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To remove phosphate accumulated in the soil and water, Acinetobacter lwoffi PO8 possessing a high ability to accumulate phosphate was isolated from a active sludge. Bacterium was cultured in the liquid medium containing 150 ㎍/mL of phosphate at 30℃ in different culture conditions to examine intracellular phosphate uptake. The initial pH in the range of 7.5∼8.5 was effective on the growth and phosphate uptake of the strain. Glycerol and arabinose used as a carbon sources showed 93 and 91% the phsphate uptake, respectively. Among the nitrogen sources, ammonium salt such as NH₄NO₃ and (NH₄)₂SO₄ was effectively utilized on the phosphate uptake compared with amino compounds. The rate of the phosphate uptake of NH₄NO₃ and (NH₄)₂SO₄, was 95 and 96%, respectively. The growth and phosphate uptake ability in the strain were significantly promoted when metal ions were added in the medium; Co^(2+), however, was not utilized by the strain. The capacity of phosphate uptake was enhanced to 10∼20% when arginine, methionine, or lysine was added. Using ^(32)P to examine the uptake pattern of intracellular phosphate, experiment result showed that polyphosphate was largely found in the fraction of intracellular inorganic phosphate of Acinetobacter lwoffi PO8.
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