New Perspectives on Escherichia coli Signal Peptidase I Substrate Specificity: Investigating Why the TasA Cleavage Site Is Incompatible with LepB Cleavage.

ABSTRACT: Escherichia coli signal peptidase I (LepB) has been shown to inefficiently cleave secreted proteins with aromatic amino acids at the second position after the signal peptidase cleavage site (P2'). The Bacillus subtilis exported protein TasA contains a phenylalanine at P2', which in B. subtilis is cleaved by a dedicated archaeal-organism-like signal peptidase, SipW. We have previously shown that when the TasA signal peptide is fused to maltose binding protein (MBP) up to the P2' position, the TasA-MBP fusion protein is cleaved very inefficiently by LepB. However, the precise reason why the TasA signal peptide hinders cleavage by LepB is not known. In this study, a set of 11 peptides were designed to mimic the inefficiently cleaved secreted proteins, wild-type TasA and TasA-MBP fusions, to d

SUBMITTER: Musik JE 

PROVIDER: S-EPMC10269814 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature