Influence of the presence of the heme cofactor on the JK-loop structure in indoleamine 2,3-dioxygenase 1.
Mirgaux, M., Leherte, L., Wouters, J.(2020) Acta Crystallogr D Struct Biol 76: 1211-1221
- PubMed: 33263327 
- DOI: https://doi.org/10.1107/S2059798320013510
- Primary Citation of Related Structures:  
7A62 - PubMed Abstract: 
Indoleamine 2,3-dioxygenase 1 has sparked interest as an immunotherapeutic target in cancer research. Its structure includes a loop, named the JK-loop, that controls the orientation of the substrate or inhibitor within the active site. However, little has been reported about the crystal structure of this loop. In the present work, the conformation of the JK-loop is determined for the first time in the presence of the heme cofactor in the active site through X-ray diffraction experiments (2.44 Å resolution). Molecular-dynamics trajectories were also obtained to provide dynamic information about the loop according to the presence of cofactor. This new structural and dynamic information highlights the importance of the JK-loop in confining the labile heme cofactor to the active site.
Organizational Affiliation: 
Namur Institute of Structured Matter (NISM), Namur Research Institute for Life Science (NARILIS), Department of Chemistry, Laboratoire de Chimie Biologique Structurale (CBS), University of Namur (UNamur), 61 Rue de Bruxelles, 5000 Namur, Belgium.