Platinum plasmonic nanostructure arrays for massively parallel single-molecule detection based on enhanced fluorescence measurements.

We fabricated platinum bowtie nanostructure arrays producing fluorescence enhancement and evaluated their performance using two-photon photoluminescence and single-molecule fluorescence measurements. A comprehensive selection of suitable materials was explored by electromagnetic simulation and Pt was chosen as the plasmonic material for visible light excitation near 500 nm, which is preferable for multicolor dye-labeling applications like DNA sequencing. The observation of bright photoluminescence (λ = 500-600 nm) from each Pt nanostructure, induced by irradiation at 800 nm with a femtosecond laser pulse, clearly indicates that a highly enhanced local field is created near the Pt nanostructure.

An interactive gene network for securin-separase, condensin, cohesin, Dis1/Mtc1 and histones constructed by mass transformation.

The small genome of fission yeast Schizosaccharomyces pombe contains 4824 predicted genes and gene disruption suggests that approximately 850 are essential for viability. To obtain information on interactions among genes required for chromosome segregation, an approach called Strategy B was taken using mass transformation of the 1015 temperature-sensitive (ts) mutants that were made by random mutagenesis and transformed by plasmids carrying the genes for securin, separase, condensin, cohesin, kinetochore microtubule-binding proteins Dis1/Mtc1 or histones. Mutant strains whose phenotypes were either suppressed or inhibited by plasmids were selected.

A brute force postgenome approach to identify temperature-sensitive mutations that negatively interact with separase and securin plasmids.

Background: The fission yeast Schizosaccharomyces pombe separase/Cut1 and securin/Cut2 are required for anaphase-specific activation of proteolysis that leads to proper sister chromatid separation. We intended to identify ts (temperature sensitive) strains whose growth was inhibited by multicopy plasmid pCUT1 or pCUT2 at the permissive temperature.

Results: After a one-by-one transformation of 1015 randomly isolated ts strains, 18 transformants that retarded in colony formation at the permissive or semipermissive temperature were isolated.