Bioinorganic motifs: towards functional classification of metalloproteins.
The habitat of bioinorganic motifs (BIMs) is at the interface of biological inorganic chemistry and bioinformatics. BIM is defined as a common structural feature shared by functionally related, but not necessarily homologous, proteins, and consisting of the metal atom(s) and first coordination shell ligands. BIMs appear to be suitable for classification of metal centres at any level, from groups of unrelated proteins with similar function to different functional states of the same protein, and for description of possible evolutionary relationships of metalloproteins. However, they have not attracted wide attention from the bioinformatics community. Although their presence is appreciated, they are difficult to predict-therefore the current 'high-throughput' initiatives are likely to miss or ignore them altogether. The protein sequence databases do not distinguish between proteins containing different prosthetic groups (unless they have different sequences) or between apo- and holoprotein. On the other hand, the protein structure databases include data on 'hetero compounds' of various origin but these data are often inconsistent. A number of specialized databases dealing with BIMs and attempts to classify them are reviewed. SUPPLEMENTARY INFORMATION: The additional bibliography and list of Internet resources on bioinorganic chemistry are available at http://www.ebi.ac.uk/ approximately kirill/biometal/ (+info)
Effect of pressure on electron transfer reactions in inorganic and bioinorganic chemistry.
Kinetic and thermodynamic studies involving the application of different high-pressure techniques, are very useful in gaining mechanistic information on the basis of volume changes that occur during inorganic and bioinorganic electron transfer reactions. The most fundamental type of electron transfer reaction concerns self-exchange reactions, for which the overall reaction volume is zero, and activation volumes can be measured and discussed. In the case of non-symmetrical electron transfer reactions, intra- and intermolecular processes can be studied and volume profiles can be constructed. Precursor complex formation can in some cases be recognized kinetically in such systems. Typical values of activation and reaction volumes are reviewed for various reversible and irreversible electron transfer reactions. Mechanistic conclusions reached on the basis of these parameters are presented. Volume profiles for electron transfer reactions enable a simplistic presentation of the reaction mechanism on the basis of intrinsic and solvational volume changes along the reaction coordinate. (+info)
Electron-nuclear double resonance spectroscopy (and electron spin-echo envelope modulation spectroscopy) in bioinorganic chemistry.
This perspective discusses the ways that advanced paramagnetic resonance techniques, namely electron-nuclear double resonance (ENDOR) and electron spin-echo envelope modulation (ESEEM) spectroscopies, can help us understand how metal ions function in biological systems. (+info)
Bioinorganic chemistry in the postgenomic era.
Genome sequencing has revolutionized all fields of life sciences. Bioinorganic chemistry is certainly not immune to this influence, which is presenting unprecedented challenges. A new goal for bioinorganic chemistry is the investigation of the linkages between inorganic elements and genomic information. This requires new advancements andor the development of new expertise in fields such as bioinformatics and genetics but also provides a driving force to push forward the exploitation of traditional analytical techniques and spectroscopic tools. The "case study" of metal homeostasis in cells is discussed to provide a flavor of the current evolution of the field. (+info)
The bioinorganic chemistry of iron in oxygenases and supramolecular assemblies.
The bioinorganic chemistry of iron is central to life processes. Organisms must recruit iron from their environment, control iron storage and trafficking within cells, assemble the complex, iron-containing redox cofactors of metalloproteins, and manage a myriad of biochemical transformations by those enzymes. The coordination chemistry and the variable oxidation states of iron provide the essential mechanistic machinery of this metabolism. Our current understanding of several aspects of the chemistry of iron in biology are discussed with an emphasis on the oxygen activation and transfer reactions mediated by heme and nonheme iron proteins and the interactions of amphiphilic iron siderophores with lipid membranes. (+info)
Biological inorganic chemistry at the beginning of the 21st century.
Advances in bioinorganic chemistry since the 1970s have been driven by three factors: rapid determination of high-resolution structures of proteins and other biomolecules, utilization of powerful spectroscopic tools for studies of both structures and dynamics, and the widespread use of macromolecular engineering to create new biologically relevant structures. Today, very large molecules can be manipulated at will, with the result that certain proteins and nucleic acids themselves have become versatile model systems for elucidating biological function. (+info)
Sub-micrometer anatomical models of the sarcolemma of cardiac myocytes based on confocal imaging.
We describe an approach to develop anatomical models of cardiac cells. The approach is based on confocal imaging of living ventricular myocytes with submicrometer resolution, digital image processing of three-dimensional stacks with high data volume, and generation of dense triangular surface meshes representing the sarcolemma including the transverse tubular system. The image processing includes methods for deconvolution, filtering and segmentation. We introduce and visualize models of the sarcolemma of whole ventricular myocytes and single transversal tubules. These models can be applied for computational studies of cell and sub-cellular physical behavior and physiology, in particular cell signaling. Furthermore, the approach is applicable for studying effects of cardiac development, aging and diseases, which are associated with changes of cell anatomy and protein distributions. (+info)
Current applications and future potential for bioinorganic chemistry in the development of anticancer drugs.