Biomaterial Database

Direct chemical evidence for the mixed anhydride intermediate of carboxypeptidase A in ester and peptide hydrolysis. 1985

M E Sander, and H Witzel

Carboxypeptidase A was incubated at -60 degrees C with an excess of O-(trans-p-chlorocinnamoyl)-L-phenyllactate, O-(hippuryl)-glycolate or N-(hippuryl)-L-phenylalanine. After rapid denaturation with trichloracetic acid the precipitated protein was reduced with [3H]NaCNBH3. 3H Labeled enzyme was isolated by gel chromatography on Sephadex G-25. After complete acid hydrolysis the specific label within the protein was identified by high voltage paper electrophoresis and paper chromatography as [3H]2-amino-5-hydroxyvaleric acid, the reduction product of a gamma-acylated glutamic acid. These results give strong evidence that a mixed anhydride intermediate is formed, which for the first time was identified during the hydrolysis of classical ester as well as peptide substrates by direct chemical means.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007773	Lactates	Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
D008956	Models, Chemical	Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.	Chemical Models,Chemical Model,Model, Chemical
D010649	Phenylalanine	An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.	Endorphenyl,L-Phenylalanine,Phenylalanine, L-Isomer,L-Isomer Phenylalanine,Phenylalanine, L Isomer
D002268	Carboxypeptidases	Enzymes that act at a free C-terminus of a polypeptide to liberate a single amino acid residue.	Carboxypeptidase
D002854	Chromatography, Paper	An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).	Paper Chromatography,Chromatographies, Paper,Paper Chromatographies
D004590	Electrophoresis, Paper	Electrophoresis in which paper is used as the diffusion medium. This technique is confined almost entirely to separations of small molecules such as amino acids, peptides, and nucleotides, and relatively high voltages are nearly always used.	Paper Electrophoresis
D006016	Glycolates	Derivatives of ACETIC ACID which contain an hydroxy group attached to the methyl carbon.	2-Hydroxyacetates,Glycolate Ethers,Hydroxyacetate Ethers,Hydroxyacetates,Hydroxyacetic Acids,2 Hydroxyacetates,Acids, Hydroxyacetic,Ethers, Glycolate,Ethers, Hydroxyacetate
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities