Dissolved organic phosphorus utilization by phytoplankton reveals preferential degradation of polyphosphates over phosphomonoesters ...

• Main Authors: Diaz, Julia M., Holland, Alisia, Sanders, James G., Bulski, Karrie, Mollett, Douglas, Chou, Chau-Wen, Phillips, Dennis, Tang, Yuanzhi, Duhamel, Solange
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Columbia University 2018
• Subjects: Geochemistry; FOS: Earth and related environmental sciences; Marine biology; Phytoplankton; Organophosphorus compounds; Polyphosphates; Phosphorus in animal nutrition; North Atlantic
• Online Access: https://dx.doi.org/10.7916/d8-crnq-4z64; https://academiccommons.columbia.edu/doi/10.7916/d8-crnq-4z64

The nutritionally available pool of dissolved organic phosphorus (DOP) supports marine primary productivity in a range of ocean ecosystems but remains poorly resolved. Here, the relative lability of model phosphorus (P) compounds representing the major P(V) bond classes of marine DOP – phosphomonoesters (P-O-C) and phosphoanhydrides (P-O-P) – was assessed in diatom cultures of the genus Thalassiosira, as well as coastal field sites of the western North Atlantic. In diatom samples, maximum enzymatic hydrolysis rates revealed that the P-anhydride bonds of inorganic tripolyphosphate (3poly-P), followed by the P-anhydride bonds of adenosine 5′-triphosphate (ATP), were preferentially degraded relative to the P-monoesters adenosine 5′-monophosphate (AMP) and 4-methylumbelliferone phosphate (MUF-P). Consistent with these rate measurements, targeted proteomics analysis demonstrated that the underlying phosphatase diversity present in diatom samples was dominated by P-anhydride degrading enzymes (inorganic ...