COMPARISON OF 2 METHODS FOR MEASURING PHOSPHATE-UPTAKE BY MONOCHRYSIS-LUTHERI DROOP GROWN IN CONTINUOUS CULTURE

Two methods for measuring phosphate uptake by phosphate-limited continuous cultures of Monochrysis lutheri Droop are found to yield comparable results. Data from both isotopic tracer (33P) and disappearance experiments strongly support a Michaelis- Menten-type hyperbolic relationship between instantaneous uptake rate and ambient phosphate concentration. The data show no systematic linear trend in either the maximum uptake rate per cell or its associated half saturation constant with pre-conditioning steady state growth rate; a weak non-linear trend with pre-conditioning may, however, be present in the maximum uptake rate with an apparent maximum at intermediate growth rates. © 1979.