Binding of transcriptional activators to sigma 54 in the presence of the transition state analog ADP-aluminum fluoride: insights into activator mechanochemical action.
Conformational changes in sigma 54 (sigma(54)) and sigma(54)-holoenzyme depend on nucleotide hydrolysis by an activator. We now show that sigma(54) and its holoenzyme bind to the central ATP-hydrolyzing domains of the transcriptional activators PspF and NifA in the presence of ADP-aluminum fluoride, an analog of ATP in the transition state for hydrolysis. Direct binding of sigma(54) Region I to activator in the presence of ADP-aluminum fluoride was shown and inferred from in vivo suppression genetics. Energy transduction appears to occur through activator contacts to sigma(54) Region I. ADP-aluminum fluoride-dependent interactions and consideration of other AAA+ proteins provide insight into activator mechanochemical action.
Chaney
M
M
Department of Biology and Biochemistry, Faculty of Life Sciences, Sir Alexander Fleming Building, Imperial College of Science Technology and Medicine, London SW7 2AZ, UK.
Grande
R
R
Wigneshweraraj
S R
SR
Cannon
W
W
Casaz
P
P
Gallegos
M T
MT
Schumacher
J
J
Jones
S
S
Elderkin
S
S
Dago
A E
AE
Morett
E
E
Buck
M
M
D000244:Adenosine Diphosphate / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D017607:Aluminum Compounds / Q000378:metabolism / Q000494:pharmacology*; D001483:Base Sequence; D020134:Catalytic Domain; D004268:DNA-Binding Proteins; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D003850:Deoxyribonuclease I / Q000378:metabolism; D005459:Fluorides / Q000378:metabolism / Q000494:pharmacology*; D006868:Hydrolysis; D007711:Klebsiella pneumoniae / Q000378:metabolism; D009154:Mutation; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D051877:RNA Polymerase Sigma 54; D012808:Sigma Factor / Q000378:metabolism*; D016962:Sinorhizobium meliloti / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D001616:beta-Galactosidase / Q000378:metabolism
D017607:Aluminum Compounds; D004268:DNA-Binding Proteins; D012808:Sigma Factor; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54; D003850:Deoxyribonuclease I; D001616:beta-Galactosidase; D005459:Fluorides; C032311:aluminum fluoride