运用硫铵沉淀、阴离子交换柱层析、凝胶过滤、ＦＰＬＣ和活性电泳等技术，从缺磷条件下生长的番茄根抽提物中分离提纯了植酸酶．该酶是分子量约为８２ｋＤ的亚基组成的二聚体，等电点５．５，最适ｐＨ为４．３，对植酸钠具有很高亲和力（Ｋｍ＝３８μｍｏｌ／Ｌ）．番茄植酸酶活性受无机磷酸、钼和氟化物强烈抑制．氨基酸组成分析表明，该酶谷氨酸、天冬氨酸和甘氨酸含量较高． Phytase was isolated and purified from tomato root extracts grown under phosphorus deficiency using ammonium sulfate precipitation, anion exchange column chromatography, gel filtration, FPLC and electrophoresis. The enzyme is a dimer composed of subunits with a molecular weight of about 82 kD. The isoelectric point is 5.5 and the optimum pH is 4.3. It has a high affinity for sodium phytate (Km = 38 μmol / L). Tomato phytase activity is strongly inhibited by inorganic phosphate, molybdenum and fluoride. Amino acid composition analysis showed that the enzyme glutamic acid, aspartic acid and glycine content is higher.