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PubMed1986

Reactivity patterns of monoclonal antibodies positive on myelomonocytic leukemia cells as defined by esterase isoenzyme analysis.

The reactivity with monoclonal antibodies (MoAbs) specific for myelomonocytic cells and the expression of a particular esterase isoenzyme were analyzed in 159 cases of acute myeloid leukemias. The incidence of positivity of 16 MoAbs (MCS-2, MCS-1, OKM1, My-1, Leu-M1, Leu-M3, CA-2-38, MY4, MY7, MY8, MY9, VIM-D2, VIM-D5, Mo1, Mo2, 63D3) was studied using the indirect immunofluorescence technique. A carboxylic esterase isoenzyme which can be inhibited completely and selectively by sodium fluoride (NaF) was demonstrated by isoelectric focusing on horizontal polyacrylamide gels. This NaF-sensitive isoenzyme indicated the monocytic origin of the blast cells as it is specific for this cell lineage. Prior to the immunological-isoenzymatic analysis all cases were categorized into two subtypes according to morphological criteria of the FAB classification system: 147 cases of AML (FAB M1-3) and 12 cases of AMMoL/AMoL (FAB M4/5). However, 15 out of 147 cases of AML expressed the NaF-sensitive isoenzyme and were therefore assigned to the group AMMoL/AMoL. Likewise, 1 case, diagnosed morphologically as AMMoL, was negative for this marker isoenzyme and was assigned to the other leukemia subtype. The incidence of reactivity varied widely for the MoAbs tested regarding the overall results on all cases and the positivity of cases of either AML or AM-MoL/AMoL. The MoAbs were grouped into four classes depending on the pattern of reactivity with myeloblastic or monoblastic or both subtypes of acute myeloid leukemia. The MoAbs MCS-2, MY7, Leu-M1, and MY9 detected the vast majority of cases with either myelocytic or monocytic involvement (group-I: "pan-myelomonocytic" reactivity). The MoAbs MCS-1, OKM1, VIM-D5, and Mo1 showed a predominance in their staining pattern for monocytic variants, but were also positive on a substantial percentage of nonmonocytic cases (group-II: predominantly reactive with monocytic, but also myelocytic cases). The MoAbs Leu-M3, MY4, VIM-D2, Mo2, and MY8 reacted with the large majority of AMMoL/AMoL cases and with a small number of AML cases (group-III: monocyte-"specific" reactivity). The MoAbs of group-I are useful in differentiating acute lymphoid from acute myeloid leukemias. The MoAbs of group-III, and to a lower extent those of group-II, will be of considerable value in the subtyping of acute myeloid leukemias. The results show that accuracy of leukemia classification might not always be achieved by morphology alone, but that immunological and biochemical aspects should be included as well, and several MoAbs are very useful tools for classification and subtyping of acute myeloid leukemias.

Antibodies, Monoclonal↗
PubMed1994

Mutations affecting a regulated, membrane-associated esterase in Salmonella typhimurium LT2.

Mutations at the apeA locus in Salmonella typhimurium lead to loss of a soluble enzyme ("protease I") that hydrolyzes the chromogenic endoprotease substrate N-acetyl phenylalanine beta-naphthyl ester. We have isolated pseudorevertants of S. typhimurium apeA mutations that have regained the ability to hydrolyze this compound. These pseudorevertants contain mutations (apeR) that lead to overproduction of a membrane-bound esterase different from protease I. The apeR locus is phage P1 cotransducible with ilvC (83 map units) and is unlinked to apeA. Mutations at still another locus, apeE, lead to loss of the membrane-associated esterase. The apeE locus is P1 cotransducible with purE (12 map units). In an apeE-lacZ operon fusion strain, an apeR mutation increases the level of beta-galactosidase approximately 60-fold. We propose that apeR encodes a repressor of apeE. The evidence available suggests that the ApeE protein is not a protease.

