Bongrae Cho

Identification of a structural motif of 23S rRNA interacting with 5S rRNA.

To identify RNA motifs interacting with 5S rRNA, a systematic evolution of ligands by exponential enrichment experiment was applied. Some of the resulting RNA aptamers contained a consensus sequence similar to the sequence in the loop region of helix 89 of 23S rRNA. We show that the synthetic helix 89 RNA motif indeed interacted with 5S rRNA and that the region around loop B of 5S rRNA was involved in this interaction. These results suggest the presence of a novel RNA–RNA interaction between 23S rRNA and 5S rRNA which may play an important role in the ribosome function.

Differential promoter usage of infA in response to cold shock in Escherichia coli.

Initiation factor 1 (IF1) is an essential protein in Escherichia coli involved in the initiation step of protein synthesis. The protein level of IF1 increases when E. coli cells are subjected to cold shock, however, it remains unclear as to how this increase occurs. The infA gene encoding IF1 contains two promoters, the distal P1 and the proximal P2 promoter. In this study, we found that infA mRNA was greatly increased, and that this increase resulted from transcriptional activation of P1, not P2, during cold shock although stability of transcripts from both promoters concomitantly increased.

Extermination of influenza virus H1N1 by a new visible-light-induced photocatalyst under fluorescent light

A new visible-light-induced photocatalyst based on several transition metals (iron, magnesium and manganese)-loaded TiO2 was evaluated for its anti-viral activity with influenza virus H1N1. Under a fluorescent lamp of 1000 lx, λ > 410 nm, the virus was eradicated to more than 99% within 30 min. Since this photocatalyst can be used for coating plastics, wall papers and walls, it would be desirable to use this photocatalyst to reduce viral transmission via droplets and aerosols as well as surface contact for disinfection.