Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.1.8 (cholinesterase)
12,691 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human serum cholinesterase (EC 3.1.1.8) is a carbohydrate-rich glycoprotein, which reacts with 18 different lectins from plants and invertebrates by a specific precipitin reaction; most of the lectins combine with alkali-stable bound carbohydrate chains. One third of these lectin receptors appear after neuraminidase-treatment, two thirds can be demonstrated before and after removal of neuraminic acid. The specific lectin receptors of the alkali-labile carbohydrate chains are characterized and analyzed by chemical and serological methods.
...
PMID:[Serum cholinesterase as a model glycoprotein (author's transl)]. 41 80

Lectins from Canavalia ensiformis, Phaseolus vulgaris, and Triticum vulgare react with arylamidase, alkaline phosphatase, gamma-glutamyltransferase, and cholinesterase of human sera by formation of enzymatically active, mostly insoluble complexes. Arylamidase, alkaline phosphatase, and cholinesterase react more intensely in sera of healthy people than in sera of patients with liver and neoplastic diseases. Arylesterase is bound to a distinct degree only by concanavalin A. The enzymes mentioned above also react slightly with the following lectins in order of decreasing intensity: Ricinus communis, Arachis hypogaea, Helix pomatia, Glycine max, Dolichos biflorus, and Ulex europaeus. Though multiple forms containing less sialic acid are favourably bound, preincubation with neuraminidase does not improve the reaction except with soybean lectin. Since higher concentrations of lectins react also with fast moving fractions of high sialic acid content, no steric hindrance of the binding between lectins and sialoenzymes is supposed, as concluded from determination of the total enzyme activity.
...
PMID:[Lectins as reagents for the differentiation of serum enzymes. Lectins as reagents, I. (author's transl)]. 54 35

Differences in glycosylation of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in human brain, plasma and cerebrospinal fluid (CSF) have been investigated by means of their interaction with agarose-immobilized lectins. Most of the AChE in brain and CSF was associated to concanavalin A (Con A), Lens culinaris (LCA) and Triticum vulgaris (WGA) agglutinins, but little activity was adsorbed to Ricinus communis agglutinin I (RCAI). Brain, plasma and CSF BuChE was almost fully bound to Con A, LCA and WGA-agarose. Brain BuChE was unable to react with RCA (RCA-BuChE), the plasma enzyme was completely bound to the lectin (RCA+BuChE) and BuChE from CSF of normal children was partially fixed to RCA (RCA +/- BuChE). BuChE in CSF of children with meningitis fully reacts with the lectin. The data suggest that the proportion of RCA+BuChE in CSF of children with meningitis is increased, this enzyme probably coming from plasma.
...
PMID:Ricinus communis agglutinin I reacting and non-reacting butyrylcholinesterase in human cerebrospinal fluid. 146 69

Differentiation of individual rhombomeres of the chicken hindbrain directly follows the emergence of primary brain vesicles. Immediately after the constriction of the prosencephalon at HH9, a series of vesicles of decreasing size is established almost simultaneously between HH9 and HH10, including mesencephalon, four preotic (R2-R5) and one postotic (R6/R7) rhombomeres. Thereby, the cranial neural tube is ventrally embedded in a mesodermal PNA-binding matrix that particularly accumulates underneath vesicular constriction sites, as demonstrated for the segregation of the prosencephalon at HH9 and the cerebellar rhombomere R1 from R2 at HH13. The subsequent period of hindbrain differentiation is analyzed by cholinesterase (AChE, BChE) and peanut lectin histochemistry, by the BrdU and the neurite-specific G4 antibodies. Preotically, differentiation of two pairs of rhombomeres (R4 + R5, R2 + R3) starts in R4, immediately followed by R2. The caudal rhombomeres of both pairs are delayed (R5, R3). Then the postotic rhombomere is subdivided, whereby R7 differentiates before R6. Thus, the development in the direct vicinity of the otic vesicle is delayed (R5, R6). R7 is the last rhombomere that is demarcated caudally. Based on these findings, we postulate two processes that may regulate rhombomere formation in the chicken embryo: (a) an early rostrocaudal wave establishing the major brain vesicles, (b) a superimposed pairwise segmentation emanating rostrally and caudally from the otic vesicle. The segregation of the cerebellar rhombomere is a late step.
...
PMID:Patterning of chick brain vesicles as revealed by peanut agglutinin and cholinesterases. 169 41

