Transcriptome and proteome dynamics in chemostat culture reveal how Campylobacter jejuni modulates metabolism, stress responses and virulence factors upon changes in oxygen availability.
Environ Microbiol
; 19(10): 4326-4348, 2017 10.
Article
en En
| MEDLINE
| ID: mdl-28892295
ABSTRACT
Campylobacter jejuni, the most frequent cause of food-borne bacterial gastroenteritis worldwide, is a microaerophile that has to survive high environmental oxygen tensions, adapt to oxygen limitation in the intestine and resist host oxidative attack. Here, oxygen-dependent changes in C. jejuni physiology were studied at constant growth rate using carbon (serine)-limited continuous chemostat cultures. We show that a perceived aerobiosis scale can be calibrated by the acetate excretion flux, which becomes zero when metabolism is fully aerobic (100% aerobiosis). Transcriptome changes in a downshift experiment from 150% to 40% aerobiosis revealed many novel oxygen-regulated genes and highlighted re-modelling of the electron transport chains. A label-free proteomic analysis showed that at 40% aerobiosis, many proteins involved in host colonisation (e.g., PorA, CadF, FlpA, CjkT) became more abundant. PorA abundance increased steeply below 100% aerobiosis. In contrast, several citric-acid cycle enzymes, the peptide transporter CstA, PEB1 aspartate/glutamate transporter, LutABC lactate dehydrogenase and PutA proline dehydrogenase became more abundant with increasing aerobiosis. We also observed a co-ordinated response of oxidative stress protection enzymes and Fe-S cluster biogenesis proteins above 100% aerobiosis. Our approaches reveal key virulence factors that respond to restricted oxygen availability and specific transporters and catabolic pathways activated with increasing aerobiosis.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Oxígeno
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Campylobacter jejuni
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Estrés Oxidativo
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Aerobiosis
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Año:
2017
Tipo del documento:
Article