Staphylococcus aureus adaptation to aerobic low-redox-potential environments: implications for an intracellular lifestyle

Methicillin-resistant Staphylococcus aureus is a 'superbug' that is responsible for extensive death and morbidity. Chronic S. aureus infections are associated with the presence of intracellular bacteria and the host cytosol is an aerobic low-redox-potential (Eh) environment. How S. aureus...

Full description

Saved in:
Bibliographic Details
Published in:Microbiology (Society for General Microbiology) 2019-07, Vol.165 (7), p.779-791
Main Authors: Christmas, Benjamin A F, Rolfe, Matthew D, Rose, Matthew, Green, Jeffrey
Format: Article
Language:English
Subjects:
Adaptation, Biological
Aerobiosis
Bacterial Proteins - genetics
Bacterial Proteins - metabolism
Cytoplasm - chemistry
Cytoplasm - microbiology
Gene Expression Regulation, Bacterial
Humans
Oxidation-Reduction
Staphylococcal Infections - microbiology
Staphylococcus aureus - genetics
Staphylococcus aureus - growth & development
Staphylococcus aureus - physiology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Methicillin-resistant Staphylococcus aureus is a 'superbug' that is responsible for extensive death and morbidity. Chronic S. aureus infections are associated with the presence of intracellular bacteria and the host cytosol is an aerobic low-redox-potential (Eh) environment. How S. aureus adapts to aerobic low-Eh environments is understudied. A low external Eh, imposed by the non-metabolizable reductant dithiothreitol, resulted in transcriptional reprogramming mediated by the redox-responsive transcription factors AgrA, Rex and SrrBA, resulting in a shift towards fermentative metabolism. Accordingly, in the presence of the host cytoplasmic reductant glutathione, the aerobic respiration of S. aureus was impaired, the intracellular NADH:NAD ratio increased, lactate dehydrogenase was induced, resistance to the aminoglycoside antibiotic gentamicin was enhanced and greater numbers of small-colony variants (SCVs) were detected. These observations suggest that entry of S. aureus into the aerobic low-Eh environment of the host cytosol could result in adaptive responses that promote the formation of SCVs.
ISSN:1350-0872
1465-2080
DOI:10.1099/mic.0.000809