PHOSPHATASE PRODUCTION BY A CITROBACTER SP GROWING IN BATCH CULTURE AND USE OF BATCH CULTURES TO INVESTIGATE SOME LIMITATIONS IN THE USE OF POLYACRYLAMIDE GEL-IMMOBILIZED CELLS FOR PRODUCT RELEASE

Phosphatase production by a Citrobacter sp. increased during exponential growth but was transiently repressed by glucose in medium containing glycerol 2-phosphate as the sole phosphorus source. In inorganic phosphate medium, phosphatase production was enhanced by carbon starvation, but was inhibited by an excess of glucose, or in glycerol-sufficient cultures upon entry into stationary phase. This was prevented by the provision of glycerol 2-phosphate as the phosphorus source. The data are consistent with known multiple regulatory patterns for other bacterial acid phosphatases and would account for interbatch variations in phosphatase titer. Such variation can be employed to prepare batches of cells of different phosphatase titer which can be used as tools to investigate the substrate diffusional limitations involved in the use of polyacrylamide gel-immobilized cells for phosphate release.