Phosphate levels and expression of phosphoribosylpyrophosphate synthetase isozymes in suspension-cultured Arabidopsis thaliana cells

The activities of phosphate-dependent and phosphate-independent phosphoribosyltransferase synthetase (EC 2.7.6.1), and the expression of four genes encoding isoforms of this enzyme, were determined in cultured Arabidopsis thaliana cells. The role of plant specific phosphate-independent isoforms is discussed.