Catalysis by poly-L-lysine of aminolysis of penicillin by tris(hydroxymethyl)aminomethane.
Catalysis by poly-L-lysine of aminolysis of penicillin by tris(hydroxymethyl)aminomethane.
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聚-L-赖氨酸催化三(羟甲基)氨基甲烷氨解青霉素。
DOI：
10.1021/jm00301a009
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发表时间：
1969
影响因子：
7.3
通讯作者：
M. Schwartz
中科院分区：
文献类型：
--
作者：
M. Schwartz
The rate of penicillin loss in solutions containing both poly-L-lysine (PLL) and Tris in the pH range 7-9 is much more rapid than with either Tris or PLL alone. The rate is directly proportional to PLL concentration at low concentrations of PLL but becomes independent of Tris at high concentrations of the latter. Evidence is presented to show that the reactiontaking place is aminolysis ofpenicillin by Tris catalyzed by PLL. Based on these results a mechanism is proposed which involves complex formation between PLL and penicillin prior in attack by Tris. This reaction may be a model for aminolysis of penicillin in vivo, leading to formation of antigen involved in penicillin allergy.The principal antigenic determinant in penicillin allergy is the penicilloyl group bound by amide linkage to e-amino groups of lysine residues on proteins. 1 One pathway by which formation of this hapten-protein conjugate may occur is the direct aminolysis of penicillin by the amino group. 2'3 Investigation of the mechanism ofthis reaction in a model system, using glycine its the amine, revealed that general base catalysis by a second molecule of glycine anion is required. 4 Further study of the reaction of benzylpenicillin with diamines suggested that intramolecular general base catalysis by one of the amino groups was involved and could increase reaction rate. 5 The present work was initiated to study the reaction of benzylpenicillin with poly-L-lysine (I’LL), where it was thought that the large number of amino groups on the same molecule would accelerate the rate and perhaps be a better model for in vivo conditions.
