The role of macronutrient minerals on the anaerobic trimethylamineoxyde reduction by an Achromobacter sp. isolated from fresh fish

The macronutrient minerals Na + , K + , Mg ++ , Ca ++ , and Fe ++ have been found to play an important role during the anaerobic TMAO reduction by the Achromobacter sp. The quantitative requirements for these ions are quite different. Most TMA is formed with 6 × 10 ‐3 M Mg ++ . The different requirements of the organism appear to be highly specific. The degree of TMAO reduction can not be restored if Na + or Mg ++ are respectively replaced by equimolar concentrations of respectively K + and Ca ++ . Iron seems also to play an important role Attention has been drawn to the interaction between Na + and K + , Mg ++ , Ca ++ , and Fe ++ . At suboptimum and optimum concentrations of Na + combined with suboptimum and optimum concentrations of K + , Mg ++ , Ca ++ , and Fe ++ , TMAO reduction was clearly enhanced. A maximal TMAO reduction takes place when 0.2 M Na + and 6 × 10 ‐3 M Mg ++ were added together in the basal medium.