Biomedical subjects

Masayuki Wakabayashi

Publications and source records attributed to Masayuki Wakabayashi.

3 recordsLinked to original sources

PubMed2006

Biomolecular sensor based on fluorescence-labeled aptamer.

Fluorescent DNA probes for L-argininamide were developed by a combination of DNA aptamers and fluorophore-quencher pairs. These molecules were synthesized by a combination of pre- and post-synthetic modification methods. The fluorescence-labeled aptamer could detect L-argininamide specifically. The binding affinities were defined by the binding affinity of the original aptamer to indicate that the end labeling of the aptamer did not influence the affinities.

Aptamers, Nucleotide↗

PubMed2004

A homolog of Escherichia coli RecA in mitochondria of the cellular slime mold Dictyostelium discoideum.

The cellular slime mold Dictyostelium discoideum expresses a gene encoding a 452-amino-acid polypeptide that is 47% identical to Escherichia coli RecA. A recA-deficient E. coli, JE6651, was transformed by pYSN1, which was designed to express the truncated form of the D. discoideum gene, and used in suppression assays. The viability of the transformant, JE6651(pYSN1), increased following UV irradiation or mitomycin C treatment. Phage lambda (red(-) gam(-)), which required RecA activity for DNA packaging, formed plaques on a lawn of JE6651(pYSN1). These results indicate that the gene product has a DNA recombination activity. Fluorescence of D. discoideum protein fused with GFP was detected in mitochondria. The gene disruption mutant was hypersensitive to UV-light (254nm), mitomycin C and H(2)O(2), indicating that D. discoideum recA is important for survival following exposure to DNA damaging agents.

Amino Acid Sequence↗

PubMed2004

Detection of biomolecule by aptamer beacon.

Labeled oligodeoxyribonucleotide bearing fluorescent dyes at both ends and aptamer sequence for adenosine 5'-monophosphate (AMP) was synthesized. Fluorescence spectra of labeled aptamer were not so much different between with and without AMP. This result suggests the binding of AMP didn't cause the global structural change to the aptamer. Therefore, we used short complementary DNA (SCD) as an assistant DNA, which is an unmodified 11mer and have a complementary sequence of 5'-region of the labeled aptamer. In the presence of SCD, the fluorescence intensities decrease with increasing the concentration of AMP compared with a change in absence of SCD.

Adenosine Monophosphate↗