Modulation of the Redox Potential and Electron/Proton Transfer Mechanisms in the Outer Membrane Cytochrome OmcF From .

The monoheme outer membrane cytochrome F (OmcF) from plays an important role in Fe(III) reduction and electric current production. The electrochemical characterization of this cytochrome has shown that its redox potential is modulated by the solution pH (redox-Bohr effect) endowing the protein with the necessary properties to couple electron and proton transfer in the physiological range. The analysis of the OmcF structures in the reduced and oxidized states showed that with the exception of the side chain of histidine 47 (His), all other residues with protonatable side chains are distant from the heme iron and, therefore, are unlikely to affect the redox potential of the protein.

Structural analysis of free and liganded forms of the Fab fragment of a high-affinity anti-cocaine antibody, h2E2.

A high-affinity anti-cocaine monoclonal antibody, designated h2E2, is entering phase 1 clinical trials for cocaine abuse therapy. To gain insight into the molecular details of its structure that are important for binding cocaine and cocaine metabolites, the Fab fragment was generated and crystallized with and without ligand. Structures of the unliganded Fab and the Fab fragment bound to benzoylecgonine were determined, and were compared with each other and with other crystallized anti-cocaine antibodies.

Structural and Functional Relevance of the Conserved Residue V13 in the Triheme Cytochrome PpcA from Geobacter sulfurreducens.

The triheme cytochrome PpcA from Geobacter sulfurreducens is highly abundant under several growth conditions and is important for extracellular electron transfer. PpcA plays a central role in transferring electrons resulting from the cytoplasmic oxidation of carbon compounds to the cell exterior. This cytochrome is designed to couple electron and proton transfer at physiological pH, a process achieved via the selection of dominant microstates during the redox cycle of the protein, which are ultimately regulated by a well-established order of oxidation of the heme groups.

The structure of PccH from Geobacter sulfurreducens - a novel low reduction potential monoheme cytochrome essential for accepting electrons from an electrode.

The structure of cytochrome c (GSU3274) designated as PccH from Geobacter sulfurreducens was determined at a resolution of 2.0 Å. PccH is a small (15 kDa) cytochrome containing one c-type heme, found to be essential for the growth of G.

Analysis of periplasmic sensor domains from Anaeromyxobacter dehalogenans 2CP-C: structure of one sensor domain from a histidine kinase and another from a chemotaxis protein.

Anaeromyxobacter dehalogenans is a δ-proteobacterium found in diverse soils and sediments. It is of interest in bioremediation efforts due to its dechlorination and metal-reducing capabilities. To gain an understanding on A.

Mitigation of X-ray damage in macromolecular crystallography by submicrometre line focusing.

Reported here are measurements of the penetration depth and spatial distribution of photoelectron (PE) damage excited by 18.6 keV X-ray photons in a lysozyme crystal with a vertical submicrometre line-focus beam of 0.7 µm full-width half-maximum (FWHM).

Structure of the catalytic domain of glucuronoyl esterase Cip2 from Hypocrea jecorina.

The structure of the catalytic domain of glucuronoyl esterase Cip2 from the fungus H. jecorina was determined at a resolution of 1.9 Å.

Structural insights into the modulation of the redox properties of two Geobacter sulfurreducens homologous triheme cytochromes.

The redox properties of a periplasmic triheme cytochrome, PpcB from Geobacter sulfurreducens, were studied by NMR and visible spectroscopy. The structure of PpcB was determined by X-ray diffraction. PpcB is homologous to PpcA (77% sequence identity), which mediates cytoplasmic electron transfer to extracellular acceptors and is crucial in the bioenergetic metabolism of Geobacter spp.

The Structural Biology Center 19ID undulator beamline: facility specifications and protein crystallographic results.

The 19ID undulator beamline of the Structure Biology Center has been designed and built to take full advantage of the high flux, brilliance and quality of X-ray beams delivered by the Advanced Photon Source. The beamline optics are capable of delivering monochromatic X-rays with photon energies from 3.5 to 20 keV (3.

Structure of a novel c7-type three-heme cytochrome domain from a multidomain cytochrome c polymer.

The structure of a novel c(7)-type cytochrome domain that has two bishistidine coordinated hemes and one heme with histidine, methionine coordination (where the sixth ligand is a methionine residue) was determined at 1.7 A resolution. This domain is a representative of domains that form three polymers encoded by the Geobacter sulfurreducens genome.

Family of cytochrome c7-type proteins from Geobacter sulfurreducens: structure of one cytochrome c7 at 1.45 A resolution.

The structure of a cytochrome c(7) (PpcA) from Geobacter sulfurreducens was determined by X-ray diffraction at 1.45 A resolution; the R factor is 18.2%.

Crystal structure of murine sCEACAM1a[1,4]: a coronavirus receptor in the CEA family.

CEACAM1 is a member of the carcinoembryonic antigen (CEA) family. Isoforms of murine CEACAM1 serve as receptors for mouse hepatitis virus (MHV), a murine coronavirus. Here we report the crystal structure of soluble murine sCEACAM1a[1,4], which is composed of two Ig-like domains and has MHV neutralizing activity.