Plasticity of Total and Intracellular Phosphorus Quotas in Microcystis aeruginosa Cultures and Lake Erie Algal Assemblages

• Published in: Frontiers in microbiology 2012-01, Vol.3, p.3
• Main Authors: Saxton, Matthew A, Arnold, Robert J, Bourbonniere, Richard A, McKay, Robert Michael L, Wilhelm, Steven W
• Format: Article
• Language: English
• Subjects: Cyanobacteria; Microbiology; Microcystis; Phosphorus
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2012.00003

Blooms of the potentially toxic cyanobacterium Microcystis are common events globally, and as a result significant resources continue to be dedicated to monitoring and controlling these events. Recent studies have shown that a significant proportion of total cell-associated phosphorus (P) in marine phytoplankton can be surface adsorbed; as a result studies completed to date do not accurately report the P demands of these organisms. In this study we measure the total cell-associated and intracellular P as well as growth rates of two toxic strains of Microcystis aeruginosa Kütz grown under a range of P concentrations. The results show that the intracellular P pool in Microcystis represents a percentage of total cell-associated P (50-90%) similar to what has been reported for actively growing algae in marine systems. Intracellular P concentrations (39-147 fg cell(-1)) generally increased with increasing P concentrations in the growth medium, but growth rate and the ratio of total cell-associated to intracellular P remained generally stable. Intracellular P quotas and growth rates in cells grown under the different P treatments illustrate the ability of this organism to successfully respond to changes in ambient P loads, and thus have implications for ecosystem scale productivity models employing P concentrations to predict algal bloom events.