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Home / Equine Research Bank / Biochem J / A subunit-sized butyrylcholinesterase present in high concen...
The Biochemical journal1977; 167(2); 367-376; doi: 10.1042/bj1670367

A subunit-sized butyrylcholinesterase present in high concentrations in pooled rabbit serum.

Abstract: A butyrylcholinesterase of mol.wt. approx. 83000 was observed in pooled rabbit serum. The enzyme was named monomeric butyrylcholinesterase to distinguish it from the larger oligomeric butyrylcholinesterase of horse and human serum whose subunits are the same size as the monomeric enzyme. The active-site concentration of monomeric butyrylcholinesterase in the pooled serum was 0.18mum, which is five times the concentration of butyrylcholinesterase in pooled horse serum. This was surprising, since the horse serum is regarded as a rich source of butyrylcholinesterase, whereas rabbit serum is not generally thought to contain significant amounts of any butyrylcholinesterase. The explanation, in large part, was the relatively low k(cat.) of the monomeric enzyme, which was approx. 57s(-1) with butyrylthiocholine as substrate and is one-thirtieth of the comparable k(cat.) of horse butyrylcholinesterase. The substrate specificity of monomeric butyrylcholinesterase also differed significantly from that of horse and human butyrylcholinesterase. For example, with the monomeric enzyme, the hydrolysis of 1mm-acetylthiocholine was only 4% the rate for 1mm-butyrylthiocholine, whereas human and horse butyrylcholinesterases hydrolysed 1mm-acetylthiocholine at 50% of the rate for 1mm-butyrylthiocholine. Moreover, monomeric butyrylcholinesterase generally hydrolysed aromatic esters more rapidly than choline esters, whereas the reverse is true of the butyrylcholinesterases. To facilitate the study of monomeric butyrylcholinesterase, it was separated from the larger butyrylcholinesterase and acetylcholinesterase, also present in rabbit serum, and purified 89-fold by fractionation with (NH(4))(2)SO(4) and ion-exchange chromatography.
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Publication Date: 1977-11-01 PubMed ID: 597249PubMed Central: PMC1183667DOI: 10.1042/bj1670367Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research reveals the presence of an enzyme called butyrylcholinesterase in rabbit serum at notably higher levels than expected, with differences in function and specificity in comparison with the same enzyme found in horse and human serum.

Identification of Monomeric Butyrylcholinesterase

  • The researchers observed an enzyme named butyrylcholinesterase in pooled rabbit serum. It had a molecular weight of approx. 83000, similar to the subunits of the oligomeric structure of the same enzyme found in horse and human serum.
  • Given its singular structure, the researchers dubbed this enzyme ‘monomeric butyrylcholinesterase’ to distinguish it from larger, complex structures.

Surprising Concentration of Monomeric Butyrylcholinesterase

  • The study reports a surprising degree of active monomeric butyrylcholinesterase in the rabbit serum, at five times the concentration compared to horse serum.
  • This unconventional finding is in stark contrast to existing beliefs, where horse serum was considered a rich source of butyrylcholinesterase, while rabbit serum wasn’t perceived to encompass substantial amounts.
  • Further investigation attributed this unusual presence to the relatively low catalytic constant (kcat) of rabbit monomeric butyrylcholinesterase. Its rate was approximately 57s(-1) with butyrylthiocholine as a substrate, merely one-thirtieth of the parallel rate of horse butyrylcholinesterase.

Divergent Substrate Specificity

  • The substrate specificity of the rabbit’s monomeric butyrylcholinesterase also proved different from that of the horse and human enzymes.
  • The data revealed that the monomeric enzyme only hydrolysed 1mm-acetylthiocholine at 4% of the rate for 1mm-butyrylthiocholine, in comparison to human and horse butyrylcholinesterases, which hydrolysed it at 50% of the rate.
  • The monomeric butyrylcholinesterase also showed a preference for hydrolysing aromatic esters over choline esters, which is the opposite tendency observed in other butyrylcholinesterases.

Purification of Monomeric Butyrylcholinesterase

  • To further study the monomeric butyrylcholinesterase, it was separated and purified to an 89-fold concentration for analysis and comparison.
  • This compound was separated from the larger butyrylcholinesterase and acetylcholinesterase, also taken from rabbit serum, through a purification process involving fractionation with ammonium sulfate (NH(4))(2)SO(4) and ion-exchange chromatography.

