MalT, the regulatory protein of the Escherichia coli maltose system, is an ATP-dependent transcriptional activator.
We show that MalT, the transcriptional activator of the Escherichia coli maltose regulon, specifically binds ATP and dATP with a high affinity (Kd = 0.4 microM) and exhibits a weak ATPase activity. Using an abortive initiation assay, we further show that activation of open complex formation by MalT depends on the presence of ATP in addition to that of maltotriose, the inducer of the maltose system. Similar experiments in which ATP was replaced by ADP or AMP-PNP, a non-hydrolysable analogue of ATP, demonstrate that this reaction does not require ATP hydrolysis. As revealed by DNase I footprinting, both ATP and maltotriose are required for the binding of the MalT protein to the mal promoter DNA.
Richet
E
E
Unité de Génétique Moléculaire, Institut Pasteur, Paris, France.
Raibaud
O
O
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins; D003838:Deoxyadenine Nucleotides / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006868:Hydrolysis; D008320:Maltose / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D003838:Deoxyadenine Nucleotides; D029968:Escherichia coli Proteins; C058976:MalT protein, E coli; D014157:Transcription Factors; D008320:Maltose; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C026600:2'-deoxyadenosine triphosphate