Biochemical and structural insight into the chemical resistance and cofactor specificity of the formate dehydrogenase from Starkeya novella.

Formate dehydrogenases (Fdhs) mediate the oxidation of formate to carbon dioxide and concomitant reduction of nicotinamide adenine dinucleotide (NAD ). The low cost of the substrate formate and importance of the product NADH as a cellular source of reducing power make this reaction attractive for biotechnological applications. However, the majority of Fdhs are sensitive to inactivation by thiol-modifying reagents.

De novo rational design of a freestanding, supercharged polypeptide, proton-conducting membrane.

Proton translocation enables important processes in nature and man-made technologies. However, controlling proton conduction and fabrication of devices exploiting biomaterials remains a challenge. Even more difficult is the design of protein-based bulk materials without any functional starting scaffold for further optimization.

Ru-Based CO releasing molecules with azole ligands: interaction with proteins and the CO release mechanism disclosed by X-ray crystallography.

fac-[Ru(CO)Cl(N-Imidazole)] (RuIM), fac-[Ru(CO)Cl(N-methyl-imidazole)] (RuMIM) and fac-[Ru(CO)Cl(N-methyl-benzimidazole)] (RuMBI) are three ruthenium based CO releasing molecules (Ru-CORMs) that are cytotoxic towards ovarian and colon carcinoma cell lines. Detailed structural information on the adducts formed upon reaction of RuIM and RuMIM with hen egg white lysozyme and of the three Ru-CORMs with bovine pancreatic ribonuclease is provided here by X-ray crystallography. Comparative analysis of seven crystal structures of these adducts allows one to delineate some general trends in the reactivity of these Ru-CORMs with proteins.

X-ray Structure of the Carboplatin-Loaded Apo-Ferritin Nanocage.

The second-generation Pt anticancer agent carboplatin (CBDCA) was encapsulated within the apo horse spleen ferritin (AFt) nanocage, and the X-ray structure of the drug-loaded protein was refined at 1.49 Å resolution. Two Pt binding sites, different from the one observed in the cisplatin-encapsulated AFt, were identified in Ft subunits by inspection of anomalous electron density maps at two wavelengths and difference Fourier electron density maps, which provide the necessary sensitivity to discriminate between Pt from CBDCA and Cd ions that are present in the crystallization conditions.

A driving force for polypeptide and protein collapse.

Experimental measurements and computational results have shown that polypeptide chains, made up of 15-25 glycine residues, collapse to compact structures in water at room temperature. This contrasts with the classic idea that the burial of nonpolar side chains, i.e.

Gold-based drug encapsulation within a ferritin nanocage: X-ray structure and biological evaluation as a potential anticancer agent of the Auoxo3-loaded protein.

Auoxo3, a cytotoxic gold(iii) compound, was encapsulated within a ferritin nanocage. Inductively coupled plasma mass spectrometry, circular dichroism, UV-Vis absorption spectroscopy and X-ray crystallography confirm the potential-drug encapsulation. The structure shows that naked Au(i) ions bind to the side chains of Cys48, His49, His114, His114 and Cys126, Cys126, His132, His147.

Cisplatin encapsulation within a ferritin nanocage: a high-resolution crystallographic study.

Cisplatin (CDDP) can be encapsulated within the central cavity of reconstituted (apo)ferritin, (A)Ft, to form a drug-loaded protein of potential great interest for targeted cancer treatments. In this study, the interactions occurring between cisplatin and native horse spleen Ft in CDDP-encapsulated AFt are investigated by high-resolution X-ray crystallography. A protein bound Pt center is unambiguously identified in AFt subunits by comparative analysis of difference Fourier electron density maps and of anomalous dispersion data.