Download MendeleyStructure of Nm23-H1 under oxidative conditions.
Kim, M.S., Jeong, J., Jeong, J., Shin, D.H., Lee, K.J.(2013) Acta Crystallogr D Biol Crystallogr 69: 669-680
- PubMed: 23519676
- DOI: https://doi.org/10.1107/S0907444913001194
- Primary Citation of Related Structures:
4ENO - PubMed Abstract:
Nm23-H1/NDPK-A, a tumour metastasis suppressor, is a multifunctional housekeeping enzyme with nucleoside diphosphate kinase activity. Hexameric Nm23-H1 is required for suppression of tumour metastasis and it is dissociated into dimers under oxidative conditions. Here, the crystal structure of oxidized Nm23-H1 is presented. It reveals the formation of an intramolecular disulfide bond between Cys4 and Cys145 that triggers a large conformational change that destabilizes the hexameric state. The dependence of the dissociation dynamics on the H2O2 concentration was determined using hydrogen/deuterium-exchange experiments. The quaternary conformational change provides a suitable environment for the oxidation of Cys109 to sulfonic acid, as demonstrated by peptide sequencing using nanoUPLC-ESI-q-TOF tandem MS. From these and other data, it is proposed that the molecular and cellular functions of Nm23-H1 are regulated by a series of oxidative modifications coupled to its oligomeric states and that the modified cysteines are resolvable by NADPH-dependent reduction systems. These findings broaden the understanding of the complicated enzyme-regulatory mechanisms that operate under oxidative conditions.
Organizational Affiliation:
The Center for Cell Signaling and Drug Discovery Research, College of Pharmacy, Division of Life and Pharmaceutical Sciences, Ewha Womans University, Seoul, Republic of Korea.
