Symposium Articles
Esterase-Like Activity of Human Serum Albumin II: Reaction with N-trans-Cinnamoylimidazoles

https://doi.org/10.1002/jps.2600720416Get rights and content

Abstract

□ To elucidate the details of the esterase activity of human serum albumin, the reaction of N-trans-cinnamoylimidazoles with albumin was investigated kinetically at various pHs at 25°. The reaction consisted of the acylation of albumin (probably the tyrosine-411 residue) by the substrate and the deacylation of cinnamoyl-albumin. The acylation was ~10-100-fold faster than the spontaneous hydrolysis of the substrate over the pH range examined. The pH profile for the deacylation rate constant indicated the participation of a group having a pICi of ~9.4. The deacylation was subjected to the effect of deuterium oxide. The electron-withdrawing substituent facilitated the deacylation; the Hammett p value was 1.63. These results suggest that the deacylation proceeded via general base catalysis by this group.

REFERENCES (22)

  • J.J. Vallner

    J. Pharm. Sci.

    (1977)
  • K.J. Fehske et al.

    Biochem. Pharmacol.

    (1981)
  • G.E. Means et al.

    Arch. Biochem. Biophys.

    (1979)
  • K.J. Fehske et al.

    Arch. Biochem. Biophys.

    (1980)
  • R.F. Chen

    J. Biol. Chem.

    (1967)
  • G.R. Schonbaum et al.

    ibid

    (1961)
  • J.W. Amshey et al.

    Arch. Biochem. Biophys.

    (1975)
  • Y. Kurono et al.

    Chem. Pharm. Bull. Part I

    (1979)
  • G.E. Means et al.

    Biochemistry

    (1975)
  • Y. Ozeki et al.

    Chem. Pharm. Bull.

    (1980)
  • Y. Kurono et al.

    ibid

    (1981)
  • Cited by (36)

    • Molecular and practical aspects of the enzymatic properties of human serum albumin and of albumin-ligand complexes

      2013, Biochimica et Biophysica Acta - General Subjects
      Citation Excerpt :

      This step is followed by a slower and rate limiting one in which the acylated protein is deacylated by general acid or base catalysis with the participation of water. Principally the same mechanism was proposed by Ohta et al. [13], who examined the HSA catalyzed hydrolysis of a series of N-trans-cinnamoylimidazoles (amides) and by Kurono et al. [14], who studied the hydrolysis of ten amino acid p-nitrophenyl esters. The latter authors also found that making the esters more hydrophobic by incorporating an N-carbobenzoxy group accelerated the enzymatic activity of HSA; N-carbobenzoxy-d-alanine p-nitrophenyl ester was the best substrate studied.

    • Esterase activity in rat hepatocytes

      1991, Biochemical Pharmacology
    View all citing articles on Scopus
    View full text