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

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

The presence of a butyrylcholinesterase (BuChE, EC 3.1.1.8) in the musocal cells of the chicken intestine was demonstrated by histochemical and biochemical methods. The study of its distribution, along the intestine from duodenum to rectum, showed that the jejuno-ileum possesses the highest activity. Sucrose gradient centrifugation revealed, in all intestinal areas, two globular forms with sedimentation coefficients of 4.3 S (G1 form) and 10.8 S (G4 form). The presence of Triton X-100 in the preparations did not modify the sedimentation profiles of these two forms which can be considered as soluble BuChE. The ratio of G1/G4-forms progressively decreases along the intestine from duodenum to rectum indicating a predominance of the G4 form in the areas where the activity is low. Our results are discussed in relation to other studies of globular forms of chicken BuChE.
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PMID:Characterization of cholinesterase molecular forms in the mucosal cells along the intestine of the chicken. 272 80

1. A cholinesterase activity was shown to be present in the homogenates of the gut mucosal cells from seven mammal species examined. 2. The distribution of the cholinesterase activity in the mucosal cells along the intestine differs from one species to another. This distribution is not correlated with that of the aminopeptidase which is a specific marker of the enterocyte plasma membranes. 3. Except rabbit, all the other species contain a (G4) globular tetrameric form and either a (G1) monomeric form (pig, ox) or a (G2) dimeric form (mouse, rat, sheep). Both (G1) and (G2) forms are found with the (G4) form in the mucosal cells of kitten and cat. The solubility characteristics of these various forms were studied by sucrose gradient centrifugations in the presence and the absence of 1% Triton X-100. 4. The mucosal cells from the studied species essentially possess either acetylcholinesterase (rabbit, kitten, cat) or butyrylcholinesterase (ox, pig, sheep, rat, mouse). These findings indicate that both enzymes probably present identical physiological functions in this cell type.
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PMID:Acetylcholinesterase and butyrylcholinesterase in the gut mucosal cells of various mammal species: distribution along the intestine and molecular forms. 290 75

A 20 S asymmetric (non-globular) form of acetylcholinesterase (AChE, E.C. 3.1.1.7) has been purified from 1-day chick muscle. This form is a hybrid molecule containing both AChE and butyrylcholinesterase (BuChE, E.C. 3.1.1.8) catalytic subunits, linked through a collagenous tail. However, the 20 S hybrid AChE/BuChE could not account for the total enzyme activities of AChE and BuChE in a high-salt/Triton X-100 extract of 1-day chick muscle. By applying AChE- and BuChE-specific monoclonal antibodies for immunoadsorption, homogeneous asymmetric AChE and BuChE forms were also identified in that extract. The homogeneous BuChE accounts for 20% of the total activity of the asymmetric BuChE present and sediments at 17 S. About 6% of the asymmetric AChE present is, likewise, in a homogeneous, instead of the hybrid, form. The 17 S asymmetric BuChE does not react with monoclonal antibodies specific for the collagenous tail of the hybrid 20 S AChE/BuChE molecule, suggesting that the collagenous subunit differs between these two forms.
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PMID:Identification of a 17 S asymmetric butyrylcholinesterase in chick muscle by monoclonal antibodies. 336 25

We report an analysis of the solubility and hydrophobic properties of the globular forms of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) from various Torpedo tissues. We distinguish globular nonamphiphilic forms (Gna) from globular amphiphilic forms (Ga). The Ga forms bind micelles of detergent, as indicated by the following properties. They are converted by mild proteolysis into nonamphiphilic derivatives. Their Stokes radius in the presence of Triton X-100 is approximately 2 nm greater than that of their lytic derivatives. The G2a forms fall in two classes. Class I contains molecules that aggregate in the absence of detergent, when mixed with an AChE-depleted Triton X-100 extract from electric organ. AChE G2a forms from electric organs, nerves, skeletal muscle, and erythrocyte membranes correspond to this type, which is also detectable in detergent-soluble (DS) extracts of electric lobes and spinal cord. Class II forms never aggregate but only present a slight shift in sedimentation coefficient, in the presence or absence of detergent. This class contains the AChE G2a forms of plasma and of the low-salt-soluble (LSS) fractions from spinal cord and electric lobes. The heart possesses a BuChE G2a form of class II in LSS extracts, as well as a similar G1a form. G4a forms of AChE, which are solubilized only in the presence of detergent and aggregate in the absence of detergent, represent a large proportion of cholinesterase in DS extracts of nerves and spinal cord, together with a smaller component of G4a BuChE. These forms may be converted to nonamphiphilic derivatives by Pronase. Nonaggregating G4a forms exist at low levels in the plasma (BuChE) and in LSS extracts of nerves (BuChE) and spinal cord (AChE).
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PMID:Amphiphilic and nonamphiphilic forms of Torpedo cholinesterases: I. Solubility and aggregation properties. 341 26

