1.9.6.1 ? 1 * 17000 (NapB) + 1 * 90000 (NapA), the NapA holoenzyme associates with a di-heme c-type cytochrome redox partner (NapB). NapA and NapB proteins purify independently and not as a tight heterodimeric complex. Dissociation constants of 0.015 mM and 0.032 mM are determined for oxidized and reduced NapAB complexes, respectively 674891 1.9.6.1 ? x * 16000 + x * 90000, SDS-PAGE 684990 1.9.6.1 ? x * 90000 + x * 16000, two-subunit complex, NapA is an 90000 Da catalytic subunit which binds a bis-molybdenum guanosine dinucleoside cofactor and a [4Fe4S] cluster. NapB is an 16000 Da electron-transfer subunit, which in other bacteria binds two c-type haems 654561 1.9.6.1 dimer 1 * 93000 + 1 * 16000, SDS-PAGE 697696 1.9.6.1 heterodimer - -, 741958 1.9.6.1 heterodimer 1 * 17000 + 1 * 87000, SDS-PAGE -, 698544 1.9.6.1 heterodimer 1 * 90000 (NapA) + 1 * 16000 (NapB), Nap activity is lost rapidly during the separation of NapA from NapB by anion exchange chromatography, SDS-PAGE 697968 1.9.6.1 heterodimer 1 * 93309 + 1 * 18924, calculated from sequence -, 698544 1.9.6.1 additional information PELDOR analysis of recombinant MTSL-labelled MalE-NapASP fusion mutant S4C/S24C alone or in complex with NapD, comparison of bound, NMR-derived NapASP helix from PDB ID 2PQ4 versus free generated helix, positions of the spin labels in the two conformations of the signal peptide, overview 742486 1.9.6.1 additional information the catalytic subunit of Nap is usually encoded in a nap operon together with accessory proteins involved in its maturation (chaperones) and redox proteins that transfer reducing equivalents from the physiological electron donor (quinone pool) to the active site of the enzyme, nap enzyme domain structure analysis, overview -, 742319