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Showing papers on "Esterase published in 1968"


Journal ArticleDOI
TL;DR: Physiological cell death and degeneration in the interdigital mesenchyme of the hind foot of the rat foetus have been studied and no evidence was found suggesting that cell death might be initiated by the intracellular release of lysosomal enzymes.
Abstract: Physiological cell death and degeneration in the interdigital mesenchyme of the hind foot of the rat foetus have been studied using classical staining methods and staining methods for enzyme localization. Individual mesenchymal cells die and shrink as the result of some unknown mechanism. Their acid phosphatase and esterase activities are not significantly different from those of viable loose mesenchymal cells. The dead cells are engulfed by viable neighbouring cells which resemble other loose mesenchymal cells in their morphology and in their acid phosphatase and esterase activities. These phagocytes then differentiate and become typical macrophages. Expressions of this process are the altered appearance of their nuclei and the increase in cytoplasm and in acid phosphatase and esterase activities. Many dead cells may be engulfed by a single macrophage and are then digested by its acid hydrolases. No evidence was found suggesting that cell death might be initiated by the intracellular release of lysosomal enzymes.

126 citations


Journal ArticleDOI
TL;DR: While the mechanism of the effect of activated Hageman factor upon C'1 activation remains obscure, it is apparent that some intermediate steps, possibly involving a kinin-forming system of plasma, may play a role.
Abstract: The generation of C'1 esterase activity in siliconed plasma obtained from individuals with hereditary angioneurotic edema in remission tends to occur spontaneously, but can be hastened during its incubation with preparations of activated Hageman factor. This effect of activated Hageman factor could not be shown during its incubation with normal siliconed plasma, nor could consumption of normal serum inhibition of C'1 esterase be clearly shown. Soy bean trypsin inhibitor and heparin could impair this enhanced generation of C'1 esterase but neither inhibits the esterolytic function of C'1 esterase once formed. Trasylol was less effective in blocking this effect of activated Hageman factor. While the mechanism of the effect of activated Hageman factor upon C'1 activation remains obscure, it is apparent that some intermediate steps, possibly involving a kinin-forming system of plasma, may play a role.

126 citations


Journal ArticleDOI
TL;DR: Immunochemical analysis using a variety of specific antisera, including a monospecific antiserum to the isolated protein, indicate that the C'2 protein represents a heretofore unrecognized human serum constituent.
Abstract: A method has been described for the purification and isolation of the second component of complement (C'2) from human serum. The protein is a β1-globulin with an approximate molecular weight of 117,000. Immunochemical analysis using a variety of specific antisera, including a monospecific antiserum to the isolated protein, indicate that the C'2 protein represents a heretofore unrecognized human serum constituent. Isolated C'2 contained 2 x 109 "effective molecules" per microgram and 1000 hemolytically active C'2 molecules were required to produce a single hemolytically effective C'2 site on erythrocytes undergoing immune cytolysis. C'1 esterase treatment of C'2 resulted in reduction of both its electrophoretic mobility and its molecular size, the latter observation indicating fragmentation of the molecule. Direct evidence was presented for the physical presence of C'2 as an integral part of the enzyme C'3 convertase.

111 citations


Journal ArticleDOI
TL;DR: Dipeptidyl arylamidase II of the anterior pituitary gland has been extensively purified by means of (NH4)2SO4 fractionation, isoelectric precipitation, chromatography on diethylaminoethyl cellulose and IRC-50, and gel filtration on Sephadex G-200.

109 citations


Journal ArticleDOI
TL;DR: Human C'1, a macromolecular complex composed of three subunits, is the zymogen for at least two distinct enzymes and evidence was presented which indicates that these three functions are properties of a single entity, C' 1r, but not of the same portion of its molecular structure.
Abstract: Human C'1, a macromolecular complex composed of three subunits, is the zymogen for at least two distinct enzymes. Preparations of one subunit, C'1r, functioned as a protease which converted another subunit, C'1s, to C'1 esterase. The conversion of C'1s to C'1 esterase by C'1r was blocked by Liquoid, phenyl methylsulfonyl fluoride, and calcium ions, but not by soybean trypsin inhibitor, hirudin, or heparin. Preparations of C'1r also possessed two additional functions, i.e., the ability to hydrolyze certain synthetic amino acid esters and to participate in immune hemolysis. Evidence was presented which indicates that these three functions are properties of a single entity, C'1r, but not of the same portion of its molecular structure. These observations suggest that C'1r has at least two active sites, one for its reaction with C'1q, an additional subunit of C'1, and one for its reaction with C'1s; together, the three subcomponents, C'1q, C'1r, and C'1s, form a single functional unit, the first component of complement.

