Identification of a substrate domain that determines system specificity in mycobacterial type VII secretion systems
Open accessAbstract
Type VII secretion (T7S) systems are specialized machineries used by mycobacterial pathogens to transport important virulence factors across their highly hydrophobic cell envelope. There are up to five mycobacterial T7S systems, named ESX-1 to ESX-5, at least three of which specifically secrete a different subset of substrates. The T7S substrates or substrate complexes are defined by the general secretion motif YxxxD/E. However this motif does not determine system specificity. Here, we show that the substrate domain recognized by the EspG chaperone is the determinant factor for this specificity. We first show that the introduction of point mutations into the EspG 1-binding domain of the ESX-1 substrate pair PE35/PPE68_1 affects their secretion. Subsequently, we demonstrate that replacing this domain by the EspG 5-binding domain of the ESX-5 substrate PPE18 resulted in EspG 5 dependence and exclusive rerouting to the ESX-5 system. This rerouting of PE35/PPE68_1 to the ESX-5 system had a negative effect on the secretion of endogenous ESX-5 substrates.
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Besides chaperone activity, these proteins are also involved in determining the secretion system specificity.
“It was suggested that besides their chaperone activity, these proteins are also involved in determining the secretion system specificity.”
From ESX/Type VII Secretion Systems—An Important Way Out for Mycobacterial Proteins (2019) · cites this paper as [49]
By substituting the binding domain of EspG, the ESX-1-dependent substrate can be rerouted to the ESX-5 system.
“Indeed, by substituting the binding domain of EspG, the ESX-1-dependent substrate can be rerouted to the ESX-5 system (49).”
From ESX/Type VII Secretion Systems—An Important Way Out for Mycobacterial Proteins (2019) · cites this paper as [49]
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- Authors
- Phan, T. H., Ummels, R., Bitter, W., & Houben, E. N. G.
- Affiliations
- Vrije Universiteit Amsterdam (NL)
- Amsterdam UMC Location Vrije Universiteit Amsterdam (NL)
- Corresponding author
- Houben, Edith N. G.
- Venue
- Scientific Reports
- Published
- 2017-02-16
- Volume
- 7
- Issue
- 1
- Pages
- 42704-42704
- ISSN
- 2045-2322 (ISSN-L)
- PMC
- PMC5311947
- OpenAlex
- W2588820084
- Cited by
- 41
- References
- 27
- Citations by year
- 2026: 3 · 2025: 2 · 2024: 4 · 2023: 3 · 2022: 4 · 2021: 4 · 2020: 5 · 2019: 9 · 2018: 6 · 2017: 1
- FWCI
- 4.42
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- Scientific Reports (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Amsterdam UMC (VU Amsterdam) - Institutional Repository (publishedVersion)
- VU Research Portal (publishedVersion, other-oa)
- Pure Amsterdam UMC (submittedVersion, other-oa)
- Data Archiving and Networked Services (DANS) (submittedVersion, other-oa)
- Data Archiving and Networked Services (DANS) (submittedVersion)
- Topics
- Health Sciences › Medicine › Infectious Diseases › Tuberculosis Research and Epidemiology
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
- Health Sciences › Medicine › Epidemiology › Mycobacterium research and diagnosis
- Keywords
- type VII secretion system, mycobacteria, ESX-1, substrate specificity, virulence factor secretion, cell envelope
- MeSH terms
- Type VII Secretion Systems, Bacterial Proteins, Microtubule-Associated Proteins, Models, Molecular, Mycobacterium, Mycobacterium tuberculosis, Protein Binding, Protein Conformation, Substrate Specificity, Protein Transport, Protein Interaction Domains and Motifs
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