Human brain and placental choline acetyltransferase: purification and properties

Biochemistry
R RoskoskiL M Roskoski

Abstract

Choline acetyltransferase (EC 2.3.1.6) catalyzes the biosynthesis of acetylcholine according to the following chemical equation: acetyl-CoA + choline in equilibrium to acetylcholine + CoA. In addition to nervous tissue, primate placenta is the only other animal source which contains appreciable acetylcholine and its biosynthetic enzyme. Human brain caudate nucleus and human placental choline acetyltransferase were purified to electrophoretic homogeneity using ion-exchange and blue dextran-Sepharose affinity chromatography. The molecular weights determined by Sephadex G-150 gel filtration and sodium dodecyl sulfate gel electrophoresis are 67000 plus or minus 3000. N-Ethylmaleimide, p-chloromercuribenzoate, and dithiobis(2-nitrobenzoic acid) inhibit the enzyme. Dithiothreitol reverses the inhibition produced by the latter two reagents. The pKa of the group associated with N-ethylmaleimide inhibition is 8.6 plus or minus 0.3. A chemically competent acetyl-thioenzyme is isolable by Sephadex gel filtration. The enzymes from the brain and placenta are thus far physically and biochemically indistinguishable.

Citations

Jan 1, 1987·Molecular Neurobiology·P M Salvaterra
Jan 1, 1980·Neurochemistry International·H G Mautner
Jan 1, 1990·Brain Research Bulletin·L A CarbiniL B Hersh
Jun 1, 1997·Biochemical Pharmacology·B V Sastry
Oct 1, 1979·Journal of Chromatography·P D Dean, D H Watson
Dec 1, 1980·Proceedings of the National Academy of Sciences of the United States of America·C Cozzari, B K Hartman
May 1, 1979·Journal of Neurochemistry·B H WeberW J Driskell
Apr 1, 1978·Journal of Neurochemistry·C Brandon, J Y Wu
Apr 15, 1979·FEBS Letters·C FroissartR Massarelli
Feb 22, 2005·Protein Expression and Purification·Ae-Ri KimBrian H Shilton
Aug 15, 1984·Archives of Biochemistry and Biophysics·K Radika, D B Northrop
Oct 13, 2004·Journal of Structural Biology·Lakshmanan GovindasamyRobert McKenna
Jan 1, 1982·Scandinavian Journal of Immunology. Supplement·G Gombos, D Aunis
Feb 1, 1980·Journal of Neurochemistry·R L Ryan, W O McClure
Nov 27, 1979·Biochemistry·R L Ryan, W O McClure
Jun 1, 1977·Neurochemical Research·V K Singh, P L McGeer
Nov 1, 1977·CRC Critical Reviews in Biochemistry·H G Mautner

Related Concepts

Acetyltransferase
Caudate Nucleus Structure
Choline O-Acetyltransferase
Ethylmaleimide
Hydrogen-Ion Concentration
Tissue Specificity
Placenta
Sulfhydryl Reagents

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