Potato acid phosphatase

AGIRE computer program for, 249, 79-81, 225-226 comparison to analysis based on rates, 249, 61-63 complex reactions, 249, 75-78 experimental design, 249, 84-85 inhibitor effects, 249, 71-75 potato acid phosphatase product inhibition, 249, 73-74 preliminary fitting, 249, 82-84 prephenate dehydratase product inhibition, 249, 72-73 product inhibition effects, 249, 72-73 prostate acid phosphatase phenyl phosphate hydrolysis, 249, 70 reactions with two substrates, 249, 75-77 reversible reactions, 249, 77-78 with simple Michaelian enzyme, 249, 63-71 [fitting equations, 249, 63] with slow-binding inhibitors, 249, 88 with unstable enzymes, for kinetic characterization, 249, 85-89. 

Other - Farnesylpyrophosphate synthetase has been used in asymmetric synthesis of isoprenoids. Potato acid phosphatase has been applied to mild hydrolysis of polyprenyl pyrophosphates. Sulfatase-catalyzed hydrolysis of /9-napthol sulfate has been used to separate a- and 8-napthols. NAD and flavin adenine dinucleotide have been made by enzymic coupling reactions. 

Addition of substoichiometric amounts of either meiotic or mitotic lamin Drnmit to mixtures of interphase lamins Dmi and Dm2 apparently blocked aggregation/ polymerization of interphase isoforms (see Fig. 3). To affect in vitro behavior of lamins Dmi and Dm2, lamin Drnmit had to be added before aggregation/ polymerization of interphase isoforms. Treatment of lamin Drnmit with potato acid phosphatase to remove phosphate groups added in vivo abrogated the effect of lamin Drnmit on the behavior of lamins Dmi and Dm2. 

Enzyme electrode Orthophosphate 775 25 Biosensor based on glucose-6 -phosphate inhibition of hydrolysis by potato acid phosphatase, high selectivity for F [121]... 

Although reduction and activation are synonymous for the vast majority of the purple acid phosphatases, several exceptions exist. The Fe-Zn forms of uteroferrin and bovine spleen phosphatase do not require prior reduction to exhibit enzymatic activity . The Fe-Cu and Fe-Hg derivatives of uteroferrin also do not require activation and in fact, the Fe-Cu preparation is inactivated by reducing agents The recently described high molecular weight pink form of uteroferrin has enzymic properties identical to those of purple uteroferrin treated with 2-mercaptoethanoP. Finally, the sweet potato acid phosphatase, which may exist as an 02 dimer with separate mononuclear iron centers, does not require the addition of reductant to promote its enzymatic activity. ... 

Purple acid phosphatase (PAP) or tartrate-resistant phosphatase is not thought to be a protein phosphatase but it has a very similar dimetallic active site structure to that found in protein phosphatases. PAPs have been identified in bacteria, plants, mammals, and fungi. The molecular weights (animal 35 kDa, plant 55 kDa) are different and they exhibit low sequence homology between kingdoms but the residues involved in coordination of the metal ions are invariant. " There has been considerable debate as to the identity of the metal ions in PAPs in vivo. Sweet potato, Ipomoea batatas, has been shown to possess two different PAP enzymes and the active site of one of them has been shown to contain one Fe and one Zn " " ion. Another report has established that the active site of a PAP from sweet potato contains one Fe " and one Mn +. The well-characterized red kidney bean enzyme and the soybean enzyme contain Fe " and Zn. Claims that PAP from sweet potato has 2Fe ions or 2Mn ions have been discussed elsewhere. One explanation is that these are different forms of the enzyme, another is that because the metal ions are labile and are rapidly incorporated into the active site, the enzyme contains a mixture of metal ions in vivo and the form isolated depends on the conditions of isolation. 

Acid Phosphatase Potato CTAB/isooctane/chloroform Activity studies [97]... 

Some acid phosphatases from animals and plants are violet in color and contain iron (Chapter 16) and an Mn3+-containing acid phosphatase has been isolated from sweet potatoes.720 These enzymes have dimetal centers, often containing one Zn2+ and one Fe3+ with bridging carboxylate and hydroxide ions between the metals. Imidazole, tyrosinate, and carboxylate side chains hold the metals as in Fig. 16-20. A water molecule bound to the Fe3+ is thought to dissociate with a low pKa of 4.8 to give an Fe3+ OH complex. The hydroxyl ion can then attack the phospho groups, one... 

Purple, iron-containing acid phosphatases have been purified from animal sources and from some plant sources.350 However, the purple acid phosphatase from the sweet potato contains manganese, the purple colour arising from an intense absorption band at about 515 nm. There is some doubt over the stoichiometry, in that the dimeric enzyme may contain one351 or two352 Mn2+, apparently depending on the variety of sweet potato. The iron acid phosphatases contain two Fe atoms. 