Esterases↗
PubMed1986

The major gut esterase locus in the nematode Caenorhabditis elegans.

Mutations in the major gut esterase of the nematode Caenorhabditis elegans have been induced by ethylmethane sulfonate and detected by isoelectric focusing. The gut esterase locus, denoted ges-1, maps less than 0.3 map units to the right of the unc-60 locus, at the left end of chromosome V.

Animals↗
PubMed1988

Proximity of the CTLA-1 serine esterase and Tcr alpha loci in mouse and man.

The serine esterase CTLA-1 gene was shown by in situ hybridization to map to the D segment of mouse chromosome 14, the same localization as a member of the immunoglobulin superfamily, Tcr alpha. To further demonstrate the proximity of CTLA-1 and Tcr alpha, genetic linkage was tested in mouse using restriction fragment length polymorphisms and a backcross progeny, and no recombination was observed in the 100 backcross products studied. Recombination events between Tcr alpha/CTLA-1 and the markers Gdh-X and NP-1 show that the most probable order of these loci in the mouse 14D region is NP-1-Tcr alpha/Ctla-1-Gdh-X. In man, the human homologue of CTLA-1 was shown by in situ hybridization to map on chromosome 14, at 14q11-q12, where Tcr alpha also maps. Using the human cell line SUP-T1, bearing the inversion inv(14) (q11;q32), we further demonstrated the loci order in man to be centromere-NP-1-Tcr alpha-CTLA-1. To complement the cytogenetic and genetic mapping data, we tried to determine the physical distance between the two genes by pulsed field gel electrophoresis (PFGE). DNA prepared from various cell types, both mouse and human, were digested with a panel of rare cutter enzymes and hybridized first with CTLA-1, then with Tcr alpha probes. None of the bands identified hybridized with both Tcr alpha and CTLA-1 probes for either mouse or human cells. Although the physical mapping by PFGE is inconclusive, the cytogenetic and genetic data support close linkage of the Tcr alpha and CTLA-1 genes in both mouse and man, suggesting homology between the D region of mouse chromosome 14 and the q11-q12 region of human chromosome 14, encompassing the Tcr alpha and CTLA-1 loci. These findings also provide another example of proximity of genes coding for a member of the Ig super-family and a serine esterase.

Animals↗
PubMed1976

Studies on the host-parasite interaction and role of esterases during biting of the Indian cattle leech, Poecilobdella granulosa.

Histochemical localization of acetylcholinesterase and butyrylcholinesterase in the salivary glands has unfolded the significant fact that salivary glands are of two types, one being enzymatically negative and the other showing positive activity. Activity of these enzymes has been linked with the operation of glandular dynamics, particularly concerning the synthetic and secretory processes. The enzymes have been seen localized in the core of jaw. Contrary to it they are absent in the papillary and interpapillary zones of the jaw. Absence of esterases in the papillary and interpapillary ductules has been correlated with its possible non-involvement in the synthesis of vasodilating and anticoagulating materials. The experiments on effect of biting on host tissue give a faint indication of vascular dilation due to bite. Likewise, experiments on enzymatic state of a salivary gland after leech-bite reveal that the diminution of the reactive coverage area in the salivary glands reaches its maximum in the case of ATPase, indicating thereby its more involvement in salivary functions than those of esterases and acid phosphatase.

Acid Phosphatase↗
PubMed1983

Tissue localization of esterase-5 in Drosophila pseudoobscura.

Disc gel electrophoresis of dissected adults of Drosophila pseudoobscura showed that most of the esterase-5 activity was in the head (36%) and thorax (51%), with little activity in the abdomen (13%). No activity was found in digestive tissues, reproductive tissues, or nervous tissues. Most of the est-5 activity (61%) was found to be associated with hemolymph. However, the eyes contained 39% of the total est-5 activity. These results were supported by spectrophotometric assays of esterase activity in crude extracts of eyes and whole flies without eyes which showed that 27% of the total est-5 activity was in the eyes.

