Previously, the 126-kDa Bordetella pertussis CyaA pore-forming/hemolysin (CyaA-Hly) domain was shown to retain its hemolytic activity causing lysis of susceptible erythrocytes. Here, we have succeeded in producing, at large quantity and high purity, the His-tagged CyaA-Hly domain over-expressed in Escherichia coli as a soluble hemolytically-active form. Quantitative assays of hemolysis against ...

The structure of glutamate receptor-channel (GluR) subunits has recently been shown to differ from that of other ligand-gated channels and to contain a voltage-gated channel-like pore-forming motif. The view that the structure of GluR complexes is similar to the pentameric structure of other ligand-gated channels was questioned here. Studies of the response properties of the GluR1 subunit of th...

In this paper, we proposed 10 Gb/s transmission using 4-channel polymer waveguides on the optical electronic printed circuit board. It was simulated by the ray tracing method for tolerance study of optical interconnection and fabrication. In order for easy fabrication and high position accuracy, the polymer waveguides were forming silver coated 45° reflective mirrors by dicing method and e-beam...

The one-dimensional, cylindrical nature of single-walled carbon nanotubes SWCNTs suggests that the ideal gating geometry for nanotube field-effect transistors FETs is a surround gate SG . Using vertical SWCNTs templated in porous anodic alumina, SGs are formed using top-down processes for the dielectric/metal depositions and definition of the channel length. Surround gates allow aggressive scal...

Ion channel functional diversity can be achieved at the structural level by means of three main mechanisms: (1) transcriptional regulation and processing of mRNA, (2) heteromerization of different pore-forming channel subunits and (3) incorporation of regulatory subunits to the functional channel complex. In this review article we will focus on one of these mechanisms, alternative pre-mRNA spli...

Combined with high-resolution atomic-level crystal structures of channel forming peptides, theory has become a powerful tool for illuminating factors influencing permeation. Here, advantages and limitations of the more familiar continuum and molecular modeling techniques are briefly outlined. These methods are applied to issues of permeation in two different channel families: gramicidin and K(+...

Transmembrane transport is an essential component of the cell life. Many genes encoding known or putative transport proteins are found in bacterial genomes. In most cases their substrate specificity is not experimentally determined and only approximately predicted by comparative genomic analysis. Even less is known about the 3D structure of transporters. Nevertheless, the published experimental...

Plasmids of the H incompatibility complex confer protection against all known channel-forming colicins (PacB character) and resistance to potassium tellurite (Te(r)) to Escherichia coli strains. A DNA clone (2.2 kbp) from plasmid Mip233 (IncHI3) expressing PacB-Te(r) phenotypes was studied. DNA sequence analysis revealed a high degree of homology with the enzyme O-acetylserine sulfhydrylase. Si...

The photodissociation dynamics of small I-(H2O)n(n=2-5) clusters excited to their charge-transfer-to-solvent (CTTS) states have been studied using photofragment coincidence imaging. Upon excitation to the CTTS state, two photodissociation channels were observed. The major channel (approximately 90%) is a two-body process forming neutral I+(H2O)n photofragments, and the minor channel is a three-...

Communication of mitochondria with the rest of the cell requires beta-barrel proteins of the outer membrane. All beta-barrel proteins are synthesized as precursors in the cytosol and imported into mitochondria by the general translocase TOM and the sorting machinery SAM. The SAM complex contains two proteins essential for cell viability, the channel-forming Sam50 and Sam35. We have identified t...