The trypsin-catalyzed activation of glutamate dehydrogenase purified from eel liver.
Eel liver glutamate dehydrogenase (GDH) [EC 1.4.1.3] was eightfold activated by trypsin and the molecular weight of the subunit of the native GDH decreased from 54,000 to 50,000. The C-terminal amino acid of both subunits was Thr. One peptide was released after proteolysis of the native GDH by trypsin and purified by anhydrotrypsin agarose and reversed-phase HPLC. The isolated peptide consisted of 39 amino acids and its amino acid sequence was as follows: H2NS-E-A-V-E-K-E-D-D-P-N-F-F-K-M-V-E-G-F-F-D-K-G-A-A-I- V-E-N-K-L-V-E-E-D-L-K-T-R-COOH. The peptide contained the N-terminal of the native GDH and its molecular weight was calculated to be 4,413. We concluded that the trypsin-catalyzed activation was caused by release of this peptide from the native GDH. p-Chloromercuribenzoic acid inhibited the activity of the trypsin-treated GDH, but stimulated that of the native GDH. The response of trypsin-treated GDH to ADP and GTP was decreased compared with that of the native GDH.
Tang
M Q
MQ
Laboratory of Food Chemistry, Faculty of Fisheries, Kagoshima University.
Ando
S
S
Yamada
S
S
Hayashi
S
S
D000595:Amino Acid Sequence; D000818:Animals; D002729:Chloromercuribenzoates / Q000494:pharmacology; D004524:Eels / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D005969:Glutamate Dehydrogenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009711:Nucleotides / Q000494:pharmacology; D010455:Peptides / Q000737:chemistry / Q000235:genetics; D011487:Protein Conformation; D014357:Trypsin / Q000494:pharmacology; D020245:p-Chloromercuribenzoic Acid
D002729:Chloromercuribenzoates; D009711:Nucleotides; D010455:Peptides; D020245:p-Chloromercuribenzoic Acid; D005969:Glutamate Dehydrogenase; D014357:Trypsin