Abdomen↗
PubMed1976

The activity of non-specific esterase in the thyroid epithelial cells of the guinea pig as influenced by various inhibitors and activators. A histochemical study.

The action of various inhibitors and activators upon esterase activity in the thyroid epithelial cells is demonstrated. The agents used were triorthocresylphosphate (TOCP), parachloromercuribenzoate (PCMB), Arsanillic acid, p-nitrophenyl dimethyl carbamate and bis p-nitrophenyl phosphate. TOCP was found to inhibit selectively the activity in the follicle cells proper when alpha naphthyl acetate was used as a substrate. Arsanillic acid (0,001 M) activated the follicle cells proper selectively, but if the concentration was raised to 0,01 M the effect was that of inhibition while the activity in the para-, inter- and intrafollicular cells was unchanged. The results obtained are related to previous biochemical and histochemical observations and the nature of esterases in the thyroid is discussed.

Acetylesterase↗
PubMed1976

SH groups in the alpha-naphthyl acetate esterase in the thyroid of the guinea-pig. A histochemical study.

The alpha-naphthyl acetate esterase in both group I and group II thyroid cells is shown to contain SH groups since there is a decline in activity in both cell groups when certain sulfhydryl reagents [DTNB; 5,5'-Dithiobis-(2-nitrobenzoic acid)-AgNO3-Mersalyl-PCMB (parachloro mercuribenzoate) + urea] are added to the incubation media. Thus the inhibition is by far the greatest in group I cells, which also show the greatest activity after incubation in conventional media, when long fixation and storage times are used. In all cases the inhibiting effect was complete or almost completely reversed if cysteine was added to the incubation media in equivalent concentrations to the SH blocker. There were great differences among the sulfhydryl reagents used in their ability to bring about enzyme inhibition. The alkylating agents NEM (N-ethylmaleimide) and iodoacetamide had no or little effect while PCMB could only inhibit the activity of the alpha-naphthylacetate esterase if the enzyme was denaturated with 5 M urea. The maximal inhibitory effect of PCMB was only obtained when NaCl was added to the incubation media. The most effective inhibitor was AgNO3.

Animals↗
PubMed1986

Distribution and probable physiological role of esterases in reproductive, digestive, and fat-body tissues of the adult cotton boll weevil, Anthonomus grandis Boh.

Polyacrylamide gel electrophoresis was used to examine gut, Malpighian tube, fat-body, testes, and ovarioles tissues of the adult cotton boll weevil, Anthonomus grandis Boh. Esterases for which the inheritance has been reported previously by Terranova using whole-body homogenates were detected in dissected tissues and the probable physiological function of each allozyme is suggested. EST-1 occurs most frequently in ovarioles and female fat bodies. EST-2 is most often found in fat bodies and may be important in lipid turnover. No sex difference was observed. EST-3S is found in fat bodies and reproductive tissue, while EST-3F is always located in gut tissues, indicating that EST-3 is not controlled by a single autosomal locus with two codominant alleles as previously reported. EST-4, the most abundant esterase, can be detected in gut tissue at any age and is probably involved in digestion. EST-5 contains four allozymes which appear most frequently in testes and may be important during reproduction.

Adipose Tissue↗
PubMed1981

Demonstration of calcium-dependent chemotactic factor activatable esterase activity in human neutrophils: relationship with chemotaxis and chemotactic deactivation.

An increase in esterolytic activity, as measured by [3H] BAEE hydrolysis, was demonstrated in human neutrophil suspensions following incubation with three distinct chemotactic factors. The increased activity was demonstrated in intact cells as well as in cell lysates. The FMLP-enhanced enzymatic hydrolysis of BAEE was found to be calcium dependent. Esterase activation by FMLP was maximal at 1.0 mM of added calcium. Similar dose-response curves for esterase activation, chemotaxis, and chemotactic deactivation were obtained with the chemotactic factor FMLP, suggesting that in human neutrophils all three functions utilize some of the same early molecular events following chemotactic factor binding to th neutrophil surface.

Arginine↗
PubMed1980

Control of leukocyte functions. Role of internal H+ concentration and a membrane-bound esterase.

An activable membrane-bound neutral esterase which responds to many of the known leukocyte cytotaxins and appears to be involved in several membrane functions of these cells is described. Activation of this enzyme is associated with excretion of H+, O2-, and lysosomal enzymes; aggregation of intact cells and isolated membranes; activation of glucose oxidation; and changes in cellular motility. Conditions which alter the activity of this enzyme, e.g., addition of H+ or of synthetic hydrophobic peptides or esters (whose hydrolysis liberates H+ within or on these membranes) or by repeated washing of the cells (which partially removes this enzyme from the cells), all markedly alter rates of the above cellular functions. Although the native membrane substrate for this enzyme is not yet identified, the enzyme appears not to be involved in gamma-glutamyl transpeptidase reactions. Rather the data support the concept that hydrolysis by the enzyme of membrane components (proteins) results in H+ and O2- efflux (as well as other cation fluxes) with resultant rise in intracellular pH. Under these conditions cell movement ceases. Agents, e.g., low concentrations of chemotactic peptides or proteins which inhibit H+ and O2- excretion accelerate motility. The presence of external hydrophobic substrates for this enzyme, whose hydrolysis liberates H+ in or on these membranes and also inhibits efflux of H+ and O2-, also optimizes motility. The esterase(s) thus appears to control many functions of these cells by controlling H+ efflux from these cells.

Cell Membrane↗
PubMed1983

The characterisation of an esterase derived from Babesia bovis and its use as a vaccine.

An esterase was isolated from a crude extract of Babesia bovis by affinity chromatography, using soy bean trypsin inhibitor as a ligand. In native form this enzyme had a molecular weight greater than 200 000, but on denaturing gels major bands were observed with molecular weights of 20 000, 10 000 and 7 000. Western transfer analysis revealed a major band with a molecular weight of 19 000-20 000. Both bovine and rabbit antisera avidly stained infected red cells, using indirect immunofluorescence. Weak parasite staining was also observed using this test. Two groups of five animals were vaccinated twice 4 weeks apart with esterase derived from 5 X 10(9) parasites as water-in-oil emulsions with Freund's complete adjuvant. Two control groups, each of five animals were also included. One group of vaccinates and a control group were challenged with virulent homologous B. bovis, whilst the other vaccinated and the remaining control group were challenged with virulent heterologous organisms. In the homologous groups two controls but no vaccinates died, whereas in the heterologous groups four animals in each group died. Significant differences in parasitaemia, temperature rise and total haemolytic complement were observed in the homologous vaccinated group compared to their controls but no differences were observed between heterologous groups.

Animals↗
PubMed1980

A simultaneous-coupling azo dye method for the quantitative assay of esterase using alpha-naphthyl acetate as substrate.

This paper describes a simultaneous-coupling azo dye method for the measurement of esterase activity using the histochemical substrate, alpha-naphthyl acetate. By the choice of two diazonium salts with optimal coupling characteristics, the reaction can be carried out at any pH between 3.0 and 9.5. The azo dye is maintained in solution for spectrophotometric measurements with bovine serum albumin. The simultaneous-coupling method is compared with an assay based on the direct measurement of released alpha-naphthol by its ultra-violet absorbance in a pH study of hog liver esterase. There is good agreement between the data obtained by both methods.

Animals↗
PubMed1992

Modification of aldehyde dehydrogenase with dicyclohexylcarbodiimide: separation of dehydrogenase from esterase activity.

