We show that for two well-characterized regulatory circuits in Escherichia coli, Tn10 tetracycline resistance and porin osmoregulation, the transcriptional outputs in individual cells are graded functions of the applied stimuli. These systems are therefore examples of naturally occurring regulatory circuits that exhibit continuous control of transcription. Surprisingly, however, we find that po...

In this study, the effect of solvents, HCl and aqua regia at room temperature, on the etching behavior of ITO film was investigated. A higher etching rate was obtained in aqua regia than in HCl. However, via XPS analysis, it was found that there was more surface residual byproduct in aqua regia etchant than in HCl. The surface concentration (ratio of chlorine to indium) was 7.2 and 0.38 in aqua...

Purpose: Epidermal growth factor receptor (EGFR) overexpression correlates with recurrence and with treatment resistance in head and neck squamous cell carcinoma (HNSCC). The aim of this study was to evaluate the relationship of EGFR gene copy number utilizing FISH and protein expression with automated quantitative analysis (AQUA) and to correlate those with patient outcome. Experimental Design...

One potential vaccine strategy in the fight against meningococcal disease involves the exploitation of outer-membrane components of Neisseria lactamica, a commensal bacterium closely related to the meningococcus, Neisseria meningitidis. Although N. lactamica shares many surface structures with the meningococcus, little is known about the antigenic diversity of this commensal bacterium or the an...

The algorithms for estimating snow extent for the Moderate Resolution Imaging Spectroradiometer (MODIS) optimally use the 1.6-μm channel which is unavailable for MODIS on Aqua due to detector damage. As a test bed to demonstrate that Aqua band 6 can be restored, we chose the area surrounding Yellowstone and Grand Teton national parks. In such rugged and difficult-to-access terrain, satellite im...

The outer membrane of mycobacteria presents an effective permeability barrier for many antibiotics. Transport pathways across this membrane are unknown for most drugs. Here, we examined which antibiotics utilize the porin pathway across the outer membrane of the model organism Mycobacterium smegmatis. Deletion of the porins MspA and MspC drastically increased the resistance of M. smegmatis ML10...

Mitochondrial porin forms channels in the outer mitochondrial membrane which allows the passage of molecules with diameters up to -20 A [l-6]. We have described the purification of this protein [7] from purified outer membranes by differential extraction with detergents and anionic exchange chromatography. The purified porin displayed an app. Mr of 31 000 as judged by polyacrylamide gel electro...

A protein with an apparent M(r) of 28,000 was isolated from outer membrane preparations of Aeromonas salmonicida A440. The protein was tested for the ability to form pores, using a planar lipid bilayer model membrane system. The protein appeared to be a monomer with a single-channel conductance in 1.0 M KCl of 1.96 nS and a cation/anion permeability ratio of 2.91 +/- 0.68. These data show that ...

Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2 An oligonucleotide that encodes the N-terminal portion of a 41 kDa porin of Serratia marcescens was used to probe S. marcescens UOC-51 genomic DNA. An 11 kb EcoRl fragment which hybridized with the oligonucleotide was subcloned into Escherichia coli, examined for expression, and sequenced. The product express...

Pseudomonas aeruginosa common surface antigens were compared in a permeability mutant (PCC118) and its parent (PAO503). The distribution of lipopolysaccharide and porin antigens in the mutant supports the conclusion that beta-lactam permeability was affected by lipopolysaccharide-side chain presentation rather than by a change in porin number.