A number of purple acid phosphatases821 have been isolated from animal sources, including bovine spleen, rat bone and the enamel organ of rat molars. Other phosphatases may belong to this class but the identification is not yet certain. Purple acid phosphatase from the sweet potato, as noted in Section 62.1.3.6.1, contains manganese. 

Acid phosphatase (EC 3.1.3-2) Sigma type III from potato at... 

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). 

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... 

So far, only very little attention has been focussed on the use of zeolites in biocatalysis, i.e., as supports for the immobilization of enzymes. Lie and Molin [116] studied the influence of hydrophobicity (dealuminated mordenite) and hydrophilicity (zeolite NaY) of the support on the adsorption of lipase from Candida cylindracea. The adsorption was achieved by precipitation of the enzyme with acetone. Hydrolysis of triacylglycerols and esterification of fatty acids with glycerol were the reactions studied. It was observed that the nature of the zeolite support has a significant influence on enzyme catalysis. Hydrolysis was blocked on the hydrophobic mordenite, but the esterification reaction was mediated. This reaction was, on the other hand, almost completely suppressed on the hydrophilic faujasite. The adsorption of enzymes on supports was also intensively examined with alkaline phosphatase on bentolite-L clay. The pH of the solution turned out to be very important both for the immobilization and for the activity of the enzyme [117]. Acid phosphatase from potato was immobilized onto zeolite NaX [118]. Also in this study, adsorption conditions were important in causing even multilayer formation of the enzyme on the zeolite. The influence of the cations in the zeolite support was scrutinized as well, and zeolite NaX turned out to be a better adsorbent than LiX orKX. 

Feng, J., Yuan, F., Gao, Y, Liang, C., Xu, )., Zhang, C., He, L. A novel antimicrobial protein isolated from potato [Solanum tuberosum) shares homology with an acid phosphatase. Biochem. J. 2003, 376, 481-487... 

The purple acid phosphatases (PAP) catalyze the hydrolysis of phosphate esters under acidic pH conditions (pH optimum 5) (9, 10). They differ from other acid phosphatases in having a distinct purple color due to the presence of iron or manganese and in being uninhibited by tartrate. Diiron units have been found in the active sites of the enzymes from mammalian spleen (171-173) and uterus (173, 174), while a heterodinu-clear FeZn unit has been characterized for the enzyme from red kidney bean (175). Either the Fe2 or the FeZn unit is catalytically competent in these enzymes, since the enzymes from porcine uterus and bovine spleen can be converted into active FeZn forms and the kidney bean enzyme can be transformed into an active Fe2 form (176). There are also enzymes from other plant sources (particularly sweet potato) that have been reported to have either a mononuclear Mn(III) or Fe(III) active site (177), but these are beyond the scope of the review. This section will focus on the enzymes from porcine uterus (also called uteroferrin), bovine spleen, and red kidney bean. 

A number of acid and alkaline phosphatases and specific phytases are activated by divalent metal ions. After its inactivation by o-phenanthrolin and a,a -dipyridil at 50°C, the manganese-containing acid phosphatase from sweet potato was reactivated by the addition of metal ions (Uehara et ah, 1974). The EDTA-inhibited alkaline phosphatase of Lysobacter enzymogenes was reactivated by divalent metal ions at 0.05 mM (von Tigerstrom and Stelmaschuk, 1986) specifically, reactivation was caused by magnesium chloride (4.6%), calcium chloride (7%), manganese chloride (14.5%), cobalt chloride (24%) and zinc chloride (66%). 

Uehara, K., Fujimoto, S., Taniguchi, T. and Nakai, K. (1974) Studies on violet-colored acid phosphatase of sweet potato. II. Enzymatic properties and amino acid composition. Journal of Biochemistry 75, 539-649. 

Purple Acid Phosphatases. Purple acid phosphatases (PAPs) utilize a dinuclear metal center to catalyze the hydrolysis of phosphate monoesters. The characteristic purple color of these enzymes arises from a charge transfer absorption at about 560 nm, between a tyrosinate ligand and the conserved Fe + found in all PAPs. The second metal ion varies with the source of the enzyme and is always divalent. Mammalian PAPs are monomeric and have Fe -Fe " centers, whereas most plant PAPs are dimeric with Fe " -Zn + centers. A PAP isolated from sweet potato contains an Fe +-Mn + center, the first of its kind in any enzyme (26,27). This novel PAP also differs from others by its greater catalytic efficiency toward both activated and unactivated substrates (27), as well as in its strict requirement for manganese in the divalent site (26). 

