"Identification and characterization of MtoA: a decaheme c-type cytochrome of the neutrophilic Fe(II)-oxidizing bacterium Sideroxydans lithotrophicus ES-1" (2012). The Gram-negative bacterium Sideroxydans lithotrophicus ES-1 (ES-1) grows on FeCO 3 or FeS at oxic–anoxic interfaces at circumneutral pH, and the ES-1-mediated Fe(II) oxidation occurs extracellularly. However, the molecular mechanism...

[Chemical reaction: See text] Conjugated, shape-persistent macrocycles based on [3 + 3] Schiff-base condensation are of interest for supramolecular materials. In an effort to develop new discotic liquid crystals based on these compounds, a series of macrocycles with peripheral alkoxy groups of varying length have been prepared. The synthesis and mechanism of formation have been probed by isolat...

A nitrate-dependent Fe(II)-oxidizing bacterium was isolated and used to evaluate whether Fe(II) chemical form or oxidation rate had an effect on the mineralogy of biogenic Fe(III) (hydr)oxides resulting from nitrate-dependent Fe(II) oxidation. The isolate (designated FW33AN) had 99% 16S rRNA sequence similarity to Klebsiella oxytoca. FW33AN produced Fe(III) (hydr)oxides by oxidation of soluble ...

Recent studies of bacterial Fe(II) oxidation at circumneutral pH by a newly-isolated lithotrophic β-Proteobacterium (strain TW2) are reviewed in relation to a conceptual model that accounts for the influence of biogenic Fe(III)-binding ligands on patterns of Fe(II) oxidation and Fe(III) oxide deposition in opposing gradients of Fe(II) and O2. The conceptual model envisions complexation of Fe(II...

Macrocycles play an increasing role in drug discovery, but their synthesis is often demanding. Computational tools that suggest macrocyclization based on a known binding mode and that estimate the binding affinity of these macrocycles could have a substantial impact on the medicinal chemistry design process. For both tasks, we established a workflow with high practical value. For five diverse p...

Interpretation of the Fe II(UV)/Mg II emission ratios from quasars has a major cosmological motivation. Both Fe and Mg are produced by short-lived massive stars. In addition, Fe is produced by accreting white dwarf supernovae somewhat after star formation begins. Therefore, we expect that the Fe/Mg ratio will gradually decrease with redshift. We have used data from the Sloan Digital Sky Survey ...

Azobenzene macrocycles were designed for switchable π-stacking interaction. After efficient preparation and characterization of azobenzene macrocycles containing electron rich as well as electron poor elements a dimeric analogue was synthesized, which formed reversibly 3D-networks. Gel formation was observed with aromatic solvents representing the first example of this type based on switchable ...

Soluble organic nanorods were prepared from phenylacetylene macrocycles using the topochemical polymerization of butadiyne moieties placed both inside and outside the macrocycles' skeletons. Macrocycles containing amide groups were self-assembled in a columnar fashion through the formation of an organogel in ethyl acetate. Upon irradiation with UV light, the Raman signals associated with butadi...

Abst ra : The structure and complexation properties of macrocycles containing atoms from the second row of the periodic table (e.g., sulfur and phosphorus) have received less attention than the corresponding properties of macrocycles containing only first row atoms (e.g., oxygen and nitrogen). We describe results in two areas: macrocyclic thioethers for chelation of late transition metal ions, ...

The Gram-negative bacterium Sideroxydans lithotrophicus ES-1 (ES-1) grows on FeCO(3) or FeS at oxic-anoxic interfaces at circumneutral pH, and the ES-1-mediated Fe(II) oxidation occurs extracellularly. However, the molecular mechanisms underlying ES-1's ability to oxidize Fe(II) remain unknown. Survey of the ES-1 genome for candidate genes for microbial extracellular Fe(II) oxidation revealed t...