Phosphatase acid

The isolation of the first manganese-containing acid phosphatase was reported in 1971 from the juice of the sweet potato (Kokei No. 14) (67). The enzyme was unique in that it was distinctly purple, the color resulting from a broad absorption band with a maximum at 555 nm. The enzyme was determined to be 110 kDa, composed of two 55-kDa subunits. The purple enzyme was capable of hydrolyzing a variety of biologically relevant phosphates as well as inorganic pyrophosphate [Eq. (2)]. Emission spectroscopy revealed the presence of Mn (68). 

Comparison of the visible spectrum with those of reported Mn SODs led 

The sweet potato enzyme could be inactivated by o-phenanthroline and 2,2 -bipyridine the activity could be restored by the addition of Zn2+ and partially by added Mn2+ or Co2+ (69). The amino acid composition revealed an usually large content of tyrosine. Later experiments were able to quantitate the amount of Mn present at two Mn per mole enzyme (70). Additionally, the native enzyme was shown to be EPR inactive however, treatment of the enzyme with acid led to the appearance of a six-line pattern typical of aqueous Mn2+ coincident with the loss of the purple color, further evidence for the association of Mn with the 555-nm absorbance band. 

Similar Mn-containing enzymes were subsequently isolated from other plant sources spinach leaves (71), rice plant cultured cells (72), soybeans (73-75), and the tubers of the sweet potato Kintoki (76-81) (Table III). Sweet potatoes have recently been reported to possess two different acid phosphatases which were immunologically distinct but which have similar molecular weights and metal content (106). Interestingly, sulfhydryl reagents have been shown to inactivate the soybean enzyme (75). 

Presently, the vast majority of information on the Mn site in these acid phosphatases comes from the enzyme from sweet potato tubers. This 110-kDa enzyme is identical to the previously reported sweet potato enzyme likewise, a 55-kDa subunit was found (78). However, the enzyme possesses only one Mn per enzyme molecule. At 293 and 77 K, no EPR signal could be detected for the native enzyme. Inactivation of the enzyme by heat treatment or the addition of acid results in the appearance of a six-line EPR pattern due to aquated Mn(II). As in the case of Mn SODs, this was taken as evidence for Mn(III) in the native 

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Acid phosphatase Acid phosphatases Acid pickling Acid rain... 

Hydrolysis 10 mmol of the phosphate salt are dissolved by swirling with Dowex AG50W-X8 (H ) in 200 mL of water. After filtration, the pH is adjusted to 6.0, acid phosphatase (150 U EC 3.1.3.2) is added and the mixture is incubated at 25 CC until complete conversion, as monitored by TLC (48 h). The solution is desalted by ion exchange, concentrated in vacuo, and the residue is crystallized from ethanol to give colorless crystals of D-sorbosc yield 1.6g (89%). 

Acid- and alkaline phosphatases act on a variety of mono- and multiple phosphate carrying low molecular mass molecules. In addition, they hydrolyze many, but not all, phosphoproteins. They are in use for decades to easily screen for diseases, however, somewhat unspe-cifially. For instance, acid phosphatase is used as biomarker for prostate cancer, and alkaline phosphatase to monitor bone (de-) mineralization and liver tumors. 

Dobias B (1984) Surfactant Adsorption on Minerals Related to Flotation. 56 91-147 Doi K, Antanaitis BC, Aisen P (1988) The Binuclear Iron Centres of Uteroferrin and the Purple Acid Phosphatases. 70 1-26 Domcke W, see Bradshaw AM (1975) 24 133-170 Dophin D, see Morgan B (1987) 64 115-204... 

A number of allergens from both honey bee and vespid venoms have been cloned and expressed by either Escherichia coli or baculovirus-infected insect cells (table 1) phospholipase Aj [20], hyaluronidase [21], acid phosphatase [13] and Api m6 [14] from honey bee venom, as well as antigen 5 [22], phospholipase A and hyaluronidase [23] from vespid venom, and dipeptidylpeptidases from both bee and Vespula venoms [15, 16]. Their reactivity with human-specific IgE antibodies to the respective allergens has been documented [11-16, 22, 23] and their specificity is superior... 

Grunwald T, Bockisch B, Spillner E, Ring J, Brede-horst R, Ollert M Molecular cloning and expression and expression in insect cells of honey bee venom allergen acid phosphatase (Api m3). J Allergy Clin Immunol 2006 117 848-854. 

