Abstract: The present invention relates to a composition for suppressing neuraminidase activity comprising a geranylated flavonoid derived from Paulownia tomentosa as an active ingredient. The Paulownia tomentosa extract and the geranylated flavonoid isolated therefrom exhibit an effect in significantly suppressing neuraminidase, which is an enzyme that plays an important role in the occurrence of pathogenic viral and bacterial infections and of the inflammation that accompanies such infection, and thus the Paulownia tomentosa extract or the geranylated flavonoid isolated therefrom can advantageously be used as an active ingredient in a composition for inhibiting neuraminidase activity.

Abstract: The present invention relates to a composition for suppressing neuraminidase activity comprising a geranylated flavonoid derived from Paulownia tomentosa as an active ingredient. The Paulownia tomentosa extract and the geranylated flavonoid isolated therefrom exhibit an effect in significantly suppressing neuraminidase, which is an enzyme that plays an important role in the occurrence of pathogenic viral and bacterial infections and of the inflammation that accompanies such infection, and thus the Paulownia tomentosa extract or the geranylated flavonoid isolated therefrom can advantageously be used as an active ingredient in a composition for inhibiting neuraminidase activity.

Abstract: There are disclosed a crystal of complex of RRF with a detergent, its crystallization method and a method for identifying an inhibitor for RRF by using the three-dimensional structure of RRF analyzed from the crystal. In the present invention, a crystal of RRF complexed with a detergent is obtained in the presence of the detergent, and the three-dimensional structure of RRF is analyzed from the crystal. There are identified an active site forming hydrophobic cleft and binding site of RRF to A-site of ribosome in the three-dimensional structure of RRF. The three-dimensional structure of RRF, specifically, the active site and binding site can allow an inhibitor for RRF to be designed and identified efficiently. RRF is essential for viability in prokaryotes, but is not essential in eukaryotes. From this fact, the inhibitor for RRF can be used as an antibiotic.

Abstract: A crystal of E. coli RRF complexed with a detergent is disclosed as well as the three-dimensional structure of the complex as analyzed by X-ray diffraction. The crystallization method and a method for identifying an inhibitor of RRF based on the identified three-dimensional structure is also disclosed. The RRF crystal was obtained in the presence of a detergent, and the three-dimensional structure of RRF was analyzed from this crystal. The active site forming a hydrophobic cleft and the binding site of RRF to the A-site of the ribosome was identified in the three-dimensional structure of RRF. The three-dimensional structure of RRF, and particularly, the active site and binding site can aid in the identification or modeling of an inhibitor for RRF. Because RRF is essential for viability in prokaryotes, but is not essential in eukaryotes the inhibitor can be used as an antibiotic.