β-Barrel outer membrane proteins (OMPs) are found in the outer membranes of Gram-negative bacteria and are essential for nutrient import, signaling, and adhesion. A 200-kilodalton five-component complex called the β-barrel assembly machinery (BAM) complex has been implicated in the biogenesis of OMPs. We report the structure of the BAM complex from Escherichia coli, revealing that binding of Ba...

Structure-prediction and hydrophobic-cluster analysis of several starch hydrolases and related enzymes indicated the organization of eleven domain types. Most enzymes possess a catalytic (beta/alpha)8-barrel and a smaller C-terminal domain as seen in crystal structures of alpha-amylase and cyclodextrin glucanotransferase. Some also have a starch-granule-binding domain. Enzymes breaking or formi...

The FhuA protein in the outer membrane of Escherichia coli actively transports ferrichrome and the antibiotics albomycin and rifamycin CGP 4832 and serves as a receptor for the phages T1, T5, and phi80 and for colicin M and microcin J25. The crystal structure reveals a beta-barrel with a globular domain, the cork, which closes the channel formed by the barrel. Genetic deletion of the cork resul...

barrel vaults are attractive space structures that cover large area without intermediate supports. in this paper, the charged search system (css) optimization algorithm is employed for optimal design of barrel vaults. this method utilizes the governing laws of coulomb and gauss from electrostatics and the newtonian law of mechanics. the results demonstrate the efficiency of the discrete css alg...

The mitochondrial outer membrane contains proteinaceous machineries for the translocation of precursor proteins. The sorting and assembly machinery (SAM) is required for the insertion of β-barrel proteins into the outer membrane. Sam50 is the channel-forming core subunit of the SAM complex and belongs to the BamA/Sam50/Toc75 family of proteins that have been conserved from Gram-negative bacteri...

beta-Barrel proteins constitute a distinct class of mitochondrial outer membrane proteins. For import into mitochondria, their precursor forms engage the TOM complex. They are then relayed to the TOB complex, which mediates their insertion into the outer membrane. We studied the structure-function relationships of the core component of the TOB complex, Tob55. Tob55 precursors with deletions in ...

The (βα)8-barrel is a versatile single-domain protein fold that is adopted by a large number of enzymes. The (βα)8-barrel fold has been used as a model to elucidate the structural basis of protein thermostability and in studies to interconvert catalytic activities or substrate specificities by rational design or directed evolution. Recently, the (βα)4-half-barrel was identified as a possible st...