Acyl-Acyl carrier protein regulates transcription of fatty acid biosynthetic genes via the FabT repressor in Streptococcus pneumoniae.
Long-chain acyl-acyl carrier proteins (acyl-ACP) are established biochemical regulators of bacterial type II fatty acid synthases due to their ability to feedback-inhibit the early steps in the biosynthetic pathway. In Streptococcus pneumoniae, the expression of the fatty acid synthase (fab) genes is controlled by a helix-turn-helix transcriptional repressor called FabT. A screen of pathway intermediates identified acyl-ACP as a ligand that increased the affinity of FabT for DNA. FabT bound to a wide range of acyl-ACP chain lengths in the absence of DNA, but only the long-chain acyl-ACPs increase the affinity of FabT for DNA. FabT affinity for DNA increased with increasing acyl-ACP chain length with cis-vaccenoyl-ACP being the most effective ligand. Thus, FabT is a new ACP-interacting partner that acts as a transcriptional rheostat to fine tune the expression of the fab genes based on the demand for fatty acids.
Jerga
Agoston
A
From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
Rock
Charles O
CO
D000213:Acyl Carrier Protein / Q000235:genetics / Q000378:metabolism*; D002850:Chromatography, Gel; D017931:DNA Primers; D015342:DNA Probes; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D054889:Fatty Acid Synthase, Type II / Q000235:genetics*; D005227:Fatty Acids / Q000096:biosynthesis / Q000235:genetics*; D019077:Helix-Turn-Helix Motifs / Q000235:genetics; D007700:Kinetics; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism; D013296:Streptococcus pneumoniae / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
D000213:Acyl Carrier Protein; D017931:DNA Primers; D015342:DNA Probes; D004269:DNA, Bacterial; D005227:Fatty Acids; D012097:Repressor Proteins; D054889:Fatty Acid Synthase, Type II