Cite This Article

APA
Main AR, McKnelly SC, Burgess-Miller SK. (1977). A subunit-sized butyrylcholinesterase present in high concentrations in pooled rabbit serum. Biochem J, 167(2), 367-376. https://doi.org/10.1042/bj1670367

Publication

The Biochemical journal
ISSN: 0264-6021
NlmUniqueID: 2984726R
Country: England
Language: English
Volume: 167
Issue: 2
Pages: 367-376

Researcher Affiliations

Main, A R
    McKnelly, S C
      Burgess-Miller, S K

        MeSH Terms

        • Animals
        • Butyrylcholinesterase / blood
        • Cholinesterase Inhibitors
        • Cholinesterases / blood
        • Chromatography, Gel
        • Horses
        • Humans
        • Isoflurophate / pharmacology
        • Molecular Weight
        • Paraoxon / pharmacology
        • Rabbits
        • Substrate Specificity
        • Thiocholine / analogs & derivatives

        References

        This article includes 22 references
        1. Teng TL, Harpst JA, Lee JC, Zinn A, Carlson DM. Composition and molecular weights of butyrylcholinesterase from horse serum.. Arch Biochem Biophys 1976 Sep;176(1):71-81.
          pubmed: 970966doi: 10.1016/0003-9861(76)90142-9google scholar: lookup
        2. Ecobichon DJ, Comeau AM. Pseudocholinesterases of mammalian plasma: physicochemical properties and organophosphate inhibition in eleven species.. Toxicol Appl Pharmacol 1973 Jan;24(1):92-100.
          pubmed: 4631366doi: 10.1016/0041-008x(73)90184-1google scholar: lookup
        3. Lee JC, Harpst JA. Physical properties and subunit structure of butyrylcholinesterase from horse serum.. Biochemistry 1973 Apr 10;12(8):1622-30.
          pubmed: 4735538doi: 10.1021/bi00732a025google scholar: lookup
        4. Massoulié J, Rieger F. [Acetylcholinesterase of fish electric organs (torpedo and electric eel); membrane complexes].. Eur J Biochem 1969 Dec;11(3):441-55.
          pubmed: 4904700doi: 10.1111/j.1432-1033.1969.tb00794.xgoogle scholar: lookup
        5. Main AR, Tarkan E, Aull JL, Soucie WG. Purification of horse serum cholinesterase by preparative polyacrylamide gel electrophoresis.. J Biol Chem 1972 Jan 25;247(2):566-71.
          pubmed: 5009701
        6. Leuzinger W, Goldberg M, Cauvin E. Molecular properties of acetylcholinesterase.. J Mol Biol 1969 Mar 14;40(2):217-25.
          pubmed: 5365009doi: 10.1016/0022-2836(69)90470-7google scholar: lookup
        7. Das PK, Liddell J. Purification and properties of human serum cholinesterase.. Biochem J 1970 Mar;116(5):875-81.
          pubmed: 5441375doi: 10.1042/bj1160875google scholar: lookup
        8. Booth GM, Metcalf RL. Phenylthioacetate: a useful substrate for the histochemical and colorimetric detection of cholinesterase.. Science 1970 Oct 23;170(3956):455-7.
          pubmed: 5460073doi: 10.1126/science.170.3956.455google scholar: lookup
        9. Weber K, Osborn M. The reliability of molecular weight determinations by dodecyl sulfate-polyacrylamide gel electrophoresis.. J Biol Chem 1969 Aug 25;244(16):4406-12.
          pubmed: 5806584
        10. Haupt H, Heide K, Zwisler O, Schwick HG. [Isolation and physico-chemical characterization of cholinesterase in human serum].. Blut 1966 Nov;14(2):65-75.
          pubmed: 5928504doi: 10.1007/BF01633493google scholar: lookup
        11. ALDRIDGE WN. Serum esterases. I. Two types of esterase (A and B) hydrolysing p-nitrophenyl acetate, propionate and butyrate, and a method for their determination.. Biochem J 1953 Jan;53(1):110-7.
