Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector
ABSTRACT Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is one of the most successful human pathogens. One reason for its success is that Mtb can reside within host macrophages, a cell type that normally functions to phagocytose and destroy infectious bacteria. However, Mtb i...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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American Society for Microbiology
2019-06-01
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| Series: | mSphere |
| Subjects: | |
| Online Access: | https://journals.asm.org/doi/10.1128/mSphere.00354-19 |
| _version_ | 1818916946796609536 |
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| author | Chelsea E. Stamm Breanna L. Pasko Sujittra Chaisavaneeyakorn Luis H. Franco Vidhya R. Nair Bethany A. Weigele Neal M. Alto Michael U. Shiloh |
| author_facet | Chelsea E. Stamm Breanna L. Pasko Sujittra Chaisavaneeyakorn Luis H. Franco Vidhya R. Nair Bethany A. Weigele Neal M. Alto Michael U. Shiloh |
| author_sort | Chelsea E. Stamm |
| collection | DOAJ |
| description | ABSTRACT Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is one of the most successful human pathogens. One reason for its success is that Mtb can reside within host macrophages, a cell type that normally functions to phagocytose and destroy infectious bacteria. However, Mtb is able to evade macrophage defenses in order to survive for prolonged periods of time. Many intracellular pathogens secrete virulence factors targeting host membranes and organelles to remodel their intracellular environmental niche. We hypothesized that Mtb secreted proteins that target host membranes are vital for Mtb to adapt to and manipulate the host environment for survival. Thus, we characterized 200 secreted proteins from Mtb for their ability to associate with eukaryotic membranes using a unique temperature-sensitive yeast screen and to manipulate host trafficking pathways using a modified inducible secretion screen. We identified five Mtb secreted proteins that both associated with eukaryotic membranes and altered the host secretory pathway. One of these secreted proteins, Mpt64, localized to the endoplasmic reticulum during Mtb infection of murine and human macrophages and impaired the unfolded protein response in macrophages. These data highlight the importance of secreted proteins in Mtb pathogenesis and provide a basis for further investigation into their molecular mechanisms. IMPORTANCE Advances have been made to identify secreted proteins of Mycobacterium tuberculosis during animal infections. These data, combined with transposon screens identifying genes important for M. tuberculosis virulence, have generated a vast resource of potential M. tuberculosis virulence proteins. However, the function of many of these proteins in M. tuberculosis pathogenesis remains elusive. We have integrated three cell biological screens to characterize nearly 200 M. tuberculosis secreted proteins for eukaryotic membrane binding, host subcellular localization, and interactions with host vesicular trafficking. In addition, we observed the localization of one secreted protein, Mpt64, to the endoplasmic reticulum (ER) during M. tuberculosis infection of macrophages. Interestingly, although Mpt64 is exported by the Sec pathway, its delivery into host cells was dependent upon the action of the type VII secretion system. Finally, we observed that Mpt64 impairs the ER-mediated unfolded protein response in macrophages. |
| first_indexed | 2024-12-20T00:26:15Z |
| format | Article |
| id | doaj.art-159f05ea47384c9c90842d3b47c3a1cf |
| institution | Directory Open Access Journal |
| issn | 2379-5042 |
| language | English |
| last_indexed | 2024-12-20T00:26:15Z |
| publishDate | 2019-06-01 |
| publisher | American Society for Microbiology |
| record_format | Article |
| series | mSphere |
| spelling | doaj.art-159f05ea47384c9c90842d3b47c3a1cf2022-12-21T20:00:03ZengAmerican Society for MicrobiologymSphere2379-50422019-06-014310.1128/mSphere.00354-19Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial EffectorChelsea E. Stamm0Breanna L. Pasko1Sujittra Chaisavaneeyakorn2Luis H. Franco3Vidhya R. Nair4Bethany A. Weigele5Neal M. Alto6Michael U. Shiloh7Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USAABSTRACT Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is one of the most successful human pathogens. One reason for its success is that Mtb can reside within host macrophages, a cell type that normally functions to phagocytose and destroy infectious bacteria. However, Mtb is able to evade macrophage defenses in order to survive for prolonged periods of time. Many intracellular pathogens secrete virulence factors targeting host membranes and organelles to remodel their intracellular environmental niche. We hypothesized that Mtb secreted proteins that target host membranes are vital for Mtb to adapt to and manipulate the host environment for survival. Thus, we characterized 200 secreted proteins from Mtb for their ability to associate with eukaryotic membranes using a unique temperature-sensitive yeast screen and to manipulate host trafficking pathways using a modified inducible secretion screen. We identified five Mtb secreted proteins that both associated with eukaryotic membranes and altered the host secretory pathway. One of these secreted proteins, Mpt64, localized to the endoplasmic reticulum during Mtb infection of murine and human macrophages and impaired the unfolded protein response in macrophages. These data highlight the importance of secreted proteins in Mtb pathogenesis and provide a basis for further investigation into their molecular mechanisms. IMPORTANCE Advances have been made to identify secreted proteins of Mycobacterium tuberculosis during animal infections. These data, combined with transposon screens identifying genes important for M. tuberculosis virulence, have generated a vast resource of potential M. tuberculosis virulence proteins. However, the function of many of these proteins in M. tuberculosis pathogenesis remains elusive. We have integrated three cell biological screens to characterize nearly 200 M. tuberculosis secreted proteins for eukaryotic membrane binding, host subcellular localization, and interactions with host vesicular trafficking. In addition, we observed the localization of one secreted protein, Mpt64, to the endoplasmic reticulum (ER) during M. tuberculosis infection of macrophages. Interestingly, although Mpt64 is exported by the Sec pathway, its delivery into host cells was dependent upon the action of the type VII secretion system. Finally, we observed that Mpt64 impairs the ER-mediated unfolded protein response in macrophages.https://journals.asm.org/doi/10.1128/mSphere.00354-19Mycobacterium tuberculosiseffector functionspathogenesis |
| spellingShingle | Chelsea E. Stamm Breanna L. Pasko Sujittra Chaisavaneeyakorn Luis H. Franco Vidhya R. Nair Bethany A. Weigele Neal M. Alto Michael U. Shiloh Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector mSphere Mycobacterium tuberculosis effector functions pathogenesis |
| title | Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector |
| title_full | Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector |
| title_fullStr | Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector |
| title_full_unstemmed | Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector |
| title_short | Screening <named-content content-type="genus-species">Mycobacterium tuberculosis</named-content> Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector |
| title_sort | screening named content content type genus species mycobacterium tuberculosis named content secreted proteins identifies mpt64 as a eukaryotic membrane binding bacterial effector |
| topic | Mycobacterium tuberculosis effector functions pathogenesis |
| url | https://journals.asm.org/doi/10.1128/mSphere.00354-19 |
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