Use of the high‐affinity phosphate transporter gene, pstS , as an indicator for phosphorus stress in the marine diazotroph Crocosphaera watsonii ( Chroococcales , Cyanobacteria )

The marine diazotroph Crocosphaera watsonii provides fixed carbon (C) and nitrogen (N) to open-ocean regimes, where nutrient deficiency controls productivity. The growth of Crocosphaera can be limited by low phosphorus (P) concentrations in these oligotrophic environments. Biomarkers such as the high-affinity ABC transporter phosphate-binding gene, pstS, are commonly used to monitor when such organisms are under P stress; however,...