104 citations


Journal ArticleDOI
TL;DR: A developmental study of esterase isoenzyme patterns indicated that no great differences exist between primary root tips from roots 6-18 mm long and seeds germinated for three days, whereas a sudden decrease in enzymatic activity occurs in root tips after seven days' germination when the roots were about 25 mm long as mentioned in this paper.
Abstract: A total of 21 esterase, 3 acid phosphatase and 2 leucinc aminopeptidase isoenzymes, in addition to peroxidases and catalases, were demonstrated in onion seedlings by starch-gel electrophoresis. In seedlings two weeks old, the root tip and the differentiated zone show very little enzymatic activity, whereas the secondary roots, hypo-cotyl and cotyledon are enzymatically very active. These differences are correlated with the intensity of cell division. Some esterase isoenzymes are apparently restricted to root, others to shoot tissues. At pH 8.1, anodically moving peroxidases are totally absent from shoot tissues. A developmental study of esterase isoenzyme patterns indicated that no great differences exist between primary root tips from roots 6–18 mm long and seeds germinated for three days, whereas a sudden decrease in enzymatic activity occurs in root tips after seven days' germination when the roots are about 25 mm long. This coincides with the decrease in mitotic Frequency. Actinomycin D and gamma irradiation decreased mitotic frequency almost to zero but did not significantly affect the esterase isoenzyme pattern in root tips. This shows that the activity of these isoenzymes, at least, is not necessarily dependent on cell division but may well be a prerequisite for it.

89 citations


Journal ArticleDOI
TL;DR: Esterase activity was investigated in blood cells of peripheral blood and bone marrow in healthy subjects and in various pathological conditions, using α‐naphthyl acetate, naphthol AS‐D acetate and naphtha chloroacetate as substrates.
Abstract: Summary. Esterase activity was investigated in blood cells of peripheral blood and bone marrow in healthy subjects and in various pathological conditions. As substrates were used: α-naphthyl acetate, naphthol AS-D acetate and naphthol AS-D chloroacetate. Fast blue B and fast garnet G. B. C. were used as coupling agents. The distribution of AS-D acetate esterase in different blood cells was described. Strong α-naphthyl acetate esterase activity was found in monocytes, reticulum cells, megakaryocytes and in monoblasts in cases of monocytic leukaemia. Weak activity was shown in thrombocytes, and in lymphocytes. With naphthol AS-D chloroacetate as substrate strong enzymatic activity was demonstrated in the cells of the neutrophilic myelocytic series. The activity was strong in the more mature cells. Blasts from acute myelocytic leukaemia showed enzymatic activity. The use of α-naphthyl acetate and naphthol AS-D chloroacetate as substrates proved to be of help in differentiating between the three types of acute leukaemia. In cases with megaloblastic erythropoiesis only strong α-naphthyl acetate esterase activity was demonstrated in the megaloblasts. Successful treatment of pernicious anaemia with B12, resulted in disappearance of megaloblasts and cessation of the strong esterase activity. There seems to be a correlation between strong naphthyl acetate esterase activity and the presence of megaloblasts. An explanation of this phenomenon is suggested.

