Premium
Evidence for a ribosome‐associated thiol protease cleaving wheat germ methionyl‐tRNA synthetase
Author(s) -
de Vencay Jacques Archambault,
Cenatiempo Yves,
Julien Raymond
Publication year - 1991
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(91)80943-w
Subject(s) - protease , proteolysis , ribosome , puromycin , biochemistry , ribonuclease , rnase p , transfer rna , ribosomal rna , ribosomal protein , chemistry , biology , enzyme , protein biosynthesis , microbiology and biotechnology , rna , gene
A wheat germ protease is responsible for M r 105000 methionyl‐tRNA synthetase hydrolysis, generating two fragments of M r 82000 (harbouring the catalytic domain) and 20000, respectively. Specificity of the protease was sought for using different kinds of protein substrates. It turned out that charged peptides were preferentially cleaved and that no proteolysis occurred when proteins were replaced by small synthetic substrates, harbouring target sites similar to those cleaved in proteins. The protease could be a ribosomal protein, since it remained associated to ribosomal structure, even after treatment by deoxycholate, Triton X‐100, 800 mM KCl and puromycin. Nevertheless, it was still active after ribonuclease treatment of the ribosomes. An identical protease activity was found in rat liver, but not in E. coli .