IN-VITRO CHARACTERIZATION OF A PHOSPHATE STARVATION-INDEPENDENT CARBON-PHOSPHORUS BOND-CLEAVAGE ACTIVITY IN PSEUDOMONAS-FLUORESCENS 23F

A novel, metal-dependent, carbon-phosphorus bond cleavage activity, pr ovisionally named phosphonoacetate hydrolase, was detected in crude ex tracts of Pseudomonas fluorescens 23F, an environmental isolate able t o utilize phosphonoacetate as the sole carbon and phosphorus source. T he activity showed unique specificity toward this substrate; its organ ic product, acetate, was apparently metabolized by the glyoxylate cycl e enzymes of the host cell. Unlike phosphonatase, which was also detec ted in crude extracts of P. fluorescens 23F, phosphonoacetate hydrolas e was inducible only in the presence of its sole substrate and did not require phosphate starvation.