A homogeneous isoenzyme of human liver acid phosphatase

Saini, Mohan S.; Etten, Robert L. Van

doi:10.1016/0003-9861(78)90399-5

Cited by 68 publications

(27 citation statements)

References 40 publications

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“…Based on densitometer readings of APase stained gel, the activity ratio of 1:666:720 was observed for the three bands indicating the last two were active ones. It is known that minor charge heterogeneity of purified enzymes often occur and result in several bands after PAGE (7); HRIVELED SEEDS OF TRITICALE 793 (Table V) as other APase isolated from many organisms (1, 8,11,20,22,23,25). The relative activity in reference to pNPPase of the two materials toward different substrates was similar except GIP and NADP which were more favored by the enzyme isolated from the shriveled endosperm.…”

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confidence: 96%

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

Ching¹,

Tian²,

Metzger³

1987

Plant Physiol.

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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.

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confidence: 96%

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

Ching¹,

Tian²,

Metzger³

1987

Plant Physiol.

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“…This value is similar to molecular weight reported for prostatic acid phosphatases, 36,37) acid phosphatase of Drosophila virilis 38) and that of rat 39) and human liver. 8) These enzymes are all glycoproteins composed of identical or very similar subunits of molecular weights 50 kDa. The molecular weight of Zn ϩϩ -dependent acid p-nitrophenyl phosphatase was estimated to be 110 kDa on gel filtration.…”

Section: Resultsmentioning

confidence: 99%

“…HM-ACP was inhibited by fluorid and tartrate while LM-ACP isoenzymes were found to be insensitive to these known inhibitors as found in human liver enzymes. 8,9) Formaldehyde and p-hydroxymercuri-benzoates, a reagent of sulfhydryl groups, showed inhibitions to LM-ACP as observed in enzymes of human placenta 46) and bovin brain 47) but slight inhibition was exhibited by HM-ACP enzyme. Both molecular forms were deactivated by Cu ϩϩ and Hg ϩϩ .…”

Section: Fig 4 (A) Gel Chromatography On Sephadex G-100mentioning

confidence: 96%

“…[3][4][5][6] The effects of inhibitors, substrates and kinetic parameters also distinguish between the enzymes. [7][8][9] The acid phosphatase (molecular weight 107 kDa) purified from human liver to homogeneity had been extensively characterized. 5,8) The enzymes from liver of carp, catfish and frog had also been purified [10][11][12] and found to be glycoprotein in nature.…”

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confidence: 99%

“…[7][8][9] The acid phosphatase (molecular weight 107 kDa) purified from human liver to homogeneity had been extensively characterized. 5,8) The enzymes from liver of carp, catfish and frog had also been purified [10][11][12] and found to be glycoprotein in nature. Previously, low molecular weight acid phosphatases had been purified from human liver, 9,13) bovine liver, 3,14,15) rat liver, 16,17) porcine liver, 18) bovine heart, 19,20) brain, 21) human placenta 22) and human erythrocytes.…”

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confidence: 99%

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Acid Phosphatases from the Liver of Labeo rohita: Purification and Characterization