82 citations


Journal ArticleDOI
TL;DR: The apparently normal response to intradermal C'1 esterase developed by individuals with an acquired specific deficiency of C'3 suggests that the vasoactive substance may be derived from one of the early reacting complement components.
Abstract: When purified human C′1 esterase is injected intradermally in man, increased vascular permeability results. This effect is not blocked by soybean trypsin inhibitor and is not abolished by pretreatment with the antihistamine, pyribenzamine, or by compound 48/80. Thus, the effect is not due to the release of endogenous histamine. The decreased permeability response of individuals with a specific hereditary deficiency of C′2 is evidence for the complement-dependent nature of this reaction. The apparently normal response to intradermal C′1 esterase developed by individuals with an acquired specific deficiency of C′3 suggests that the vasoactive substance may be derived from one of the early reacting complement components. Characteristic attacks of angioedema have been provoked by the intradermal injection of human C′1 esterase in two individuals with hereditary angioneurotic edema. Patients with hereditary angioneurotic edema are unresponsive to intradermal injections of C′1 esterase immediately after attacks.

74 citations


Journal ArticleDOI
TL;DR: A series of ester substrates are designed and synthesized which provide both a cytochemical indicator of the location of the enzyme and a means of following the enzymatic activity in tissue homogenates and subfractions to correlate the intracellular site of action and the biochemical behavior of the esterases.
Abstract: The esterases of rabbit lung have been investigated from two viewpoints, the cytochemical and the biochemical. To accomplish this objective, we designed and synthesized a series of ester substrates which provide both a cytochemical indicator of the location of the enzyme and a means of following the enzymatic activity in tissue homogenates and subfractions. The substrates are p-nitrophenylthiol esters which yield, upon hydrolysis, carboxylic acid and p-nitrothiophenol. The latter can react with aurous ions to give an electron-opaque deposit; in addition, the strong absorption of p-nitrothiophenol at 410 mµ permits continuous kinetic measurements. Thus, it is possible to correlate the intracellular site of action and the biochemical behavior of the esterases. The new substrates are the thiol analogues of the p-nitrophenyl esters frequently employed as esterase substrates. The rates of hydrolysis of the two series of esters are compared in vitro. During tissue fractionation, most of the esterase activity sediments with a particulate fraction. The effects of a number of common esterase inhibitors, such as diisopropyl phosphorofluoridate and eserine sulfate, are examined, and the effects of enzyme concentration and heat inactivation are shown with the use of the partially purified preparations. The cytochemical work shows that the esterase activity is most prominent in the lamellar bodies of the giant alveolar (type II, septal, or granular pneumatocyte) cells of the lung and to a lesser extent in squamous (type I, or membranous pneumatocyte) epithelial and endothelial cells. In both the cytochemical and biochemical studies, the enzymes are inhibited by diisopropyl phosphorofluoridate and phenyl methylsulfonyl fluoride but are insensitive to eserine sulfate.

73 citations


Journal ArticleDOI
TL;DR: By comparing esterase zymograms from different tissues and from different species, it is apparent that the distribution and multiplicity of ester enzyme activity is tissue and species specific.

70 citations


Journal Article
TL;DR: A patient with clinical and laboratory findings characteristic of hereditary angioneurotic oedema was investigated and e-Aminocaproic acid (EACA) was given continuously for 5 months, during which time the patient had no attacks.
Abstract: A patient with clinical and laboratory findings characteristic of hereditary angioneurotic oedema was investigated. The patient was observed for a period of 5 weeks, during which he had four attacks. e-Aminocaproic acid (EACA) was then given continuously for 5 months, during which time the patient had no attacks. Attacks reappeared on withdrawal of EACA. Trans-4-(aminomethyl) cyclohexane carboxylic acid (AMCA®) was found to be equally effective in later therapeutic trials. C'1 esterase inhibitor was found in low concentration in defibrinated plasma also during attacks. e-Aminocaproic acid (EACA) produced no significant change of the inhibitor content. C'1 esterase inhibitor disappeared on incubation of defibrinated plasma from the patient at 37°C for 40 min, and C'1 esterase was generated. The generation time of C'1 esterase increased with increasing the concentration of EDTA in the test solution. The C'1 esterase inhibitor content of defibrinated plasma from the patient, varied with the C'1 esterase generation time, the coefficient of correlation being higher in plasma sampled before treatment with EACA. Plasminogen and α2-macroglobulin were within the normal ranges, also during attacks. EACA markedly depressed the plasminogen level, which rapidly returned to normal on withdrawal of the drug. The studies on histamine metabolism revealed no significant changes with the exception of the urinary excretion of histamine, which was moderately increased towards the end of the period studied. On the days the patient received EACA the urine never contained 1-methylimidazole-5-acetic acid which was present in all the other specimens of urine examined. The basal gastric acid secretion was increased.

