Incorporation of extracellular fatty acids by a fatty acid kinase-dependent pathway in Staphylococcus aureus.
Mol Microbiol
; 92(2): 234-45, 2014 Apr.
Article
in En
| MEDLINE
| ID: mdl-24673884
ABSTRACT
Acyl-CoA and acyl-acyl carrier protein (ACP) synthetases activate exogenous fatty acids for incorporation into phospholipids in Gram-negative bacteria. However, Gram-positive bacteria utilize an acyltransferase pathway for the biogenesis of phosphatidic acid that begins with the acylation of sn-glycerol-3-phosphate by PlsY using an acyl-phosphate (acyl-PO4 ) intermediate. PlsX generates acyl-PO4 from the acyl-ACP end-products of fatty acid synthesis. The plsX gene of Staphylococcus aureus was inactivated and the resulting strain was both a fatty acid auxotroph and required de novo fatty acid synthesis for growth. Exogenous fatty acids were only incorporated into the 1-position and endogenous acyl groups were channeled into the 2-position of the phospholipids in strain PDJ39 (ΔplsX). Extracellular fatty acids were not elongated. Removal of the exogenous fatty acid supplement led to the rapid accumulation of intracellular acyl-ACP and the abrupt cessation of fatty acid synthesis. Extracts from the ΔplsX strain exhibited an ATP-dependent fatty acid kinase activity, and the acyl-PO4 was converted to acyl-ACP when purified PlsX is added. These data reveal the existence of a novel fatty acid kinase pathway for the incorporation of exogenous fatty acids into S. aureus phospholipids.
Full text:
1
Database:
MEDLINE
Main subject:
Phosphotransferases
/
Staphylococcus aureus
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Bacterial Proteins
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Metabolic Networks and Pathways
/
Fatty Acids
Language:
En
Journal:
Mol Microbiol
Year:
2014
Type:
Article
Affiliation country:
United States