Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells
ABSTRACT Vibrio parahaemolyticus is a globally disseminated Gram-negative marine bacterium and the leading cause of seafood-borne acute gastroenteritis. Pathogenic bacterial isolates encode two type III secretion systems (T3SS), with the second system (T3SS2) considered the main virulence factor in...
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| Format: | Article |
| Language: | English |
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American Society for Microbiology
2014-10-01
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| Series: | mBio |
| Online Access: | https://journals.asm.org/doi/10.1128/mBio.01506-14 |
| _version_ | 1818987276836798464 |
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| author | Marcela de Souza Santos Kim Orth |
| author_facet | Marcela de Souza Santos Kim Orth |
| author_sort | Marcela de Souza Santos |
| collection | DOAJ |
| description | ABSTRACT Vibrio parahaemolyticus is a globally disseminated Gram-negative marine bacterium and the leading cause of seafood-borne acute gastroenteritis. Pathogenic bacterial isolates encode two type III secretion systems (T3SS), with the second system (T3SS2) considered the main virulence factor in mammalian hosts. For many decades, V. parahaemolyticus has been studied as an exclusively extracellular bacterium. However, the recent characterization of the T3SS2 effector protein VopC has suggested that this pathogen has the ability to invade, survive, and replicate within epithelial cells. Herein, we characterize this intracellular lifestyle in detail. We show that following internalization, V. parahaemolyticus is contained in vacuoles that develop into early endosomes, which subsequently mature into late endosomes. V. parahaemolyticus then escapes into the cytoplasm prior to vacuolar fusion with lysosomes. Vacuolar acidification is an important trigger for this escape. The cytoplasm serves as the pathogen’s primary intracellular replicative niche; cytosolic replication is rapid and robust, with cells often containing over 150 bacteria by the time of cell lysis. These results show how V. parahaemolyticus successfully establishes an intracellular lifestyle that could contribute to its survival and dissemination during infection. IMPORTANCE The marine bacterium V. parahaemolyticus is the leading cause worldwide of seafood-borne acute gastroenteritis. For decades, the pathogen has been studied exclusively as an extracellular bacterium. However, recent results have revealed the pathogen’s ability to invade and replicate within host cells. The present study is the first characterization of the V. parahaemolyticus’ intracellular lifestyle. Upon internalization, V. parahaemolyticus is contained in a vacuole that would in the normal course of events ultimately fuse with a lysosome, degrading the vacuole’s contents. The bacterium subverts this pathway, escaping into the cytoplasm prior to lysosomal fusion. Once in the cytoplasm, it replicates prolifically. Our study provides new insights into the strategies used by this globally disseminated pathogen to survive and proliferate within its host. |
| first_indexed | 2024-12-20T19:04:07Z |
| format | Article |
| id | doaj.art-067e75d8efd44009883bd76f1972d512 |
| institution | Directory Open Access Journal |
| issn | 2150-7511 |
| language | English |
| last_indexed | 2024-12-20T19:04:07Z |
| publishDate | 2014-10-01 |
| publisher | American Society for Microbiology |
| record_format | Article |
| series | mBio |
| spelling | doaj.art-067e75d8efd44009883bd76f1972d5122022-12-21T19:29:18ZengAmerican Society for MicrobiologymBio2150-75112014-10-015510.1128/mBio.01506-14Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial CellsMarcela de Souza Santos0Kim Orth1Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USADepartment of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USAABSTRACT Vibrio parahaemolyticus is a globally disseminated Gram-negative marine bacterium and the leading cause of seafood-borne acute gastroenteritis. Pathogenic bacterial isolates encode two type III secretion systems (T3SS), with the second system (T3SS2) considered the main virulence factor in mammalian hosts. For many decades, V. parahaemolyticus has been studied as an exclusively extracellular bacterium. However, the recent characterization of the T3SS2 effector protein VopC has suggested that this pathogen has the ability to invade, survive, and replicate within epithelial cells. Herein, we characterize this intracellular lifestyle in detail. We show that following internalization, V. parahaemolyticus is contained in vacuoles that develop into early endosomes, which subsequently mature into late endosomes. V. parahaemolyticus then escapes into the cytoplasm prior to vacuolar fusion with lysosomes. Vacuolar acidification is an important trigger for this escape. The cytoplasm serves as the pathogen’s primary intracellular replicative niche; cytosolic replication is rapid and robust, with cells often containing over 150 bacteria by the time of cell lysis. These results show how V. parahaemolyticus successfully establishes an intracellular lifestyle that could contribute to its survival and dissemination during infection. IMPORTANCE The marine bacterium V. parahaemolyticus is the leading cause worldwide of seafood-borne acute gastroenteritis. For decades, the pathogen has been studied exclusively as an extracellular bacterium. However, recent results have revealed the pathogen’s ability to invade and replicate within host cells. The present study is the first characterization of the V. parahaemolyticus’ intracellular lifestyle. Upon internalization, V. parahaemolyticus is contained in a vacuole that would in the normal course of events ultimately fuse with a lysosome, degrading the vacuole’s contents. The bacterium subverts this pathway, escaping into the cytoplasm prior to lysosomal fusion. Once in the cytoplasm, it replicates prolifically. Our study provides new insights into the strategies used by this globally disseminated pathogen to survive and proliferate within its host.https://journals.asm.org/doi/10.1128/mBio.01506-14 |
| spellingShingle | Marcela de Souza Santos Kim Orth Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells mBio |
| title | Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells |
| title_full | Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells |
| title_fullStr | Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells |
| title_full_unstemmed | Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells |
| title_short | Intracellular <named-content content-type="genus-species">Vibrio parahaemolyticus</named-content> Escapes the Vacuole and Establishes a Replicative Niche in the Cytosol of Epithelial Cells |
| title_sort | intracellular named content content type genus species vibrio parahaemolyticus named content escapes the vacuole and establishes a replicative niche in the cytosol of epithelial cells |
| url | https://journals.asm.org/doi/10.1128/mBio.01506-14 |
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