Genetic code expansion enables visualization of Salmonella type three secretion system components and secreted effectors

Moirangthem Kiran Singh, Parisa Zangoui, Yuki Yamanaka, Linda J. Kenney

Research output: Contribution to journalArticlepeer-review

Abstract

Type three secretion systems enable bacterial pathogens to inject effectors into the cytosol of eukaryotic hosts to reprogram cellular functions. It is technically challenging to label effectors and the secretion machinery without disrupting their structure/function. Herein, we present a new approach for labeling and visualization of previously intractable targets. Using genetic code expansion, we site-specifically labeled SsaP, the substrate specificity switch, and SifA, a here-to-fore unlabeled secreted effector. SsaP was secreted at later infection times; SsaP labeling demonstrated the stochasticity of injectisome and effector expression. SifA was labeled after secretion into host cells via fluorescent unnatural amino acids or non-fluorescent labels and a subsequent click reaction. We demonstrate the superiority of imaging after genetic code expansion compared to small molecule tags. It provides an alternative for labeling proteins that do not tolerate N-or C-terminal tags or fluorophores and thus is widely applicable to other secreted effectors and small proteins.

Original languageEnglish (US)
Article numbere67789
JournaleLife
Volume10
DOIs
StatePublished - Jun 2021

ASJC Scopus subject areas

  • Neuroscience(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)

Fingerprint

Dive into the research topics of 'Genetic code expansion enables visualization of Salmonella type three secretion system components and secreted effectors'. Together they form a unique fingerprint.

Cite this