Structures of Fission Yeast Inositol Pyrophosphate Kinase Asp1 in Ligand-Free, Substrate-Bound, and Product-Bound States.

ABSTRACT: Expression of the fission yeast Schizosaccharomyces pombe phosphate regulon is sensitive to the intracellular level of the inositol pyrophosphate signaling molecule 1,5-IP₈. IP₈ dynamics are determined by Asp1, a bifunctional enzyme consisting of an N-terminal kinase domain and a C-terminal pyrophosphatase domain that catalyze IP₈ synthesis and catabolism, respectively. Here, we report structures of the Asp1 kinase domain, crystallized with two protomers in the asymmetric unit, one of which was complexed with ligands (ADPNP, ADP, or ATP; Mg²⁺ or Mn²⁺; IP₆, 5-IP₇, or 1,5-IP₈) and the other which was ligand-free. The ligand-free enzyme adopts an "open" conformation that allows ingress of substrates and eg

SUBMITTER: Benjamin B 

PROVIDER: S-EPMC9765450 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature