Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.37 (CNPase)
 539 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enzymatic cycling procedure for beta-NADP+ generated by the enzyme 3'-phosphodiesterase, 2':3'-cyclic nucleotide (EC 3.1.4.37) from its substrate 2':3'-cyclic NADP+ is described. The enzymes glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and diaphorase (EC 1.8.1.4) are used to cycle the cofactor between its oxidized and reduced forms in the presence of glucose-6-phosphate and p-iodonitrotetrazolium violet (INT) with the concomitant production of colored INT-formazan, monitored at 492 nm. The amplification is about 400-fold per hour and is sensitive enough to detect 6 x 10(-13) mol of NADP(H). A simple procedure for the optimization of this cycling assay is also described. Conjugates to 3'-phosphodiesterase, 2':3'-cyclic nucleotide may be used in heterogeneous enzyme immunoassays for the detection of small quantities of haptens or proteins in biological fluids.
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PMID:An enzymatic cycling procedure for beta-NADP+ generated by 3'-phosphodiesterase, 2':3'-cyclic nucleotide. 132 Mar 51

Myelin was isolated from bovine brain by several published procedures and modifications of these procedures. High activity of the myelin marker (2',3'-cyclic nucleotide 3'-phosphohydrolase) and low activity of contaminants markers in white matter homogenates in respect to cerebral cortex showed the white matter to be better than the cerebral cortex or the whole brain for myelin isolation. A procedure is described for the preparation of purified myelin from bovine white matter which yielded a content of protein (40%), myelin marker (51%), and 5'-nucleotidase (25%) in purified myelin higher than by any used method. Acetylcholinesterase or succinate dehydrogenase was lower than 7% of its activity in the white matter homogenate, and monoamine oxidase and NADPH:cytochrome c reductase were not recovered in myelin fraction. Morphologically, myelin fraction was shown to mainly consist of multilamellar membranes of different sizes. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of myelin fraction showed a characteristic protein pattern of myelin. When our procedure was applied to frozen white matter, lower protein (32%) and myelin marker (34%) and similar 5'-nucleotidase activity (24%) were recovered in myelin, increasing its recovery in denser fractions of white matter.
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PMID:Isolation and characterization of bovine brain myelin distribution of 5'-nucleotidase. 283 88

Bovine splenic nerve was used as a source of axolemma-enriched fractions derived from mammalian unmyelinated axons. By electron microscopy, splenic nerve consisted entirely of fascicles of unmyelinated axons and associated Schwann cells. The epineurium and blood vessels were stripped from the dissected nerve, which was then homogenized followed by preparation of a microsomal fraction by differential centrifugation. The microsomes were fractionated on a 10% to 40% continuous sucrose gradient. The individual fractions were combined into six fractions based on sucrose concentration and each fraction was analyzed for membrane markers. The 20% to 23% region of the sucrose gradient was enriched approximately sevenfold in acetylcholinesterase activity and twofold enrichment in saxitoxin binding activity was noted in the same fraction. Relative to other microsomal fractions, this same fraction was less enriched in a microsomal marker (cytochrome c reductase) and only moderately enriched in the activity of a myelin membrane marker (2',3' cyclic nucleotide 3' phosphohydrolase, CNPase). Polyacrylamide electrophoresis of the axolemma-enriched fraction revealed five prominent peptides ranging in molecular weight from 40 kDa to 130 kDa. Lipids, comprising 59.4% of the dry weight, were enriched in cholesterol and sphingomyelin, consistent with the origin from a peripheral nervous system (PNS) plasma membrane. On a molar basis, the major gangliosides were G(T1b), G(D1a), and G(M1). As a whole, these molecular characteristics are consistent with the origin of the axolemma-enriched fraction in the unmyelinated splenic nerve axons. This membrane preparation should prove useful in future studies of the myelinogenic potential of mammalian unmyelinated axolemma.
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PMID:Isolation and characterization of unmyelinated axolemma from bovine splenic nerve. 1046 91