Lipase and alkaline phosphatase in milk are ther-molabile (Fig. 2.37), whereas acid phosphatase is relatively stable. Therefore, alkaline phosphatase is used to distinguish raw from pasteurized milk because its activity is easier to determine than that of lipase. Of all the enzymes in the potato tuber (Fig. 2.38), peroxidase is the last one to be thermally inactivated. Such inactivation patterns are often found among enzymes in vegetables. In such cases, peroxidase is a suitable indicator for controlling the total inactivation of all the enzymes e. g., in assessing the adequacy of a blanching process. However, newer developments aim to limit the enzyme inactivation to... 

Schenk G, Gahan LR, Carrington LE, Mitic N, Valizadeh M, Hanfilton SE, de Jersey J, Guddat LW. 2005. Phosphate forms an unusual liipodal complex with the Fe-Mn center of sweet potato purple acid phosphatase. Proc Natl Acad Sci USA 102 273-278. 

Schenk G, Ge YB, Carrington LE, Wynne CJ, Searle IR, CarroU BJ, Hamilton S, de Jersey J. 1999. Binuclear metal centers in plant purple acid phosphatases Fe-Mn in sweet potato and Fe-Zn in soybean. Arch Biochem Biophys 370 183-189. 

Schenk G, Boutchard CL, Carrington LE, Noble CJ, Moubaraki B, Murray KS, de Jersey J, Hanson GR, Hamilton S. 2001. A purple acid phosphatase fi"om sweet potato contains an antiferromagnetically coupled binuclear Fe-Mn center. J Biol Chem 276 19084-19088. 

In addition to its archetypical members, uteroferrin and bovine spleen add phosphatase, the class of purple add phosphatases includes proteins isolated from rat bone and. spleen spleens of patients with Gaucher s disease or leukemic reticuloen-dotheliosis equine uterine flushings bovine cortical bone giant ceU tumors human placenta and microorganisms . The plant enzymes include an Fe-Zn phosphatase from red kidney beans and an Fe-Fe or Mn(in) protein from sweet potato tubers . Although less well-defined and more heterogeneous than their mammalian counterparts, the color and iron content of the plant enzymes warrant their designation as purple acid phosphatases. 

In a final experiment we investigated the possible occurence of other common (nonlipolytic) hydrolases in the patatin fraction from potato tubers. High levels of acid phosphatase and N-acetyl glucosamini-dase activities were detected (data not shown). The occurence of at least 3 different enzyme activities in the patatin fraction causes one to question whether the 6-10 isoforms (ionic forms) which comprise the patatin fraction actually have very much in common (4). 

Example of multistep chemo-enzymatic synthesis of pipecolic acid derivatives (60) and homoiminocyclitols (61) by two consecutive enzymatic aldol addition reactions (a) i-serine hydroxy-methyltransferase from Streptococcus thermophilus (lSHMTj ) (b) Cbz-OSu CHjCN/aqueous HCI (c) Cbz-OSu MeOH/SO CIj CaCI, NaBH, EtOH/THF CHjCN/aqueous HCI (d) o-threonine aldolase from Achromobacterxylosoxidans (oThrA j (e) FucA F131A (f) RhuA wild-type (g) acid phosphatase from potato type II and (h) H Pd/C. 

An acid phosphatase (AP) hybrid biosensor was developed using a thin layer of potato tissue coupled to an amperometric GOD-based biosensor based on internal sensing of H202. The reversible inhibition of AP was utilized for the determination of malathion, paraoxon methyl, paraoxon, and aldicarb with limits of detection of 0.5 ppb for paraoxon methyl, and 40 ppb for aldicarb. The tissue-based biosensor exhibited a longer shelf life and abetter reliability on the amperometric results than a bi-enzymatic sensor with purified AP and GOD. A similar biosensor was also developed using a potato layer with a Clark-type dissolved oxygen electrode. ... 

The amino acid compositions of the beta-amylase from sweet potato, soya bean, wheat, and malted sorghum have been determined, and are shown in Table XIII. These results may suggest that the beta-amylase from these different sources differs in structure. This is, perhaps, not surprising, but it should be noted that the sorghum amylase contained 9% of pentose, and the important, sulfiir-containing amino acid cysteine was not reported and the soya-bean enzyme still contained traces of aipba-amylase and phosphatase. The sequence of amino acids, or the three-dimensional structure of any... 

Most amylase preparations have a certain phosphatase activity. Some of the preparations used in our experiments were tested on glycerophosphate (Table XXVI) at pH 5.3 and 30°. Parallel experiments with potato starch (Table XXVI) show that the action of the phosphatases on the combined phosphoric acid in starch or limit dextrins, respectively, is very slight compared to the action on glycerophosphate. It is not clear... 

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