Journal ArticleDOI
01 Jan 1968-Analyst
TL;DR: An enzymatic inhibition method sufficiently sensitive and reproducible for detecting ten organophosphorus pesticides and carbaryl resolved by thin-layer chromatography is described, with results satisfactory with 1-naphthyl acetate as substrate, and with bovine and sheep sera as sources of esterase.
Abstract: An enzymatic inhibition method sufficiently sensitive and reproducible for detecting ten organophosphorus pesticides and carbaryl resolved by thin-layer chromatography is described. Reproducible detection of nanogram amounts of these pesticides is achieved with a 450-µ thick gel layer, steer-liver homogenate as source of esterase, and indoxyl or substituted indoxyl acetates (5-bromoindoxyl, 5-bromo-4-chloroindoxyl and 5-bromo-6-chloroindoxyl acetates) as substrates, the esterase and substrate spray solutions being used at a pH of about 8. The coloured products of enzymatic hydrolysis of these substrates are stable and intense; white spots indicated the sites of pesticides that inhibited the enzyme.Spots persist for days when the amounts present are 1 ng of parathion; 2ng of carbophenothion; 5ng of azinphos-methyl, diazinon, ethion, malathion and parathion-methyl; 20 ng of carbaryl, Trithion®-methyl and mevinphos; and 100ng of disulfoton. Carbophenothion and disulfoton are also detected at the 1 ng level and carbaryl, at 5 ng; however, the spots produced disappear within a few hours.Unsatisfactory results are obtained with 1-naphthyl acetate as substrate, and with bovine and sheep sera as sources of esterase.

Journal ArticleDOI
TL;DR: It is concluded that the high lipase and low cholesterol esterase activity in the peanut oil fed rat, and the low cholesterol EsteraseActivity in the semi-synthetic diet fed rabbit may be contributing factors in the dietary production of atherosclerosis in these two species.

Journal ArticleDOI
TL;DR: The cell extract studies demonstrated that the cells contained intracellular esterases and lipases, and it was suggested that the lipase of these organisms is an endoenzyme and the esterase an ectoenzyme.
Abstract: Seventeen strains of lactic acid bacteria were assayed for their glycerol ester hydrolase activity by using an improved agar-well technique, and eight strains by determining the activity in cell-free extracts using a pH-stat procedure. All cultures tested showed activity and hydrolyzed tributyrin more actively than they did tricaproin. The cell extract studies demonstrated that the cells contained intracellular esterases and lipases. The culture supernatant fluid was without activity. The lipase and the esterase differed in their relative activity to each other in the different extracts and in the ease by which they could be freed from the cellular debris. It is suggested that the lipase of these organisms is an endoenzyme and the esterase an ectoenzyme.

Journal ArticleDOI
TL;DR: Forty-five potato varieties were analysed for three biochemical systems obtained from tuber extracts, finding this is an effective and efficient procedure for variety identification.
Abstract: Forty-five potato varieties were analysed for three biochemical systems obtained from tuber extracts. The systems employed were esterase and peroxidase isozymes and soluble-proteins patterns; separation was accomplished by disc electrophoresis. Five esterase isozymes, a group of eight peroxidase isozymes and more than 20 proteins were present in unique combinations specific for each variety. This is an effective and efficient procedure for variety identification.

Journal ArticleDOI
TL;DR: In this paper, the authors showed that hepatic triglyceride lipase resembles esterase since it hydrolyzes the water-soluble substrate better than the waterinsoluble substrate.
Abstract: There are at least two sites on the lipase which are concerned with catalysis: the catalytic site and the hydrophobic recognition site (lipid-binding site). The recognition site may be destroyed by mild proteolytic digestion, but the catalytic site may not be changed by this treatment. Mild treatment with trypsin caused change in the catalytic properties of hepatic triglyceride lipase; the water-insoluble ester-hydrolyzing activity of hepatic triglyceride lipase decreased, whereas the water-soluble ester-hydrolyzing activity did not change. After proteolytic digestion, hepatic triglyceride lipase resembles esterase since it hydrolyzes the water-soluble substrate better than the water-insoluble substrate. Conversely, esterase was converted to lipase by treatment with phospholipid. Cardiolipin in a concentration-dependent fashion enhanced triolein-hydrolysis of human serum carboxylesterase and this effect was associated with a dose-dependent decrease in water-soluble tributyrin hydrolysis. Based on these results, we propose the hypothesis that lipase and esterase have similar catalytic sites and that addition of a hydrophobic recognition site to esterase causes conversion of esterase to lipase (Fig. 9).

Journal ArticleDOI
TL;DR: On the basis of the various types of proteolytic specificity found for the protease a new concept is put forward for understanding collagen breakdown in vivo and in vitro.
Abstract: 1 A highly purified protease has been prepared from culture filtrates of Aspergillus oryzae. The process consists of four steps, namely the dialysis of the starting material, precipitation with acetone, separation by carrier-free electrophoresis and fractionation with acetone. The specific activity of the protease is increased 40 times or more. The product was shown to be a single substance by means of the ultracentrifuge, disc electrophoresis and immuno-electrophoresis. As far as investigated, it is free of non-specific activities. 2 The molecular weight was found to be about 20,000 by elution from a Sephadex G-75 column, by ultracentrifugation and by amino acid analysis. The pH optimum normally lies between 9 and 10. The protease cannot be activated with metal ions; it is, however, inhibited by Cu2+, Hg2+ and Zn2+ ions. It is also inhibited by di-isopropyl phosphofluoridate and other compounds that react specifically with serine. 3 The protease splits denatured proteins preferentially, but not solely, at the peptide bonds of amino acids with acid side chains as shown by investigations on long-chain model peptides. It also digests native collagen. The mode of splitting is the same as that by which the collagenase from Clostridium histolyticum splits the apolar regions. However, bonds involving hydroxyproline appear to be resistant to attack by the Aspergillus enzyme. In addition, the protease described here is capable of digesting bonds of the polar regions of the native collagen molecule. The protease also acts as an esterase. 4 On the basis of the various types of proteolytic specificity found for the protease a new concept is put forward for understanding collagen breakdown in vivo and in vitro.

Journal ArticleDOI
TL;DR: Four main classes of esterase activity have been characterized (carboxyl-esterases, arylesterases, acetylesterase and cholinesterases), but evidence for further differentiation of activity-types within these groups is also presented.


Journal ArticleDOI
TL;DR: Esterase zymograms were prepared from 14 species and strains of Culicide mosquitoes by use of starch and polyacrylamide electrophoresis and it was shown that certain isozymes apparently are activated by inhibitors.
Abstract: Esterase zymograms were prepared from 14 species and strains of Culicide mosquitoes by use of starch and polyacrylamide electrophoresis. The zymograms proved to be species- and strain-specific. Var...

Journal ArticleDOI
TL;DR: In this paper, a commercial preparation of Streptomyces griseus protease (Pronase, Calbiochem) has been shown to contain at least three DFP-reacting components.

Journal ArticleDOI
TL;DR: Evidence was given to show that the intensity of this interaction in circulating plasma increased gradually with time, with the concordance of this in vivo inter-action with the in vitro degradation and inactivation of endotoxin by plasma esterases discussed.
Abstract: Circulating endotoxin was specifically precipitated from plasma samples withdrawn from three different animal species subsequent to parenteral injection of the toxin. Lipoprotein-positive staining and esterase activity were demonstrated on the precipitation lines formed in immunodiffusion, thus establishing the in vivo interaction of endotoxin with a plasma lipoprotein having esterase activity. Evidence was given to show that the intensity of this interaction in circulating plasma increased gradually with time. The concordance of this in vivo inter-action with the in vitro degradation and inactivation of endotoxin by plasma esterases is discussed. Images

