POLYPHOSPHATE-PHOSPHATASE - INDUCTION, LOCALIZATION AND PURIFICATION FROM KLEBSIELLA SP LF-1202

A bacterial strain, Klebsiella sp. LF 1202, which was isolated from so il as an adenosine-assimilating bacterium (Ling, F. et al., Agric. Bio l. Chem., 55, 573-575, 1991), was able to use polyphosphate as a sourc e of phosphorus. The bacterium possessed a polyphosphate-phosphatase, an inducible enzyme located in a periplasmic space of the bacterium. T he enzyme was purified to a homogenous state on SDS-PAGE, and found to consist of four identical subunits with a molecular weight of 24,000. The enzyme exhibited activity towards tri-, tetra-, hexa-, octa-, and decapolyphosphate at pH 8.0, but not towards pyrophosphate and metaph osphate. The enzyme did not require metal ions for activity, but its a ctivity was strongly inhibited by Zn2+. Chelating agents such as EDTA and CDTA did not affect activity. Since the enzyme activity was not af fected by diisopropylfluorophosphate, serine residues do not seem to b e involved in the activity.