The purple membrane is a two-dimensional crystalline lattice formed by bacteriorhodopsin and lipid molecules in the cytoplasmic membrane of Halobacterium salinarum. High-resolution structural studies, in conjunction with detailed knowledge of the lipid composition, make the purple membrane one of the best models for elucidating the forces that are responsible for the assembly and stability of i...

In 1988 the United Nations Children's Fund (UNICEF) established a research centre to support its advocacy for children worldwide and to identify and research current and future areas of UNICEF's work. The prime objectives of the Office of Research are to improve international understanding of issues relating to children's rights and to help facilitate full implementation of the Convention on th...

We identify a structural feature of transmembrane helical proteins that restricts their conformational space and suggests a new way of understanding the construction and stability of their native states. We show that five kinds of well-known specific favorable interhelical interactions (hydrogen bonds, aromatic interactions, salt bridges, and two interactions from packing motifs) precisely dete...

Many adaptive evolutionary systems display spatial and temporal features, such as long-range correlations, typically associated with the critical point of a phase transition in statistical physics. Empirical and theoretical studies suggest that operating near criticality enhances the functionality of biological networks, such as brain and gene networks, in terms for instance of information proc...

Small-molecule Tau aggregation inhibitors are under investigation as potential therapeutic agents against Alzheimer disease. Many such inhibitors have been identified in vitro, but their potency-driving features, and their molecular targets in the Tau aggregation pathway, have resisted identification. Previously we proposed ligand polarizability, a measure of electron delocalization, as a candi...

Perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) are thought to induce peroxisome proliferation and interfere with mitochondrial metabolic pathways. Direct measurements revealed that PFOA and the unsubstituted sulfonamide of perfluorooctane (FOSA) uncouple mitochondrial respiration by increasing proton conductance. The purpose of this investigation was to characterize structural de...

Site selectivity of protein N-linked glycosylation is dependent on many factors, including accessibility of the modification site, amino acids that make up the glycosylation consensus sequence and cellular localization of target proteins. Previous studies have shown that the bacterial oligosaccharyltransferase, PglB, of Campylobacter jejuni favors acceptor proteins with consensus sequences (D/E...

Neural connections of the mammalian cerebral cortex exhibit specific patterns ranging in scale from interconnections linking whole brain regions to intra-areal patterns of connections between cell populations or individual cortical neurons (Cajal, 1909; Brodmann, 1909; Zeki, 1993; Salin and Bullier, 1995; Swanson, 2003). Detailed anatomical and physiological studies have revealed many of the ba...

Transposases are important tools in genome engineering, and there is considerable interest in engineering more efficient ones. Here, we seek to understand the factors determining their activity using the Sleeping Beauty transposase. Recent work suggests that protein coevolutionary information can be used to classify groups of physically connected, coevolving residues into elements called "secto...

A method for determining the kinetic fate of structured disulfide species (i.e., whether they are preferentially oxidized or reshuffle back to an unstructured disulfide species) is introduced. The method relies on the sensitivity of unstructured disulfide species to low concentrations of reducing agents. Because a structured des species that preferentially reshuffles generally first rearranges ...