Siddiqua

Rehmat

Saeed

et al. 2008

Biological & Pharmaceutical Bulletin

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Acid phosphatases (EC 3.1.3.2) are widely distributed in nature and often occur in multiple forms differing in molecular sizes, localization within the cell, substrate specificity and sensitivity to inhibitors. 1) In animals its biological role is not yet clear but it is involved in many biological systems which are linked to energy metabolism, metabolic regulation and cellular signal transduction path ways. 2)Mammalian liver contains two acid phosphatase forms (molecular weight 90-107 kDa and 14-30 kDa) and these can be separated by gel chromatography on Sephadex G-75. [3][4][5][6] The effects of inhibitors, substrates and kinetic parameters also distinguish between the enzymes. 7-9) The acid phosphatase (molecular weight 107 kDa) purified from human liver to homogeneity had been extensively characterized. 5,8) The enzymes from liver of carp, catfish and frog had also been purified [10][11][12] and found to be glycoprotein in nature. Previously, low molecular weight acid phosphatases had been purified from human liver, 9,13) bovine liver, 3,14,15) rat liver, 16,17) porcine liver, 18) bovine heart, 19,20) brain, 21) human placenta 22) and human erythrocytes. 23) In all cases, the enzymes had molecular weights ranging between 14-18 kDa.Two distinct isoforms of low molecular weight acid phosphatase exist in rat liver (AcP1 and AcP2), human erythrocytes (B fast and B slow ) and human placenta (HCPTP-A and HCPTP-B) and these have also been isolated, characterized and sequenced. 17,24,25) The AcP1, B fast and HCPTP-A have been classified as IF-1 while AcP2, B slow , HCPTP-B, bovine heart PTPase and bovine liver PTPase as IF-2. IF-1 and IF-2 differ from each other in type specific sequence of the 40-73 regions, in substrate affinity and in the sensitivity to activators and inhibitors. 26) In our laboratory we have also purified and characterized these enzyme couples from chicken liver 27) and uromastix liver. 28) These differ in pyridoxal-5Ј-PO 4 inhibition, cGMP activation and some kinetic parameters. Both isoenzyme couples possess phosphotyrosine protein phosphatase activity. None of all enzymes (LM-ACP and HM-ACP) need metal ion for their activity.Another class of acid phosphatases called Zn ϩϩ -dependent acid phosphatases, exist in two forms of different molecular weight. 29,30) Zn ϩϩ -dependent acid phosphatases have also been isolated and characterized in the liver of different vertebrates. 31)This paper describes the purification and characterization of LM-ACP and HM-ACP from fish (Labeo rohita) liver and the resolution of the two low molecular weight isoenzymes (IF-1 and IF-2 types) by affinity chromatography on paminobenzyl phosphonic acid-agarose column. MATERIALS AND METHODSMaterials L. rohita (common name Rohu) was captured from Indus river (N.W.F.P. Pakistan) and liver was excised immediately and stored at 4°C for use. para-Nitrophenyl phosphate (pNPP), phenyl phosphate, flavin mononucleotide (FMN), phosphotyrosine and other substrates were purchased from Merk, Fluka and Sigma Chemical Co.; SDS molecular ...

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Abnormal acid phosphatases in neuronal ceroid‐lipofuscinoses

1995

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Acid phosphatases in brain and cultured lymphoblasts from patients affected with neuronal ceroid-lipofuscinoses (NCL) were studied by starch gel electrophoresis. After electrophoresis the gel was incubated with 4-methyl umbelliferyl phosphate at pH 4.5 and the fluorescent reaction product was visualized under ultraviolet light. Control brain showed a single band with mobility of about 1 cm while NCL patients showed two additional fast moving bands. In the late-infantile, and in the adult form (Kufs disease), the middle band was prominent while the fast moving band was predominant in juvenile NCL. In long-term lymphoblasts, controls showed a single band of acid phosphatase activity while both juvenile and late-infantile NCL showed two additional fast moving bands. Obligate heterozygotes showed reduced levels of the fast moving bands. Fluorometric assay of acid phosphatase using 4-methylumbelliferyl phosphate as substrate showed a 2-fold increase in activity in the patients. The increased acid phosphatase activity is completely inhibited by tartrate. Lymphocyte hexosamnidase activities were unchanged in NCL patients lymphoblasts. Studies on brains of NCL patients and on cultured lymphoblasts from families with late-infantile and juvenile form of NCL showed that abnormal acid phosphatase is characteristic of NCL.

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A homogeneous isoenzyme of human liver acid phosphatase

Cited by 68 publications

References 40 publications

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

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

Acid Phosphatases from the Liver of Labeo rohita: Purification and Characterization

Abnormal acid phosphatases in neuronal ceroid‐lipofuscinoses

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