Translational Attenuation Mechanism of ErmB Induction by Erythromycin Is Dependent on Two Leader Peptides

Shasha Wang; Kai Jiang; Xinyue Du; Yanli Lu; Lijun Liao; Zhiying He; Weizhi He

doi:10.3389/fmicb.2021.690744

Translational Attenuation Mechanism of ErmB Induction by Erythromycin Is Dependent on Two Leader Peptides

Front Microbiol. 2021 Jun 28:12:690744. doi: 10.3389/fmicb.2021.690744. eCollection 2021.

Authors

Shasha Wang^{1

2}, Kai Jiang³, Xinyue Du¹, Yanli Lu¹, Lijun Liao², Zhiying He^{1

4}, Weizhi He¹

Affiliations

¹ Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China.
² Department of Anesthesiology and Pain Management, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
³ Department of Biobank, Renji Hospital, School of Medicine, Shanghai JiaoTong University, Shanghai, China.
⁴ Shanghai Engineering Research Center of Stem Cells Translational Medicine, Shanghai, China.

Abstract

Ribosome stalling on ermBL at the tenth codon (Asp) is believed to be a major mechanism of ermB induction by erythromycin (Ery). In this study, we demonstrated that the mechanism of ermB induction by Ery depends not only on ermBL expression but also on previously unreported ermBL2 expression. Introducing premature termination codons in ermBL, we proved that translation of the N-terminal region of ermBL is the key component for ermB induced by Ery, whereas translation of the C-terminal region of ermBL did not affect Ery-induced ermB. Mutation of the tenth codon (Asp10) of ermBL with other amino acids showed that the degree of induction in vivo was not completely consistent with the data from the in vitro toe printing assay. Alanine-scanning mutagenesis of ermBL demonstrated that both N-terminal residues (R7-K11) and the latter part of ermBL (K20-K27) are critical for Ery induction of ermB. The frameshifting reporter plasmid showed that a new leader peptide, ermBL2, exists in the ermB regulatory region. Further, introducing premature termination mutation and alanine-scanning mutagenesis of ermBL2 demonstrated that the N-terminus of ermBL2 is essential for induction by Ery. Therefore, the detailed function of ermBL2 requires further study.

Keywords: erythromycin; leader peptide; ribosome stalling; translation arrest; translational attenuation.