Dehydrogenase activity of the cytoplasmic (E1) isozyme of human liver aldehyde dehydrogenase (EC 1.2.1.3) was almost totally abolished (3% activity remaining) by preincubation with dicyclohexylcarbodiimide (DCC), while esterase activity with p-nitrophenyl acetate as substrate remained intact. The esterase reaction of the modified enzyme exhibited a hysteretic burst prior to achieving steady-state velocity; addition of NAD+ abolished the burst. The Km for p-nitrophenyl acetate was increased, but physicochemical properties remained unchanged. The selective inactivation of dehydrogenase activity was the result of covalent bond formation. Protection by NAD+ and chloral, saturation kinetics, and the stoichiometry and specificity of interaction indicated that the reaction of DCC occurred at the active site of the E1 isozyme. The results suggested the some amino acid other than aspartate or glutamate, possibly a cysteine residue, located on a large tryptic peptide of the E1 enzyme, may have reacted with DCC.

Aldehyde Dehydrogenase↗
PubMed1995

Analysis of esterase zymograms of Fusarium sambucinum and related species.

Esterase zymograms were obtained following polyacrylamide slab gel electrophoresis of protein extracts Fusarium sambucinum and related species originating from different geographic locations and different matrices. The sites of esterase activity were recorded, and the Rfs were calculated. The data were used for the construction of phenograms by cluster analysis and nonlinear mapping by computerized classification techniques. The fifteen isolates of F. sambucinum, the eight isolates of F. torulosum and the six isolates of F. spec. nov. each had identical profiles, and are therefore electrophoretically distinct species. The isolates of F. sarcochroum, one of F. sambucinum sensu lato (BBA 64280) and fifteen isolates of F. sambucinum were electrophoretically indistinguishable from each other. We assume they are synonymous. The isolate of F. bacteridiodes, one of F. sambucinum sensu lato (BBA 64993) and eight isolates of F. torulosum had uniform EST patterns, therefore the two species are electrophoretically identical. We assume they are also synonymous. The remaining three isolates of F. sambucinum sensu lato are somewhat closely related to F. sambucinum isolates on the basis of our investigations.

Cluster Analysis↗
PubMed1995

Esterification in non-aqueous solvents: cholesterol esterase as a selective biocatalysator from porcine pancreas.

From commercial porcine pancreas extract (pancreatin, PPE) an enzyme (60 kDa) was isolated and purified to SDS-PAGE homogeneity by combined ammonium sulphate fractionation, hydrophobic interaction chromatography and gel permeation chromatography. Isoelectric focusing of the purified enzyme revealed several bands at pH 4.5-5.0 and at pH 6.5-8.0. The analysis of 20 N-terminal amino acids led to its identification as cholesterol esterase (EC 3.1.1.13). While lipase (PPL), also isolated and purified from PPE, did not show esterifying activity in organic solvent, cholesterol esterase catalysed the selective esterification of 2-pentanol with butanoic acid in heptane.

Amino Acid Sequence↗
PubMed1991

Lymphocyte activation and serine-esterase induction following recombinant interleukin-2 infusion for lymphomas and acute leukaemias.

In this study we investigated the pattern of T lymphocyte changes in 16 adult patients with acute myeloid leukaemia (8), non-Hodgkin's lymphoma (4) and Hodgkin's disease (4) treated with continuous infusion of recombinant interleukin-2 (rIL-2). Effects indicative of lymphocyte activation occurred even prior to any rIL-2 therapy in these patients, being most prominent in patients with active diseases. Following each course of cytokine therapy, there were further changes in these parameters. Significant rebound lymphocytoses occurred with a concomitant increase in the cytotoxic functions and induction of the cytotoxicity-linked cytoplasmic serine esterase. Hence, both the natural killer and lectin-dependent cellular cytotoxicity activities were up-regulated. There were also increases in the serum sIL-2 receptor, sCD4 and sCD8 levels. More CD3+ lymphocytes, especially cells bearing CD4, were also recruited to the pool of potential effector cells, as demonstrated by the greater proportion of cells expressing the cytoplasmic serine esterase.

Adult↗