ATPase activity of TyrR, a transcriptional regulatory protein for sigma 70 RNA polymerase.
The TyrR protein of Escherichia coli is the chief transcriptional regulator of several genes essential for aromatic amino acid biosynthesis and transport. It was established in previous studies that this protein binds ATP, that the TyrR.ATP complex has enhanced affinity for tyrosine, and that the susceptibility of the TyrR protein to hydrolysis by trypsin is altered by ATP. Here we show that the TyrR protein has ATPase activity, which is stimulated by tyrosine. In this respect the TyrR protein resembles the transcriptional activator NtrC. The NtrC protein contains an internal polypeptide segment, 220 amino acid residues in length, with a high degree of identity to the TyrR protein, that contains the presumptive ATPase catalytic center.
Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907.
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D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D002384:Catalysis; D002852:Chromatography, Ion Exchange; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D029968:Escherichia coli Proteins; D006868:Hydrolysis; D012097:Repressor Proteins / Q000302:isolation & purification / Q000378:metabolism*; D012808:Sigma Factor / Q000378:metabolism; D014158:Transcription, Genetic; D014443:Tyrosine / Q000378:metabolism
D029968:Escherichia coli Proteins; D012097:Repressor Proteins; D012808:Sigma Factor; C069256:TyrR protein, E coli; D014443:Tyrosine; D000255:Adenosine Triphosphate; C081775:RNA polymerase sigma 70; D012321:DNA-Directed RNA Polymerases; D000251:Adenosine Triphosphatases