Benzoylarginine ethyl ester

G. Fleck and S. J. Singer, unpublished experiments. Enzymatic activity was measured by the rate of alkali consumption by the hydrolysis of benzoylarginine ethyl ester at pH 8 in a phosphate-NaCl buffer (Inagami and Sturtevant, 1960). 

The activity of trypsin is determined by comparing the rate at which it hydrolyzes benzoylarginine ethyl ester hydrochloride R with the rate at which trypsin BRP hydrolyzes the same substrate in the same conditions. 

Store the solutions at 0-5°C. Warm 1 mL of each solution to about 25°C over 15 min and use 50 xL of each solution for each titration. Carry out the titration in an atmosphere of nitrogen. Transfer 10.0 mL of borate buffer solution pH 8.0 (0.0015 M) R to the reaction vessel and, while stirring, add 1.0 mL, of a freshly prepared 0.686% m/V solution of benzoylarginine ethyl ester hydrochloride R. 

Benzoylarginine Ethyl Ester Hydrochloride [C15H23CIN4O3 (Mr 342.8) AA-benzoyl-L-arginine ethyl ester hydrochloride ethyl (S)-2-benzamido-5-guanidinovalerate hydrochloride]... 

The ferrocene 44 bearing only one tetrapeptide chain (-Gly-Gly-L-Tyr-L-Arg-OH) is designed to bind to papain [147]. The ferrocene 44 acts as an efficient competitive papain inhibitor for AT-benzoylarginine ethyl ester hydrolysis, with an inhibition constant Ki of 9 xM at pH 6.2. Binding of papain to the ferrocene receptor 44 causes an electrochemical response, resulting in a small cathodic shift of the redox potential of the ferrocene moiety of 44. 

Limited experimental data for liquid-soUd mass transfer are available. Oliver and Hoon [47] measured heat transfer in two-phase flow in capillaries using very viscous liquids and hence with thick lubricating layers. The best data set is by Horvath et al. [48], who measured the hydrolysis of N-benzoylarginine ethyl ester in a 1.2 m long tube coated with the immobilized enzyme trypsin. The intrinsic rate of this reaction was high enough that mass transfer from the liquid was limiting. The experimental data are reported as Sh versus Is/dh with the Reynolds number Re as a parameter and Sh versus Re with the aspect ratio Is/dh as a parameter. 

Trypsin, chymotrypsin, and carboxypeptidase, long thought to be specific only for the hydrolysis of peptide bonds also display a specific esterase activity. 2 Trypsin, for example, splits ammonia from benzoylargininamide and as well splits ethanol from benzoylarginine ethyl ester. No activity, however, is shown toward ethyl butyrate, a substrate for an aliphatic esterase. 

The copolymei(L-Cys, L-Glu) hydrolyzed benzoylarginine derivatives(ethyl ester and amides, 19) with an optimum pH of 6.1 and optimum temperature of 40 C. This pH value corre onds to one of the two optimum pH in the hydrolysis of PNPA. The urease activity was also noted for this copolymer, and increased witii air oxidation of some SH groups (i2<5). 

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