Nucleotide binding states of subunit A of the A-ATP synthase and the implication of P-loop switch in evolution.Kumar, A., Manimekalai, M.S., Balakrishna, A.M., Jeyakanthan, J., Gruber, G.
(2010) J.Mol.Biol. 396: 301-320
- PubMed: 19944110
- DOI: 10.1016/j.jmb.2009.11.046
- Primary Citation of Related Structures:
- Also Cited By: 3SE0, 3SDZ, 3QJY, 3QIA, 3QG1, 3P20, 3ND9, 3ND8, 3MFY, 3M4Y
- PubMed Abstract:
- Structure of the catalytic nucleotide-binding subunit A of A-type ATP synthase from Pyrococcus horikoshii reveals a novel domain related to the peripheral stalk.
Maegawa, Y.,Morita, H.,Iyaguchi, D.,Yao, M.,Watanabe, N.,Tanaka, I.
(2006) Acta Crystallogr.,Sect.D 62: 483
The crystal structures of the nucleotide-empty (A(E)), 5'-adenylyl-beta,gamma-imidodiphosphate (A(PNP))-bound, and ADP (A(DP))-bound forms of the catalytic A subunit of the energy producer A(1)A(O) ATP synthase from Pyrococcus horikoshii OT3 have bee ...
The crystal structures of the nucleotide-empty (A(E)), 5'-adenylyl-beta,gamma-imidodiphosphate (A(PNP))-bound, and ADP (A(DP))-bound forms of the catalytic A subunit of the energy producer A(1)A(O) ATP synthase from Pyrococcus horikoshii OT3 have been solved at 2.47 A and 2.4 A resolutions. The structures provide novel features of nucleotide binding and depict the residues involved in the catalysis of the A subunit. In the A(E) form, the phosphate analog SO(4)(2-) binds, via a water molecule, to the phosphate binding loop (P-loop) residue Ser238, which is also involved in the phosphate binding of ADP and 5'-adenylyl-beta,gamma-imidodiphosphate. Together with amino acids Gly234 and Phe236, the serine residue stabilizes the arched P-loop conformation of subunit A, as shown by the 2.4-A structure of the mutant protein S238A in which the P-loop flips into a relaxed state, comparable to the one in catalytic beta subunits of F(1)F(O) ATP synthases. Superposition of the existing P-loop structures of ATPases emphasizes the unique P-loop in subunit A, which is also discussed in the light of an evolutionary P-loop switch in related A(1)A(O) ATP synthases, F(1)F(O) ATP synthases, and vacuolar ATPases and implicates diverse catalytic mechanisms inside these biological motors.
School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore.