ProteoVision is a web server designed to explore protein structure and evolution through simultaneous visualization of multiple sequence alignments, topology diagrams and 3D structures. Starting with a multiple sequence alignment, ProteoVision computes conservation scores and a variety of physicochemical properties and simultaneously maps and visualizes alignments and other data on multiple levels of representation. The web server calculates and displays frequencies of amino acids.
View Article and Find Full Text PDFMitochondrial ribosomes (mitoribosomes) are essential components of all mitochondria that synthesize proteins encoded by the mitochondrial genome. Unlike other ribosomes, mitoribosomes are highly variable across species. The basis for this diversity is not known.
View Article and Find Full Text PDFThe Universal Gene Set of Life (UGSL) is common to genomes of all extant organisms. The UGSL is small, consisting of <100 genes, and is dominated by genes encoding the translation system. Here we extend the search for biological universality to three dimensions.
View Article and Find Full Text PDFWe present a molecular-level model for the origin and evolution of the translation system, using a 3D comparative method. In this model, the ribosome evolved by accretion, recursively adding expansion segments, iteratively growing, subsuming, and freezing the rRNA. Functions of expansion segments in the ancestral ribosome are assigned by correspondence with their functions in the extant ribosome.
View Article and Find Full Text PDFRiboVision is a visualization and analysis tool for the simultaneous display of multiple layers of diverse information on primary (1D), secondary (2D), and three-dimensional (3D) structures of ribosomes. The ribosome is a macromolecular complex containing ribosomal RNA and ribosomal proteins and is a key component of life responsible for the synthesis of proteins in all living organisms. RiboVision is intended for rapid retrieval, analysis, filtering, and display of a variety of ribosomal data.
View Article and Find Full Text PDFThe origins and evolution of the ribosome, 3-4 billion years ago, remain imprinted in the biochemistry of extant life and in the structure of the ribosome. Processes of ribosomal RNA (rRNA) expansion can be "observed" by comparing 3D rRNA structures of bacteria (small), yeast (medium), and metazoans (large). rRNA size correlates well with species complexity.
View Article and Find Full Text PDFAccurate secondary structures are important for understanding ribosomes, which are extremely large and highly complex. Using 3D structures of ribosomes as input, we have revised and corrected traditional secondary (2°) structures of rRNAs. We identify helices by specific geometric and molecular interaction criteria, not by co-variation.
View Article and Find Full Text PDFWe present a de novo re-determination of the secondary (2°) structure and domain architecture of the 23S and 5S rRNAs, using 3D structures, determined by X-ray diffraction, as input. In the traditional 2° structure, the center of the 23S rRNA is an extended single strand, which in 3D is seen to be compact and double helical. Accurately assigning nucleotides to helices compels a revision of the 23S rRNA 2° structure.
View Article and Find Full Text PDFSome of the magnesium ions in the ribosome are coordinated by multiple rRNA phosphate groups. These magnesium ions link distal sequences of rRNA, primarily by incorporating phosphate groups into the first coordination shell. Less frequently, magnesium interacts with ribosomal proteins.
View Article and Find Full Text PDFMg²⁺ shares a distinctive relationship with RNA, playing important and specific roles in the folding and function of essentially all large RNAs. Here we use theory and experiment to evaluate Fe²⁺ in the absence of free oxygen as a replacement for Mg²⁺ in RNA folding and catalysis. We describe both quantum mechanical calculations and experiments that suggest that the roles of Mg²⁺ in RNA folding and function can indeed be served by Fe²⁺.
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