Purification and Properties of Acid Phosphatase from Plump and Shriveled Seeds of Triticale

Abstract

ABSTRACrA major triticale (X Triticosecalk Wittmack) endosperm acid phosphatase (EC 3.1.2.2) (APase) from sib-lines producing plump and shriveled seed was purified 140-and 2304fold to a specific activity of 94 and 153 micromoles per minute per miligram protein respectively, by ammonium sulfate fractionation, ion-exchange chromatography, chromatofocusing, affinity column chromatography, and gel filtration. The purified enzyme from both materials is a monomeric glycoprotein with an apparent molecular weight of 45,700 t 500 contining 12% carbohydrate and an apparent isoelectric point of pH 5.9. It hydrolyzes tri-and di-phosphate of nucleosides as well as phosphate esters and exhibits characteristics of ATP-hydrolase and phosphatase. About 2-fold more of the APase was isolated from shriveled seeds, and the purified enzyme exhibited 3-and 5-fold higher V.. for p-nitrophenyl phosphate and ATP, respectively, than that of plump seed. The Ise for Pi concentration was 5.5-fold higher in APase of shriveled seed than the plump one. These varied quantitative and kinetic properties substantiate the role of APase in lines with shriveled seeds being reduction of starch accumulation by depleting substrates and energy supply in the cytosol.

Purification and Characterization of a Phosphoenolpyruvate Phosphatase from Brassica nigra Suspension Cells

“…The enzyme was found to be a monomer with a molecular mass of about 55 kD, which is similar to data reported for a soybean nonspecific acid phosphatase (53 kD monomer) (29) and soybean phytase (50 kD monomer) (11). This contrasts with findings reported for several nonspecific plant acid phosphatases which have a different subunit size and/or are multimeric (6,15,21), as well as cane leaf 3-PGA phosphatase (160 kD tetramer) (23) and tobacco leaf Pglycolate phosphatase (81 kD tetramer) (7). Unlike most other acid phosphatases, but similar to tobacco P-glycolate phosphatase (7), and soybean phytase (11), B. nigra PEP phosphatase required a divalent cation for optimal activity, was inhibited by EDTA, and was relatively heat-stable.…”

Purification and properties of acid phosphatase secreted from lupin roots under phosphorus-deficiency conditions

“…indicate that the native enzyme is a homo-dimer with a molecular weight of 72,000 for the subunit. This molecular weight of the homo-dimer was larger than that of other acid phosphatases purified from seeds of triticale (45,700 for monomer, Ching et al 1987), cell cultures of tomato (51,000 for dimer, Paul and Williamson 1987), barley roots (79,000 and 77,600 for dimer, Panara et al 1990), soybean axes and cotyledons (i00,000 for dimer, Kaneko et al 1990), seeds of sunflower (103,000 for dimer, Park and Etten 1986), tuberous root of sweet potato (110,000 and 105,000 for dimer, Uehara et al 1974), and cell culture of soybean (130,000 for dimer, LeBansky et al 1992), but smaller than that from cotton seedlings (200,000 for tetramer, Bhargava and Sachar 1987), and peanut seeds (240,000 for hexomer, Basha et al 1984). The isoelectric points (pI) of crude acid phosphatases from secretion, roots and leaves were determined by I E F (Fig.…”

“…The optimum pH was 4.3, which is ecologically significant because it indicates that the enzyme performs well in low pH soils where the availability of phosphate is mostly limited. As the optimum pH of acid phosphatase of the plants reported ranged from 4.5 to 6.0 (Basha 1984;Ching et al 1987;Angosto et al 1988;Kaneko et al 1990;Ullah and Gibson 1988;Tanaka et al 1990;Yoshimoto et al 1992), secreted acid phosphatase from lupin roots appeared to be adapted to much lower pH conditions.…”

“…It was suggested that acid phosphatases are glycoproteins (Felenbok 1970;Shinshi and Kato 1979;Park and Etten 1986;Ching et al 1987;Kaneko et al 1990;Tanaka et al 1990;Yoshimoto et al 1992). Based on the periodic acid-Schiff staining of the gel it was suggested that the acid phosphatase of lupin was also a glycoprotein (data not shown).…”

Differential Activity of Four Selected Enzymes in the Pistils and Pollen Grains of Two Varieties of Hamelia Patens Jacq. (Rubiaceae) Following Compatible and Incompatible Pollination.

“…The elevated levels of acid phosphatase in cross pollinated stigmaclearly indicate a role for this enzyme in pollen tube growth in the style. This enzyme is probably produced in response to the penetrating pollen tube for providing inorganic phosphates through hydrolysis of phosphate esters (Ching 1987). Activity of polyphenol oxidase is very low or negligible in stigmas after self-pollination and stigma before anthesis.…”