We report an electrophoretic analysis of the hydrophobic properties of the globular forms of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) from various Torpedo tissues. In charge-shift electrophoresis, the rate of electrophoretic migration of globular amphiphilic forms (Ga) is increased at least twofold when the anionic detergent deoxycholate is added to Triton X-100, whereas that of globular nonamphiphilic forms (Gna) is not modified. The G2a forms of the first class, as defined by their aggregation properties, are converted to nonamphiphilic derivatives by phosphatidylinositol phospholipase C (PI-PLC) and human serum phospholipase D (PLD). AChE G2a forms from electric organs, nerves, skeletal muscle, and erythrocyte membranes correspond to this type, which also exists in very small quantities in detergent-solubilized extracts of electric lobes and spinal cord. They present different electrophoretic mobilities, so that each of these tissues contains a distinct "electromorph," or two in the case of electric organs. The G2a forms of the second class (AChE in plasma, BuChE in heart), as well as G4a forms of AChE and BuChE, are insensitive to PI-PLC and PLD but may be converted to nonamphiphilic derivatives by Pronase.
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PMID:Amphiphilic and nonamphiphilic forms of Torpedo cholinesterases: II. Electrophoretic variants and phosphatidylinositol phospholipase C-sensitive and -insensitive forms. 341 27

Activity of acetylcholinesterase (EC 3.1.1.7) and pseudocholinesterase (EC 3.1.1.8) was measured in extracts from chick corneas, in a developmental series from days 7-20 of incubation and at three ages after hatching. Enzyme activity was measured by the biphasic single-vial radiometric assay of Johnson and Russell using [3H-acetyl]choline as substrate. Pseudocholinesterase was inhibited with tetraisopropylpyrophosphoramide (iso-OMPA). True acetylcholinesterase activity was verified by control assays run in the presence of both iso-OMPA and the true acetylcholinesterase inhibitor, 1:5-bis(4-allyldimethyl-ammonium phenyl)-pentane-3-one diiodide (BW284c51). With both inhibitors present, no cholinesterase activity was detected. Corneal acetylcholinesterase had an average Km of 1.1 +/- 0.3 X 10(-3) M at day 7, 14, and 20 of development and retained 90% activity even after 3 hr at 26 degrees C. At least 90% of the total cholinesterase activity was solubilized by Triton X-100 and sonication treatment. Activity decreased with increasing concentrations of NaCl present in the assay. A 60-fold transient increase in acetylcholinesterase specific activity occurs during the period from days 7-20 of embryonic development. This increase begins on the first day measured (day 7), progresses steadily and rapidly during the subsequent week, reaches a peak at day 15, and then decreases rapidly before hatching to a level maintained into adulthood. A similar pattern of transient appearance of highly sialylated gangliosides seen previously on days 14-17 leads to an hypothesis of a structural linkage between acetylcholinesterase and the plasma membrane lipids of corneal epithelial cells.
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PMID:Acetylcholinesterase activity in the cornea of the developing chick embryo. 357 Jun 95

The embryonic development of total specific activities as well as of molecular forms of acetylcholinesterase (AChE, EC 3.1.1.7) and of butyrylcholinesterase (BChE, EC 3.1.1.8) have been studied in the chick brain. A comparison of the development in different brain parts shows that cholinesterases first develop in diencephalon, then in tectum and telencephalon; cholinesterase development in retina is delayed by about 2-3 days; and the development in rhombencephalon [not studied until embryonic day 6 (E6)] and cerebellum is last. Both enzymes show complex and independent developmental patterns. During the early period (E3-E7) first BChE expresses high specific activities that decline rapidly, but in contrast AChE increases more or less constantly with a short temporal delay. Thereafter the developmental courses approach a late phase (E14-E20), during which AChE reaches very high specific activities and BChE follows at much lower but about parallel levels. By extraction of tissues from brain and retina in high salt plus 1% Triton X-100, we find that both cholinesterases are present in two major molecular forms, AChE sedimenting at 5.9S and 11.6S (corresponding to G2 and G4 globular forms) and BChE at 2.9S and 10.3S (G1 and G4, globular). During development there is a continuous increase of G4 over G2 AChE, the G4 form reaching 80% in brain but only 30% in retina. The proportion of G1 BChE in brain remains almost constant at 55%, but in retina there is a drastic shift from 65% G1 before E5 to 70% G4 form at E7.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Quantitative development and molecular forms of acetyl- and butyrylcholinesterase during morphogenesis and synaptogenesis of chick brain and retina. 358 28

Developmental regulation, from the fetal period to 11 months of age, and the influence of denervation on the appearance and disappearance of the molecular forms of acetylcholinesterase (AchE) and butyrylcholinesterase (BuchE) in rat skeletal muscle were examined. The enzyme forms were extracted from anterior tibialis in 0.01 M sodium phosphate buffer, pH 7.0, containing 1 N NaCl, 0.01 M EGTA, 1% Triton X-100, and a cocktail of antiproteases, and analyzed by velocity sedimentation on 5-20% linear sucrose gradients. Three principal forms, denoted by sedimentation coefficients of 4, 10.8, and 16 S, were observed in muscle from all age groups. The amounts of each of the molecular forms of AchE and BuchE in skeletal muscle exhibited distinct and reciprocal patterns of appearance and disappearance during pre- and postnatal development. In tissue derived from animals less than 2 weeks of age, BuchE represented the predominant component of activity in the 4 S form, was present equally with AchE in the 10.8 S form, and was subordinate to AchE in the 16 S form. Between 1 and 2 weeks of age a progressive increase in AchE activities coincident with a reduction in BuchE activities resulted in inversion in the amounts of the two enzymes present in adult muscle. Denervation of muscle caused a dramatic reduction in the presence of AchE molecular forms with no discernable influence on the presence of BuchE molecular forms. These results indicate that biosynthesis of BuchE is strictly regulated in a reciprocal manner with that of AchE, and that BuchE metabolism is independent of the state of muscle innervation. Increased synthesis of AchE and either reduced synthesis or increased degradation of BuchE can account for the reciprocal regulation of these enzymes. These characteristics of mammalian muscle contrast sharply with characteristics deduced for avian tissue (Silman et al. (1979) Nature (London) 280, 160-162). The innervation-independent metabolism of BuchE and the diverse modes of its regulation in different tissue from different species signify that BuchE function may be unrelated to cholinergic neurotransmission.
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PMID:Reciprocal regulation of acetylcholinesterase and butyrylcholinesterase in mammalian skeletal muscle. 381 86

L. W. Haynes and M. E. Smith have reported [(1985) Biochem. Soc. Trans. 13, 174-175] that glycyl-L-glutamine (Gly-Gln) increases the A12 and G4 forms of acetylcholinesterase (AcChoEase) in cultured embryonic rat skeletal muscle. Since Gly-Gln meets the criteria established for the neurotrophic factor (NF) in extracts of central nervous system/sciatic nerves that maintains AcChoEase and butyrylcholinesterase (BtChoEase) in the denervated cat superior cervical ganglion (SCG) in vivo, it was tested by the latter procedure. Solutions of Gly-Gln (10(-7)-10(-3) M) in 0.9% NaCl solution were infused for 24 hr via the right common carotid artery of cats with preganglionically denervated SCG, following ligation of the external carotid and lingual arteries. At 48 hr postdenervation, the AcChoEase and BtChoEase contents of the right SCG were within the range of similarly treated controls infused with 0.9% NaCl solution; the AcChoEase and BtChoEase contents of the left SCG, where the infused solutions arrived by way of a much more circuitous route, were significantly elevated at concentrations of Gly-Gln of 10(-5) M and higher. This suggested that the neurotrophic effect on the left SCG was produced by a metabolite of Gly-Gln. Accordingly, glycine, L-glutamine, and glycyl-L-glutamic acid (Gly-Glu) were then tested. Glycine and L-glutamine were inactive; Gly-Glu, 10(-6)-10(-5) M, exerted a significantly positive neurotrophic effect at both the right and left SCG; at 10(-4) M, the effect was absent. The method employed currently for preparation of extracts of SCG for assay of AcChoEase, BtChoEase, and protein contents (homogenization of scissor-minced ganglia in water) was compared with homogenization in molar NaCl/1% Triton X-100. Values obtained by the former procedure, in comparison with the latter, were 91% +/- 7% for AcChoEase and 83% +/- 7% for BtChoEase, expressed as substrate hydrolyzed per mg of protein per min.
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PMID:Glycyl-L-glutamine, a precursor, and glycyl-L-glutamic acid, a neurotrophic factor for maintenance of acetylcholinesterase and butyrylcholinesterase in the preganglionically denervated superior cervical ganglion of the cat in vivo. 386 Aug 56

Acetylcholinesterase (AChE; EC 3.1.1.7) extracted in 1% Triton X-100 from rabbit brain was purified 2,000-fold by chromatography on agarose conjugated with a monoclonal antibody directed against human red blood cell cholinesterase. After elution from the immunoadsorbent with pH 11 buffer, the preparation was purified further by affinity chromatography on phenyltrimethylammonium-Sepharose 4B with decamethonium elution. Overall yield of purified enzyme was 37% of the AChE originally solubilized, with a specific activity of 2,950 units/mg protein. Electrophoresis under reducing conditions in 7.5% sodium dodecyl sulfate polyacrylamide gels revealed only one silver-staining polypeptide band. A streamlined purification procedure enabled the isolation of electrophoretically homogeneous AChE to be completed in fewer than 7 days, at yields exceeding 50%. Electrophoretic analysis of purified AChE indicated an apparent MW of 71,000 for the monomeric subunit. Gel filtration and sucrose density gradient centrifugation in the presence of Triton X-100 showed little difference between the properties of the native and the purified enzyme. The molecular mass of the main species was estimated from the gel filtration and sedimentation data to be 280,000 daltons. Kinetic parameters of the purified protein (Km = 0.16 +/- 0.01 mM) were close to those of the native enzyme (Km = 0.12 +/- 0.01 mM) when examined with acetylthiocholine iodide as substrate. The two-step immunopurification procedure presented in this communication offers a convenient route to homogeneous neural AChE in quantities useful for detailed biochemical and immunochemical study.
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PMID:Two-step immunoaffinity purification of acetylcholinesterase from rabbit brain. 396 30


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