Organometallic bioconjugate

Noor F, Kinscherf R, Bonaterra GA, Walczak S, W51H S, Metzler-Nolte N (2009) Enhanced cellular uptake and cytotoxicity studies of organometallic bioconjugates of the NLS peptide in Hep G2 cells. Chembiochem 10 493-502... 

Keywords Bioorganometallic chemistry Medicinal organometallic chemistry Metal carbonyls Metallocenes N-heterocyclic carbenes Peptides Peptide Bioconjugates Peptide synthesis Solid phase synthesis Tris(pyrazolyl)borate ligands... 

In the following sections, luminescent organometallic rhenium(I) and iridium(III) polypyridine complexes relying on the labelling or binding strategies mentioned above will be described. We focus on the molecular structures, spectroscopic and photophysical properties of the complexes, and the emissive behaviour and potential applications of the labelled bioconjugates. 

Covalent attachment has also been exploited for protein incorporation of non-native redox active cofactors. A photosensitive rhodium complex has been covalently attached to a cysteine near the heme of cytochrome c (67). The heme of these cytochrome c bioconjugates was photoreducible, which makes it possible for these artificial proteins to be potentially useful in electronic devices. The covalent anchoring, via a disulfide bond, of a redox active ferrocene cofactor has been demonstrated in the protein azurin (68). Not only did conjugation to the protein provide the cofactor with increased water stability and solubility, but it also provided, by means of mutagenesis, a means of tuning the reduction potential of the cofactor. The protein-aided transition of organometallic species into aqueous solution via increased solubility, stability and tuning are important benefits to the construction of artificial metalloproteins. 

Zubieta and coworkers have recently taken advantage of the fluorescent and luminescent properties of organometallic complexes of rhenium (and technetium) comprising certain aromatic ligand systems (Fig. 2.2.6). The nonradioactive Re(CO)3 bioconjugates with a formyl peptide receptor-targeting peptide (flVlLF), enabeled visualization... 

Figure 1.11 Structures of organometallic Au(l)-peptide bioconjugates. Prepared by Metzler-Nolte and coworkers [63].

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