Liver and plasma acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase activities of the chick embryo and adult chickens were separated by sucrose density gradient sedimentation and further differentiated by their lectin affinities and organophosphate sensitivities. Changes in plasma cholinesterases during development indicated a characteristic shift in tetrameric (G4) isoforms from a slightly larger G4 AChE in the embryo to G4 BChE in the adult. These changes were not reflected in isoform patterns of liver homogenates, however. Interestingly, the time course of an increase in plasma BChE activity corresponded to the time course of a decrease in liver BChE activity, as if this enzyme was being mobilized and released. The distribution of liver esterases included both monomeric (G1) and G4 BChE and a large p-nitrophenylacetate (p-NPA) esterase activity that was separated into two main peaks by density gradient ultracentrifugation. The effects of organophosphate inhibitors indicated that the two liver p-NPA esterase activities may be regarded as carboxylesterases; however, these enzymes showed very different sensitivities to paraoxon and diisopropylfluorophosphate (DFP), with IC50 values differing by 3 and 4 orders of magnitude. Lectin affinity studies with multiple esterase forms suggested a heterogeneous group of glycoproteins that were packaged at different sites in the liver cell and were consistent with the presence of an intracellular precursor form to plasma BChE.
...
PMID:Multiple molecular forms and lectin interactions of organophosphate-sensitive plasma and liver esterases during development of the chick. 224 23

On polyacrylamide gradient gel electrophoresis, normal serum cholinesterase was separated into seven isozymes (I-VII from the anodic to the cathodic side). The enzyme of the conditioned medium of the HuH-7 cell line, established from a human hepatoma, had two main isozymes. The one migrating faster was located slightly to the cathodic side of band II of the normal serum enzyme, and the other, a slower one, electrophoresed at the same position as that of band VI of the normal serum enzyme. Aside from these two isozymes, a faint band with enzyme activity sometimes appeared at a position just cathodic or very close to the position of band I of the normal serum isozymes. The effect of some inhibitors and activators on both the normal serum enzyme and the enzyme of the conditioned medium was similar, but lectin-binding properties of the two enzymes were different with Ricinus communis agglutinin I, concanavalin A and wheat germ agglutinin. These results suggest that the difference in sugar moieties of both enzymes is expressed in D-galactose, D-mannose and N-acetylglucosamine.
...
PMID:Novel cholinesterase expression in the HuH-7 cell line. 303 81

Embryonic retinae from 5-6-day-old chicks (E5-E6) were cut into stripes either in close contact with (RPE stripes) or in absence of the neighboring retinal pigmented epithelium (R stripes). The stripes were explanted and cultivated in vitro for up to 6 days, during which time they show the following differences in their characteristics of growth and differentiation. Compared with R stripes, RPE stripes morphologically showed a significant increase in size during the first 2 days in culture. Using E5 tissue, this is also demonstrated by a higher rate of cell proliferation (as measured by uptake of radioactive thymidine as well as by DNA contents). In contrast, R stripes after two days in culture show a much stronger neurite growth. After longer periods of culturing (5-6 days) we can show by cholinesterase histochemistry (AChE and BChE) and by PNA-lectin binding that the RPE stripes have started to form all major layers of the in vivo retina, whereas R stripes remain unstratified and start to degenerate earlier. We conclude that the pigment epithelium might exert a specific stimulus on growth and tissue differentiation of the neural retina not only during in vitro, but possibly also during in vivo development. The in vitro methods introduced here could become useful model systems to further investigate the significance of the RPE for developmental, regenerative and even adult processes of the neural retina. Their future applicability in ophthalmologic research is briefly discussed.
...
PMID:The pigmented epithelium sustains cell growth and tissue differentiation of chicken retinal explants in vitro. 338 24

