Publication: Molybdenum interacts directly with organic matter in sulfidic environments

Posted by on Dec 21, 2016 in Publication, Research | No Comments

Molybdenum is one of the most powerful elements used to track hydrogen sulfide and oxygen in the ocean from the geological record. Still, we have an incomplete understanding of the chemical removal pathway between ocean and sediments.  Sediments deposited under anoxic and sulfidic waters display tight correlations between their contents of molybdenum (Mo) and total organic matter  (TOC). Yet, association does not mean causation. Instead, we have a rather good mechanistic understanding of how Mo  would co-precipitate with iron sulfides (that likely are imbedded with organic matter).

In a new article in Geobiology, we document that molybdenum in aqueous sulfidic media directly adsorbs onto particulate organic matter, represented by dead and lysed sulfate reducing bacteria. Using synchrotron-based X-Ray Absorption Fine Structure analyses, we find that the produced molybdenum compounds have an chemical structure similar to those in most molybdenum enzymes.

Graphical Abstract