An artificial CO-releasing metalloprotein built by histidine-selective metallation.

We report the design and synthesis of an aquacarbonyl Ru(II) dication cis-[Ru(CO)2(H2O)4](2+) reagent for histidine (His)-selective metallation of interleukin (IL)-8 at site 33. The artificial, non-toxic interleukin (IL)-8-Ru(II)(CO)2 metalloprotein retained IL-8-dependent neutrophil chemotactic activity and was shown to spontaneously release CO in live cells.We thank the European Commission (Marie Curie CIG to G.J.L.B., Marie Curie IEF to O.B.), FCT Portugal (FCT Investigator to G.J.L.B.) and the EPSRC for generous funding.This is the final published version. It first appeared at http://pubs.rsc.org/en/Content/ArticleLanding/2015/CC/c4cc10204e#!divAbstract