The Kinetics of the Pepsin-Catalyzed Hydrolysis of N-Carbobenzoxy-L-Glutamyl-L-Tyrosine by Determination of the Spectrophotometer

合成基質 N-Carbobenzoxy-L-glutamyl-L-tyrosine의 Pepsin 加水分解反應의 分光光度法에 依한 速度論的 硏究

  • Hong Dae Shin (Department of Chemistry, Pusan National University)
  • Published : 19700600

Abstract

The kinetics of the pepsin-catalyzed hydrolysis of N-carbobenzoxy-L-glutamyl-L-tyrosine at pH 3.5 and $37^{\circ}C$ were determined by a spectrophotometric technique. The pepsin used was further purified on a Sephadex G-75 column. The kinetics data were Km = l.7 ${\times}10^{-3}M,\;-{\Delta}F^{\circ}$ = 3.99Kcal/mole, and $k^3=\;2.1{\times}10^{-2}\;sec^{-1}$. An analysis of the above data and other investigators' data obtained from some dipeptides led to the following conclusions. (1) Phenylalanyl residues in a synthetic peptide are bound to pepsin more strongly than glutamyl or tyrosyl residues, supporting the theory that a part of the binding region of the active center is hydrophobic. (2) Dipeptides are bound to pepsin principally through their side chains and the binding involves both side-chain residues. (3) The nature of amino acids in dipeptides $R_2-R_1,\;affect\;the\;k_3$ values.

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References

  1. J. Am. Chem. Soc. v.72 Casey, E.L.;Laidier, K.J.
  2. J. Biol. Chem. v.193 Baker, L.E.
  3. J. Biol. Chem. v.211 Baker, L.E.
  4. Nature v.178 Green, N.M.
  5. Enzymes v.4 Dovey, F.A.;Yanari, S.S.
  6. Gen. Physiol. v.45 Herriott, R.M.
  7. J. Am. Chem. Soc. v.88 Zeffren, E.;Kaiser, E.T.
  8. Biochemistry v.5 Inouye, K.;Veynick, I.M.;Delpierre, G.R.;Fruton, J.S.
  9. Nature v.199 Tang, J.
  10. J. Biol. Chem. v.241 Rajagopalan, T.G.;Moore, S.;Stein, W.H.
  11. J. Biol. Chem. v.176 Moore, S.;Stein, W.H.
  12. J. Am. Chem. Soc. v.56 Lineweaver, H.;Burk, D.
  13. J. Am. Chem. Soc. v.87 Silver, M.;S Denburg;T.L.;Steffins, J.J.
  14. Biochemistry v.4 Jackson, W.T.;Schlamowitz, M.;Shaw, A.
  15. J. Biol. Chem. v.240 Tang, J.