Isolated epsilon subunit of Bacillus subtilis F1-ATPase binds ATP.
Previously, we demonstrated ATP binding to the isolated epsilon subunit of F1-ATPase from thermophilic Bacillus PS3 [Kato-Yamada Y., Yoshida M. (2003) J. Biol. Chem. 278, 36013]. However, whether it is a general feature of the epsilon subunit from other sources is yet unclear. Here, using a sensitive method to detect weak interactions between fluorescently labeled epsilon subunit and nucleotide, it was shown that the epsilon subunit of F1-ATPase from Bacillus subtilis also bound ATP. The dissociation constant for ATP binding at room temperature was calculated to be 2 mM, which may be suitable for sensing cellular ATP concentration in vivo.
Kato-Yamada
Yasuyuki
Y
Department of Life Sciences and Frontier Project Life's Adaptation Strategies to Environmental Changes, College of Science, Rikkyo (St. Paul's) University, 3-34-1, Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan. katoyama@rikkyo.ac.jp
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology*; D007700:Kinetics; D009154:Mutation; D010957:Plasmids; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006180:Proton-Translocating ATPases / Q000737:chemistry*; D017186:Titrimetry
D021122:Protein Subunits; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases