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.
From the Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
Agoston
A
Jerga
Charles O
CO
Rock
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