3QIA

Crystal structure of P-loop G237A mutant of subunit A of the A1AO ATP synthase

Summary for 3QIA

• Entry DOI: 10.2210/pdb3qia/pdb
• Related: 1VDZ 3I4L 3I72 3I73 3IKJ 3M4Y 3MFY
• Descriptor: V-type ATP synthase alpha chain, (4S)-2-METHYL-2,4-PENTANEDIOL, ACETIC ACID, ... (5 entities in total)
• Functional Keywords: hydrolase, atp binding
• Biological source: Pyrococcus horikoshii; More
• Total number of polymer chains: 1
• Total formula weight: 66704.89

Authors

Ragunathan, P.,Manimekalai, M.S.S.,Jeyakanthan, J.,Gruber, G. (deposition date: 2011-01-26, release date: 2011-10-05, Last modification date: 2023-11-01)

Primary citation

Priya, R.,Kumar, A.,Manimekalai, M.S.,Gruber, G.
Conserved glycine residues in the P-loop of ATP synthases form a doorframe for nucleotide entrance.
J.Mol.Biol., 413:657-666, 2011

PubMed Abstract: The phosphate binding loop (GXXXXGKT(S)) is conserved in several mononucleotide-binding proteins with similar three-dimensional structures. Although variations in other amino acids have been noted, the first glycine and glycine-lysine residues are highly conserved in all enzymes, whose role is yet to be understood. Alanine substitutions for critically positioned glycines-G234, G237, and G239-were generated for the catalytic A-subunit of A-ATP synthase from Pyrococcus horikoshii OT3, and their crystal structures were determined. They showed altered conformation for the phosphate binding loop, with G234A and G237A becoming flat and with G239A taking an intermediate conformation, resulting in the active-site region being closed to nucleotide entry. Furthermore, the essential amino acids S238 and K240, which normally interact with the nucleotide, become inaccessible. These mutant structures demonstrate the role of the strictly conserved glycine residues in guarding the active-site region for nucleotide entrance in archaea-type ATP synthases.

PubMed: 21925186
DOI: 10.1016/j.jmb.2011.08.045

Experimental method

X-RAY DIFFRACTION (2.6 Å)