Sequestration of host metabolism by an intracellular pathogen
Abstract
For intracellular pathogens, residence in a vacuole provides a shelter against cytosolic host defense to the cost of limited access to nutrients. The human pathogen Chlamydia trachomatis grows in a glycogen-rich vacuole. How this large polymer accumulates there is unknown. We reveal that host glycogen stores shift to the vacuole through two pathways: bulk uptake from the cytoplasmic pool, and de novo synthesis. We provide evidence that bacterial glycogen metabolism enzymes are secreted into the vacuole lumen through type 3 secretion. Our data bring strong support to the following scenario: bacteria co-opt the host transporter SLC35D2 to import UDP-glucose into the vacuole, where it serves as substrate for de novo glycogen synthesis, through a remarkable adaptation of the bacterial glycogen synthase. Based on these findings we propose that parasitophorous vacuoles not only offer protection but also provide a microorganism-controlled metabolically active compartment essential for redirecting host resources to the pathogens.
Article and author information
Author details
Reviewing Editor
- Dominique Soldati-Favre, University of Geneva, Switzerland
Version history
- Received: October 28, 2015
- Accepted: March 15, 2016
- Accepted Manuscript published: March 16, 2016 (version 1)
- Version of Record published: April 8, 2016 (version 2)
Copyright
© 2016, Gehre et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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