Mimicking cotranslational folding of prosubtilisin E in vitro. (14th January 2020)

• Record Type: Journal Article
• Authors: Kim, Sung-Gun; Chen, Yu-Jen; Falzon, Liliana; Baum, Jean; Inouye, Masayori
• Is Part Of: Journal of biochemistry. Volume 167:Number 5(2020)
• Page Start: 473
• Page End: 482
• Publication Date: 2020-01-14
• Subjects: cotranslational folding intermediate -- intramolecular chaperone -- prosubtilisin E -- secondary structure; Biochemistry -- Periodicals; Biochemistry -- Periodicals; Electronic journals; 572.05
• DOI: 10.1093/jb/mvaa004
• Languages: English
• ISSNs: 0021-924X

Abstract

Abstract: Nascent polypeptides are synthesized on ribosomes starting at the N-terminus and simultaneously begin to fold during translation. We constructed N-terminal fragments of prosubtilisin E containing an intramolecular chaperone (IMC) at N-terminus to mimic cotranslational folding intermediates of prosubtilisin. The IMC-fragments of prosubtilisin exhibited progressive enhancement of their secondary structures and thermostabilities with increasing polypeptide length. However, even the largest IMC-fragment with 72 residues truncated from the C-terminus behaved as a molten globule, indicating the requirement of the C-terminal region to have a stable tertiary structure. Furthermore, truncation of the IMC in the IMC-fragments resulted in aggregation, suggesting that the IMC plays a crucial role to prevent misfolding and aggregation of cotranslational folding intermediates during translation of prosubtilisin polypeptide.