His work on enzymes was continued during the Bonn period. Studies on acid phosphatases were carried out that made a major contribution to our knowledge of these enzymes. " The isolation of a crystalline /3-glucosidase from the emulsin of sweet almonds may be regarded as the crowning achievement of his work on glycosidases. ... 

Nadler, H. L. and Egan, T. J. "Deficiency of Lysosomal Acid Phosphatase a New Familial Metabolic Disorder". 

Sample Collection and Enzyme Stability. Serum samples are collected with chemically clean, sterile glassware. Blood is allowed to clot at room temperature, the clot is gently separated from the test tube with an applicator stick, and the blood is centrifuged for 10 minutes at 1,000 g. If the red cells are known to contain the enzymes whose activity is being measured, as in the case of LD, even slightly hemolyzed serums must be discarded. When acid phosphatase is to be measured, the serum should be placed immediately in ice and processed as soon as possible, or it should be acidified by the addition of a small amount of sodium citrate. Anticoagulants such as EDTA, fluoride and oxalate inhibit some serum enzymes. However, heparin activates serum lipoprotein lipase. 

Acid phosphatase catalyzes the dephosphorylation of an artificial organic substrate, such as B-glycerophosphate, phenyl-phosphate or thymolphthalein monophosphate. The analyst may measure either the phosphate or the organic radical liberated. 

The adult male prostate contains abundant acid phosphatase which it secretes into the semen. The production of this enzyme is governed by the circulating levels of androgenic hormones. Castration or estrogen administration markedly reduces the prostatic urinary acid phosphatase of males. Other organs such as the liver, kidney, spleen, red cells and platelets also contain significant amounts of acid phosphatase. 

Measurement of serum acid phosphatase activities as an aid in the diagnosis and treatment of advanced prostatic carcinoma is based on the observation by Gutman and Gutman that the activity is elevated by skeletal metastases ( ). Many workers have... 

Nodular hyperplasia of the prostate is usually associated with a normal serum acid phosphatase activity. Complications such as acute urinary obstruction or prostatic infarction will elevate this serum activity for several days as will cystoscopy and catheterization (98). Digital palpation of the prostate may result in an elevation which subsides within a few hours. 

The substrate phenyl phosphate, which is hydrolyzed by the serum acid phosphatases originating from many tissues, has been used in most of the published studies. Total serum acid phenylphos-phatase is elevated in diseases of the liver, disease of bone such as Paget s disease, and several blood dyscrasias, especially those involving platelets (99>100). 

Red blood cells also contain sufficient acid phenylphospha-tase for mild hemolysis to cause false elevations. Therefore, inhibitors such as ethanol, formaldehyde, copper sulfate> and 1-tartrate have been used to inhibit selectively the enzyme of one or more tissues and enhance the specificity of the test (101). Ethanol is unsuitable because it inhibits the enzyme from erythrocytes and prostate simultaneously, and because it yields serum activities which correlate poorly with prostatic disease. Formaldehyde inhibits the erythrocytic enzyme and has been said to yield clinically satisfactory results. The copoper resistant acid phosphatase of serum is elevated by metastatic carcinoma of the breast, as well as by other metastatic cancers, and is also elevated by a wide variety of non-cancerous diseases. 

Babson proposed a-naphthyl phosphate as an essentially specific substrate for the activity of prostatic acid phosphatase in serum (104). However Marshall, Price, and Amador found that this substrate is not specific for the prostatic enzyme because urine of human females contain 50 times more acid a-naphthyl phosphatase than male serum and 50% as much activity as male urine. Platelets have significant activity and the serum activity can increase to abnormal values following clotting. These workers also observed elevated activities in females with skeletal metastases of the breast. In 50 hospitalized male patients who had no evidence of prostatic cancer and 25 hospitalized female patients, the incidence of false positive results was 12%, a magnitude sufficient to preclude meaningful clinical interpretation (105). 

Gutman, A. B. and Gutman, . B. An "acid" phosphatase occurring in the serum of patients with metastasizing carcinoma of the prostate gland. J. Clin. Invest. (1938), 17, 473-478. 

Roy, A. V. Brown, M. E. and Hayden, J. E. Sodium thymolphthalein monophosphate, a new acid phosphatase substrate with greater specificity for the prostatic enzyme in serum. Clin. Chem. (1971), IJ, 1093-1102. 

Bonner, C. D. Hamburger, F. and Fishman, W. H. Some factors other than neoplasms altering the prostatic fraction of acid phosphatase in the serum. Surg. Gyn. 

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