Journal ArticleDOI
TL;DR: Electrophoresis patterns of soluble protein of 34 strains and esterases of 113 strains of lactic acid bacteria were determined and most species gave constant species-specific patterns, but Lactobacilli acidophilus and L. delbrueckii strains differed markedly among themselves.
Abstract: SUMMARY: Electrophoresis patterns of soluble protein of 34 strains and esterases of 113 strains of lactic acid bacteria were determined. Similar protein patterns were obtained for the three species of lactic acid streptococci; with the lactobacilli most species gave constant species-specific patterns, but Lactobacillus acidophilus and L. delbrueckii strains differed markedly among themselves. Esterase patterns of lactic streptococci were generally species specific. Among the lactobacilli the thermobacteria had weak esterase activity which was only species specific for L. lactis, L. leichmanii and L. salivarius; in the streptobacteria, L. casei had a very consistent esterase pattern, whereas L. plantarum had very different patterns within the species; the unclassified strains were different from each other; in the betabacteria activity was weak and no consistent pattern of bands occurred. Leuconostocs grouped in patterns corresponding to their physiological groups. Esterases of a streptococcus and a lactobacillus examined were classified as ali esterases. When ten strains of lactic acid bacteria were tested for substrate specificity, nine of them had a higher activity against α-naphthyl acetate than against the butyrate and caprylate. A rapid test for esterase activity of whole organisms is described.

Journal ArticleDOI
TL;DR: Esterases, acting on higher fatty acid esters of p-nitrophenol, are shown to be concentrated in the lysosomes of rat liver and kidney by the amount of enzyme sedimented with light mitochondria, by the purification of lYSosomes, and by the preparation of Triton WR 1339-filled liver lysOSomes.

Journal ArticleDOI
TL;DR: Disintegration of lyophilized Bacteroides amylophilus H 18 suspended in water, by agitation with glass beads, gave an extract containing 40% of the total cell protease activity, indicating a trypsin-like specificity.
Abstract: SUMMARY: Disintegration of lyophilized Bacteroides amylophilus H 18 suspended in water, by agitation with glass beads, gave an extract containing 40% of the total cell protease activity. Better yields of an esterase which hydrolysed p-toluenesulphonyl-L-arginine methyl ester (TAME) were obtained by disintegration in 0.1 M-phosphate buffer (pH 7.0). Ultrasonic disintegration of fresh suspensions was used to obtain larger quantities of cell extract. The protease had a broad plateau of activity between pH 5.5 and 9.5; the esterase had maximum activity at pH 8.0. Divalent cations had relatively little effect on either activity but 5 x 10-3 M-CaCl2 restored activity to EDTA-inhibited esterase. The protease was not inhibited by EDTA. Both activities were inhibited by di-isopropylphosphofluoridate but the protease was incompletely inhibited (87%). Neither activity was activated nor inhibited by thiol reagents. In addition to TAME, N-α-benzoyl-L-arginine methyl ester (BAME), N-α-benzoyl-L-arginine ethyl ester (BAEE), N-α-benzoyl-DL-arginine-p-nitroanilide and lysine ethyl ester were hydrolysed, indicating a trypsin-like specificity. The esterase differed from trypsin in not hydrolysing N-α-benzoyl-L-arginine amide (BAA) nor N-α-benzoyl-DL-arginine-naphthylamide (BANA) and in hydrolysing BAME more rapidly than TAME. There was some hydrolysis of N-α-benzoyl-L-leucyl-2-naphthylamide and some amino peptidase activity as shown by the hydrolysis of L-analyl-2-naphthylamide, L-leucylglycine and L-leucinamide. TAME competitively inhibited at least 64% of the protease activity. The K m for casein was 0.17% (w/v). Casein at concentrations greater than 3.0% (w/v) caused substrate inhibition. The rate of ‘tyrosine’ liberation was proportional to protease concentration provided that less than 0.5 mg. ‘tyrosine’ was liberated from the 80 mg. casein in the standard assay. Protease concentration to the power 2/3 or the power 1/2 was proportional to the rate of hydrolysis but the straight line did not go to the origin. Bacteroides amylophilus H 18 extracts contained much nucleic acid which could not be separated from the protease activity by ammonium sulphate, protamine sulphate nor manganese chloride precipitation. Continuous electrophoresis was also ineffective. Ion-exchange chromatography separated the nucleic acids, but the protease activity was scattered in so many fractions that the purification was only three-fold and the recoveries poor.

