Crystal structure of A-type ATP synthase catalytic nucleotide-binding subunit A from Pyrococcus horikoshii reveals a novel domain related in the

H+-transporting ATP synthase is a multi-subunit enzyme involved in the production of ATP, which is essential molecule for living organisms as a source of energy. Archaeal A-type ATPase (A-ATPase) is thought to act as a functional ATP synthase in Archaea and is thought to have chimeric properties of F-ATPase and V-ATPase. From the previous structural studies of F-ATPase, it is indicated that the major nucleotide-binding subunits α and β consist of three domains. The catalytic nucleotide-binding subunit A of V/A-ATPase contains an insertion of about 90 residues, which is absent from the F1-β subunit. Here we describe the first X-ray structure of the catalytic nucleotide-binding subunit A of the A1-ATPase determined at 2.55 Å resolution. A1-ATPase subunit A from Pyrococcus horikoshii consists of four domains. A novel domain, including a part of this insertion, corresponds to the “knob-like structure” observed in electron microscopy of A1-ATPase. Based on the structure, it is highly likely that this inserted domain is related to the peripheral stalk common to the A- and V-ATPases. The arrangement of this inserted domain suggests that this region plays an important role in A-ATPase as well as in V-ATPase

Cloning, expression, purification and preliminary crystallographic studies of the adenylate/uridylate-rich element-binding protein HuR complexed with its target RNA

An RNA-binding region of human HuR bound to an 11-base RNA fragment has been crystallized. The crystals diffracted to a resolution of 1.8 Å and belonged to space group P212121