Phosphonate degradation through the C-P lyase pathway by a dinoflagellate-associated Mameliella alba enhances host growth under phosphate limitation.

Mameliella alba, a dinoflagellate-associated bacterium, can degrade phosphonates via the C-P lyase pathway and enhance host growth under phosphate-limited conditions.

• Why it matters: Phosphonates make up about 25% of the dissolved organic phosphorus in the ocean, but most eukaryotic phytoplankton cannot directly utilize them, limiting nutrient access in P-scarce environments.
• What they did: Researchers isolated and characterized strain DH-1, identified as Mameliella alba, which can grow on 2-AEP as the sole P source and upregulates C-P lyase genes under phosphate limitation and substrate induction, while promoting growth of the dinoflagellate Prorocentrum donghaiense when both DH-1 and 2-AEP are present.
• The result: This is the first demonstration that a dinoflagellate-associated bacterium can promote algal growth by degrading phosphonates to release phosphate, providing insights into mechanisms behind harmful algal bloom formation in P-limited marine environments.