Journal ArticleDOI
TL;DR: Previous reports concerning these phenomena of N-substituted products of hydrolysis of certain synthetic peptide and ester substrates are extended and relates them to the kinetic data currently available on carboxypeptidase catalysis.

Journal ArticleDOI
TL;DR: In both adult and developing brain, zymograms of bound esterase resembled those of the free enzyme, the major difference being the presence in the former of a slow, broad, anodic zone of diethyl‐p‐nitrophenyl phosphate‐inhibited enzyme.
Abstract: The free and bound nonspecific esterases occurring in, respectively, the saline and triton X-100 extracts of adult and developing human brain were studied by starch gel electrophoresis (zymograms). Zymograms of the free esterase fraction visualized with NA as substrate were qualitatively similar at 5-12 days of age to the electrophoretic patterns observed in adult material. In both adult and developing brain, zymograms of bound esterase resembled those of the free enzyme, the major difference being the presence in the former of a slow, broad, anodic zone of diethyl-p-nitrophenyl phosphate-inhibited enzyme. Esterases characteristic of adult white matter and having preferential affinity for alpha-naphthylpropionate, alpha-naphthyl butyrate and alpha-naphthyl valerate were not identified in infant brain until about 4 months postnatal age. A far-moving, anodic enzyme was distinctly evident in zymograms of brains of less than 1 month of age. This enzyme hydrolysed NP, NB, and NV more actively than alpha-naphthyl acetate. It was present in the adult brain but, in contrast to the infant, was no longer electrophoretically-separable from another enzyme which had greater affinity for NA and had previously been designated the A10 band. Quantitative assays demonstrated that the bound esterase increased in cerebral and cerebellar cortex during development. In contrast, the proportion of free to bound esterase showed little change in white matter. Acetylcholinesterase and butyrylcholinesterase zymograms became identical to adult patterns from 1 to 4 months of age. Thiolacetic acid esterase was present at 38 weeks gestation. Some functional and anatomical correlations were attempted in explanation of the biochemical observations.

Journal ArticleDOI
TL;DR: Histochemical methods showed that tuber tissue and tissue culture cells of Solanum tuberosum contained phase-dense particles which absorbed neutral red and fluorescent dye, and particles which contained acid phosphatase and a non-specific esterase, which may be comparable to the lysosomes of animal tissues and theLysosome-like structures of plant cells which possess similar and additional properties.
Abstract: SUMMARY: Histochemical methods showed that tuber tissue and tissue culture cells of Solanum tuberosum contained phase-dense particles which absorbed neutral red and fluorescent dye, and particles which contained acid phosphatase and a non-specific esterase. It is suggested that these structures may be comparable to the lysosomes of animal tissues and the lysosome-like structures of plant cells which possess similar and additional properties. During infection of Solanum tissues by Phytophthora erythroseptica there was swelling and disruption of these host cell particles, accompanied by the release of acid phosphatase and esterase. Biochemical assay for acid phosphatase confirmed that infection of host cells resulted in the liberation of acid phosphatase from a particulate to the supernatant fluid fraction of cell homogenates.

Journal ArticleDOI
TL;DR: Tissue specificity of the esterases of two closely related species, Drosophila aldrichi and D. mulleri, is determined by starch gel electrophoresis of dissected tissues and organs and an esterase staining technique.
Abstract: Tissue specificity of the esterases of two closely related species, Drosophila aldrichi and D. mulleri, is determined by starch gel electrophoresis of dissected tissues and organs and an esterase staining technique. The determination of esterase homology between the two species is supplemented by tissue specificity as an added criterion of catalytic properties. General biological functions of some of the esterases are suggested by their presence in certain tissues. The potential usefulness of knowledge of tissue specificities in evolutionary and population genetic studies is discussed.

Journal ArticleDOI
TL;DR: In this article, a highly purified esterase preparation from Streptomyces griseus protease (Pronase), active against benzoylarginine ethyl ester, was inactivated with [32P]DFP and hydrolysed with HCl.