23VK

Crystal structure of full-length of APS kinase from Entamoeba histolytica

Summary for 23VK

• Entry DOI: 10.2210/pdb23vk/pdb
• Descriptor: adenylyl-sulfate kinase, SULFATE ION (3 entities in total)
• Functional Keywords: transferase, kinase, sulfate activation
• Biological source: Entamoeba histolytica
• Total number of polymer chains: 4
• Total formula weight: 222835.69

Authors

Hatanaka, R.,Yuasa, H.,Inoguchi, A.,Matsui, H.,Osumi, Y.,Mi-ichi, F.,Kishikawa, J.,Shiba, T. (deposition date: 2026-02-20, release date: 2026-06-03, Last modification date: 2026-06-10)

Primary citation

Hatanaka, R.,Ohsumi, Y.,Matsui, H.,Inoguchi, A.,Yuasa, H.,Mi-Ichi, F.,Kishikawa, J.I.,Shiba, T.
Structural insights into interdomain interactions in Entamoeba histolytica APS kinase.
J Struct Biol X, 13:100147-100147, 2026

PubMed Abstract: The biosynthetic pathway of 3'-phosphoadenosine-5'-phosphosulfate (PAPS) is a universal and essential metabolic process in many organisms, providing the activated sulfate donor required for the synthesis of diverse sulfated metabolites. However, this pathway has undergone substantial evolutionary diversification among species. In , PAPS biosynthesis occurs within the mitosomes, mitochondrion-related organelles (MROs), representing a distinctive example of lineage-specific evolutionary adaptation. PAPS synthesis proceeds through a conserved two-step process, which is sequentially catalyzed by ATP sulfurylase (AS) and adenosine 5'-phosphosulfate (APS) kinase (APSK). In this study, we focused on APSK (APSK). APSK contains an additional AS-like domain (SLD), although its functional role remains unclear. Here, we determined the crystal structure of full-length APSK at 2.60 Å resolution and the structure of the truncated APSK lacking APS kinase domain (KD) (APSK) at 2.10 Å resolution. Structural analyses revealed that the SLD engages in dynamic contacts with the KD. Furthermore, deletion of the domain and mutational analyses indicated that the SLD significantly influences the catalytic activity of the KD. Based on these findings, we propose a new regulatory mechanism in which transient interdomain interactions modulate APS kinase activity, representing an unique evolutionary adaptation of .

PubMed: 42212241
DOI: 10.1016/j.yjsbx.2026.100147

Experimental method

X-RAY DIFFRACTION (2.595 Å)