成也得到了改善（比无相应金属的对照高3.5 - 4倍）。添加金属可能有助于改善厌氧消化池中氯化化合物的去除，更重要的是降低DCE对甲烷产生的不利影响。
