Now, Israeli biologists say that while the science community has already known that the recognizable smell is caused by the molecule dimethylsulfide (DMS), which algae produce in large amounts, they’ve discovered the algal enzymes responsible for forming DMS.
In a study recently published in Science magazine, the Israeli researchers say enzyme Alma1 — a tetrameric, redox-sensitive enzyme of the aspartate racemase superfamily — is responsible for converting the molecule dimethylsulfoniopropionate (DMSP) into DMS in the algae Emiliania huxleyi.
“We identified and characterized Alma1, a DMSP lyase from the bloom-forming algae Emiliania huxleyi,” the researchers wrote in the abstract to their study. “Alma1 is a tetrameric, redox-sensitive enzyme of the aspartate racemase superfamily. Recombinant Alma1 exhibits biochemical features identical to the DMSP lyase in E. huxleyi, and DMS released by various E. huxleyi isolates correlates with their Alma1 levels. Sequence homology searches suggest that Alma1 represents a gene family present in major, globally distributed phytoplankton taxa and in other marine organisms.”
Citing Alma1’s presence in other marine organisms, such as seaweeds that also release DMS, it makes sense why so many plants along the seashore have that distinctive seaside smell.