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Expression, Purification, and Liposome Binding of Budding Yeast SNX-BAR Heterodimers
Published on: December 6, 2019
Archaeosortases and exosortases are widely distributed systems linking membrane transit with posttranslational
Daniel H Haft1, Samuel H Payne, Jeremy D Selengut
1J Craig Venter Institute, Rockville, Maryland, USA. haft@jcvi.org
Journal of Bacteriology
|November 1, 2011
Summary
New prokaryotic protein-sorting signals, including PGF-CTERM in archaea, were identified. These signals, processed by exosortase enzymes like archaeosortase A, are crucial for protein transport and modification.
Area of Science:
- Microbiology
- Biochemistry
- Genomics
Background:
- Prokaryotic protein secretion relies on C-terminal sorting signals.
- Existing signals like LPXTG and PEP-CTERM share a tripartite architecture.
- The diversity and function of these signals across archaea and bacteria are not fully understood.
Purpose of the Study:
- To identify and characterize novel prokaryotic C-terminal protein-sorting signals.
- To investigate the evolutionary relationships and enzymatic processing of these signals.
- To understand the role of these systems in protein transport and post-translational modification.
Main Methods:
- Comparative genomics to identify conserved protein domains and gene neighborhoods.
- Construction of hidden Markov models for novel signal motifs.
- Proteomics to confirm signal processing and protein modification.
Main Results:
- Discovery of multiple new C-terminal protein-sorting signals, including PGF-CTERM, VPXXXP-CTERM, and PEF-CTERM.
- Identification of archaeosortase A (ArtA) as the processing enzyme for PGF-CTERM.
- Characterization of diverse bacterial exosortase systems (C, D, E) and related families (XrtF, XrtG).
Conclusions:
- A well-differentiated superfamily of membrane-embedded protein-processing enzymes (exosortases) has evolved.
- These systems are ancient and play a critical role in protein trafficking and post-translational modifications like glycosylation.
- The findings reveal significant diversity in prokaryotic protein-sorting mechanisms across archaea and bacteria.
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