          pubmed: 13032041doi: 10.1042/bj0530110google scholar: lookup
        12. KOELLE GB. Cholinesterases of the tissues and sera of rabbits.. Biochem J 1953 Jan;53(2):217-26.
          pubmed: 13032058doi: 10.1042/bj0530217google scholar: lookup
        13. AUGUSTINSSON KB. Electrophoretic separation and classification of blood plasma esterases.. Nature 1958 Jun 28;181(4626):1786-9.
          pubmed: 13566141doi: 10.1038/1811786a0google scholar: lookup
        14. ELLMAN GL, COURTNEY KD, ANDRES V Jr, FEATHER-STONE RM. A new and rapid colorimetric determination of acetylcholinesterase activity.. Biochem Pharmacol 1961 Jul;7:88-95.
          pubmed: 13726518doi: 10.1016/0006-2952(61)90145-9google scholar: lookup
        15. MAIN AR, MILES KE, BRAID PE. The determination of human-serum-cholinesterase activity with o-nitrophenyl butyrate.. Biochem J 1961 Apr;78(4):769-76.
          pubmed: 13765461doi: 10.1042/bj0780769google scholar: lookup
        16. BERNSOHN J, BARRON KD, HESS A. Cholinesterases in serum as demonstrated by starch gel electrophoresis.. Proc Soc Exp Biol Med 1961 Oct;108:71-3.
          pubmed: 13868247doi: 10.3181/00379727-108-26848google scholar: lookup
        17. BARRNETT RJ, SELIGMAN AM. Histochemical demonstration of esterases by production of indigo.. Science 1951 Nov 30;114(2970):579-82.
          pubmed: 14901025doi: 10.1126/science.114.2970.579google scholar: lookup
        18. HOLT SJ. A new principle for the histochemical localization of hydrolytic enzymes.. Nature 1952 Feb 16;169(4294):271-3.
          pubmed: 14910747doi: 10.1038/169271a0google scholar: lookup
        19. ALDRIDGE WN. Some properties of specific cholinesterase with particular reference to the mechanism of inhibition by diethyl p-nitrophenyl thiophosphate (E 605) and analogues.. Biochem J 1950 Apr;46(4):451-60.
          pubmed: 15420172doi: 10.1042/bj0460451google scholar: lookup
        20. Sawyer CH. HYDROLYSIS OF CHOLINE ESTERS BY LIVER.. Science 1945 Apr 13;101(2624):385-6.
          pubmed: 17780326doi: 10.1126/science.101.2624.385google scholar: lookup
        21. Mendel B, Rudney H. SOME EFFECTS OF SALTS ON TRUE CHOLINESTERASE.. Science 1945 Dec 14;102(2659):616-7.
          pubmed: 17818195doi: 10.1126/science.102.2659.616google scholar: lookup
        22. Main AR, Soucie WG, Buxton IL, Arinc E. The purification of cholinesterase from horse serum.. Biochem J 1974 Dec;143(3):733-44.
          pubmed: 4462752doi: 10.1042/bj1430733google scholar: lookup

        Citations

        This article has been cited 3 times.
        1. Peng H, Brimijoin S, Hrabovska A, Krejci E, Blake TA, Johnson RC, Masson P, Lockridge O. Monoclonal antibodies to human butyrylcholinesterase reactive with butyrylcholinesterase in animal plasma. Chem Biol Interact 2016 Jan 5;243:82-90.
          doi: 10.1016/j.cbi.2015.11.011pubmed: 26585590google scholar: lookup
        2. Ralston JS, Main AR, Kilpatrick BF, Chasson AL. Use of procainamide gels in the purification of human and horse serum cholinesterases. Biochem J 1983 Apr 1;211(1):243-50.
          doi: 10.1042/bj2110243pubmed: 6870822google scholar: lookup
        3. Chatonnet A, Lorca T, Barakat A, Aron E, Jbilo O. Structure of rabbit butyrylcholinesterase gene deduced from genomic clones and from cDNA with introns. Cell Mol Neurobiol 1991 Feb;11(1):119-30.
          doi: 10.1007/BF00712804pubmed: 2013056google scholar: lookup
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