Interaction of metal nanoparticles with recombinant arginine kinase from Trypanosoma brucei: Thermodynamic and spectrofluorimetric evaluation

Proposed structure of the binding sites for TbAK showing the interaction of silver/gold nanoparticles through Cys271, interfering with N1 of the arginine substrate. The interatomic distance between the thiolate atom of Cys271 and N1 of the arginine substrate is 3.3 Å. The interatomic distance between Trp104 and N1 is 22.2 Å while that distance between Trp104 and bound Ag/Au nanoparticles is 21.1 Å and 22.6 Å respectively. Nitrate not shown.368