Chlamydia trachomatis regulates growth and development in response to host cell fatty acid availability in the absence of lipid droplets.
Cell Microbiol
; 20(2)2018 02.
Article
em En
| MEDLINE
| ID: mdl-29117636
ABSTRACT
Chlamydia trachomatis (Ct) is a Gram-negative obligate intracellular pathogen of humans that causes significant morbidity from sexually transmitted and ocular diseases globally. Ct acquires host fatty acids (FA) to meet the metabolic and growth requirements of the organism. Lipid droplets (LDs) are storehouses of FAs in host cells and have been proposed to be a source of FAs for the parasitophorous vacuole, termed inclusion, in which Ct replicates. Previously, cells devoid of LDs were shown to produce reduced infectious progeny at 24 hr postinfection (hpi). Here, although we also found reduced progeny at 24 hpi, there were significantly more progeny at 48 hpi in the absence of LDs compared to the control wild-type (WT) cells. These findings were confirmed using transmission electron microscopy where cells without LDs were shown to have significantly more metabolically active reticulate bodies at 24 hpi and significantly more infectious but metabolically inert elementary bodies at 48 hpi than WT cells. Furthermore, by measuring basal oxygen consumption rates (OCR) using extracellular flux analysis, Ct infected cells without LDs had higher OCRs at 24 hpi than cells with LDs, confirming ongoing metabolic activity in the absence of LDs. Although the FA oleic acid is a major source of phospholipids for Ct and stimulates LD synthesis, treatment with oleic acid, but not other FAs, enhanced growth and led to an increase in basal OCR in both LD depleted and WT cells, indicating that FA transport to the inclusion is not affected by the loss of LDs. Our results show that Ct regulates inclusion metabolic activity and growth in response to host FA availability in the absence of LDs.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Chlamydia trachomatis
/
Crescimento e Desenvolvimento
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Interações Hospedeiro-Patógeno
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Ácidos Graxos
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Gotículas Lipídicas
Limite:
Humans
Idioma:
En
Revista:
Cell Microbiol
Assunto da revista:
MICROBIOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Estados Unidos