Vaults are cytoplasmic ribonucleoprotein organelles that are highly conserved among diverse eukaryotic species. Their mass (12.9 MDa), diameter (26-35 nm) and shape (two halves, each with eightfold radial symmetry) have recently been determined and are similar to those ascribed to the central plug (or transporter) of the nuclear pore complex (NPC). The size and eightfold symmetry of the vault p...

We report the biochemical and biophysical characterization of outer membrane protein X (OmpX), an eight-stranded transmembrane β-barrel from E. coli, and compare the barrel behavior with a mutant devoid of methionine residues. Transmembrane outer membrane proteins of bacterial origin are known to display high tolerance to sequence rearrangements and mutations. Our studies with the triple mutant...

The structure of phosphoribosyl anthranilate isomerase (TrpF) from the hyperthermophilic archaeon Pyrococcus furiosus (PfTrpF) has been determined at 1.75 Å resolution. The PfTrpF structure has a monomeric TIM-barrel fold which differs from the dimeric structures of two other known thermophilic TrpF proteins. A comparison of the PfTrpF structure with the two known bacterial thermophilic TrpF st...

• TNA assessment of masonry vaults by solving nonlinear constrained optimisations. A direct optimisation to find the minimum thickness, and GSF, vaults. Robustness vaulted structures through stability domain analyses. numerical approach for with geometry from point clouds. new SDV-based interactive algorithm select independent force densities. This paper presents a methodology assess using Thru...

During the past decade, the Protein Structure Initiative (PSI) centres have become major contributors of new families, superfamilies and folds to the Structural Classification of Proteins (SCOP) database. The PSI results have increased the diversity of protein structural space and accelerated our understanding of it. This review article surveys a selection of protein structures determined by th...

Chlamydia trachomatis is the most prevalent cause of bacterial sexually transmitted diseases and the leading cause of preventable blindness worldwide. Global control of Chlamydia will best be achieved with a vaccine, a primary target for which is the major outer membrane protein, MOMP, which comprises ~60% of the outer membrane protein mass of this bacterium. In the absence of experimental stru...

β-barrel membrane proteins (TMBs) perform a variety of functions in living organisms and these proteins contain β-strands as their membrane spanning segments. The membrane spanning segments of TMBs contain several charged and polar residues in contrast with a stretch of hydrophobic amino acid residues in transmembrane helical (TMH) proteins. Hence, most predictive schemes, which are successful ...

Despite efforts for over 25 years, de novo protein design has not succeeded in achieving the TIM-barrel fold. Here we describe the computational design of four-fold symmetrical (β/α)8 barrels guided by geometrical and chemical principles. Experimental characterization of 33 designs revealed the importance of side chain-backbone hydrogen bonds for defining the strand register between repeat unit...

β-barrel membrane proteins play an important role in controlling the exchange and transport of ions and organic molecules across bacterial and mitochondrial outer membranes. They are also major regulators of apoptosis and are important determinants of bacterial virulence. In contrast to β-helical membrane proteins, their evolutionary pattern of residue substitutions has not been quantified, and...

The developmental appearance of ameboid and ramified microglia in the rat brain has been examined by immunofluorescent localization of vaults, recently described ribonucleoprotein particles (Kedersha and Rome, 1986a). Vaults are distinct, multiarched structures of unknown function expressed by higher and lower eukaryotic species. Although vaults have been detected in all mammalian cells examine...