We estimated the concentrations, multiple forms, and lectin binding of five microsomal enzymes in particle free extracts from human kidney, pancreas, jejunal mucosa, and normal and cancerous liver. While arylesterase markedly reacted only with concanavalin A, arylamidase, alkaline phosphatase, gamma-glutamyltransferase, and cholinesterase were intensely precipitated by lectins from Ricinus communis 120, Canavalia ensiformis, Triticum vulgare and Phaseolus vulgaris S. Agglutinins from Glycine max, Arachis hypogaea and Ulex europaeus proved less effective. The reaction mainly depended on the origin of enzymes not on their species. Desialylation always decreased precipitation, and in extracts of normal liver parenchyma it even totally abolished precipitation, by Triticum vulgare lectin. Sialoenzymes therefore appear to be normal intracellular constituents. Differences between enzymes from normal and cancerous liver were not reflected by variant properties of the corresponding activities in sera. The same held true for multiple forms. The reasons for these differences are discussed.
...
PMID:[Catalytic concentration, multiple forms, and lectin affinity of microsomal enzymes from human tissues: lectins as reagents, II (author's transl)]. 612 Feb 6

The biochemical characterization of detergent-solubilized acetylcholinesterase (AChE) from subcellular particles of sheep platelets and the effects of different effectors on AChE activity from solubilized platelet crude membranes have been undertaken and studied. Solubilization of AChE with detergent increased the thermal stability of the enzyme from all particulate fractions. Solubilized AChE from the mitochondria-granule fraction was the most thermostable at 55 degrees C. The Km values against acetylthiocholine chloride and the Arrhenius plot obtained were very similar for the AChE from all the solubilized fractions. There were no differences in the ability of solubilized AChE from different subcellular fractions to bind concanavalin A (Con A). In solubilized platelet crude membranes, benzyl alcohol was a potent AChE inhibitor at a concentration of 10(-2) M, whereas ethanol was not. Mg2+ cations and, to a lesser extent, Ca2+ and Mn2+ cations, activated AChE at concentrations higher than 1 mM. Serine hydrolase inhibitors and cholinesterase-specific inhibitors were very effective in the inactivation of AChE, whereas EDTA and EGTA had no effect. Of all the monosaccharides tested, only N-acetylneuraminic acid exerted an inhibitory effect on AChE activity. Immobilized-lectin binding studies demonstrated the interaction of solubilized crude membrane-bound AChE with Con A, lentil lectin and wheat germ agglutinin. Taken together, these data suggest the presence of a unique form of the membrane-bound AChE which has at least alpha-mannose and N-acetylglucosamine residues in the glycan chain.
...
PMID:Biochemical characterization of sheep platelet acetylcholinesterase after detergent solubilization. 785 52

Three different homologues of butyrylcholinesterase (BChE) with 75-, 62-, and 54-kDa subunit size are isolated from adult chicken serum, and all show very low or zero enzyme activity. Although the active BChE from serum with a subunit size of 81 kDa forms tetramers, the 75-kDa protein is isolated as a dimer. The homology of the 75-kDa protein with active BChE is shown by immunoreactivity with BChE-specific monoclonal antibodies, by coisolation with the active BChE, and by their identical first six N-terminal amino acids. By deglycosylation of these proteins and by their differential lectin binding, we show that the active BChE is an N-glycosylated protein of the triantennary type, whereas the inactive 75-kDa protein is O-glycosylated. These data show for the first time the existence of (1) multiple inactive forms of BChE, (2) secreted inactive cholinesterases, because they are found in serum, and (3) an O-glycosylated cholinesterase. Because cholinesterases can regulate neurite growth in vitro by a nonenzymatic mechanism, these data strongly support that both inactive and active forms of BChE may be involved in noncholinergic communication, possibly depending on particular glycosylation patterns.
...
PMID:Novel inactive and distinctively glycosylated forms of butyrylcholinesterase from chicken serum. 820 36


1 2 3 Next >>

---