The effect of abnormal proteins on cell viability was studied using artificially cleaved polypeptides. Escherichia coli methionyl-tRNA synthetase (MetRS) consists of two distinct domains and its activity is essential for cell viability. The polypeptide chain was split by linker insertion and expressed as two fragments. Two pairs of polypeptides, one split within the N-terminal domain and another at the junction of the two domains retained aminoacylation activity. The in vitro activities of these split mutants were enhanced by the presence of chaperonin, GroESL. However, cells containing these split polypeptides became sensitive to conditions that induce GroESL. The results of this work suggest that an abnormally generated protein can cause cell death under stressful conditions.
|Number of pages||5|
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Published - 1998 Feb 4|
Bibliographical noteFunding Information:
This work was supported by Research Grant E-N96032 from the Ministry of Education. We thank Dr. Key-Sun. Kim for circular di- chroism analysis of MetRS proteins and Drs. K. Shiba, K. Musier-Forsyth, and H. S. Pai for critical comments and discussion.
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cell Biology