Conserved -Terminal Tail Is Responsible for Membrane Localization and Function of Hemerythrin.

Many bacteria have hemerythrin (Hr) proteins that bind O, including , in which microoxia-induced Hr (Mhr) provide fitness advantages under microoxic conditions. Mhr has a 23 amino-acid extension at its -terminus relative to a well-characterized Hr from , and similar extensions are also found in Hrs from other bacteria. The last 11 amino acids of this extended, -terminal tail are highly conserved in gammaproteobacteria and predicted to form a helix with positively charged and hydrophobic faces.

Applications of the Newly Developed Force-Field Parameters Uncover a Dynamic Nature of Ω-Loop C in the Lys-Ligated Alkaline Form of Cytochrome .

Lys-ligated cytochromes make up an emerging family of heme proteins. Density functional theory calculations on the amine/imidazole-ligated -type ferric heme were employed to develop force-field parameters for molecular dynamics (MD) simulations of structural and dynamic features of these proteins. The new force-field parameters were applied to the alkaline form of yeast -1 cytochrome to rationalize discrepancies resulting from distinct experimental conditions in prior structural studies and to provide insights into the mechanisms of the alkaline transition.

The structure of the diheme cytochrome c from Neisseria gonorrhoeae reveals multiple contributors to tuning reduction potentials.

Cytochrome c (c) is a diheme protein implicated as an electron donor to cbb oxidases in multiple pathogenic bacteria. Despite its prevalence, understanding of how specific structural features of c optimize its function is lacking. The human pathogen Neisseria gonorrhoeae (Ng) thrives in low oxygen environments owing to the activity of its cbb oxidase.

Influence of the Interdomain Interface on Structural and Redox Properties of Multiheme Proteins.

Multiheme proteins are important in energy conversion and biogeochemical cycles of nitrogen and sulfur. A diheme cytochrome () was used as a model to elucidate roles of the interdomain interface on properties of iron centers in its hemes A and B. Isolated monoheme domains -A and -B, together with the full-length diheme and its Met-to-His ligand variants, were characterized by a variety of spectroscopic and stability measurements.

Comparing Properties of Common Bioinorganic Ligands with Switchable Variants of Cytochrome .

Ligand substitution at the metal center is common in catalysis and signal transduction of metalloproteins. Understanding the effects of particular ligands, as well as the polypeptide surrounding, is critical for uncovering mechanisms of these biological processes and exploiting them in the design of bioinspired catalysts and molecular devices. A series of switchable K79G/M80X/F82C (X = Met, His, or Lys) variants of cytochrome (cyt) was employed to directly compare the stability of differently ligated proteins and activation barriers for Met, His, and Lys replacement at the ferric heme iron.