Laboratory for Material Science in Life

http://www.sci.osaka-cu.ac.jp/chem/seitai/index_e.html

Current Research and Principal Research Interests
Selected Publications

1. Current Research and Principal Research Interests
Living organisms are rich sources of bioactive and functional compounds. We focus on isolationand structure elucidation of compounds with significant bioactivities and novel functions.
Furthermore, we provide a sufficient amount of such compounds by chemical synthesis tounderstand their modes of action. Clarifying the molecular mechanism of their functions isessential for research on structure-activity relationships, molecular recognition, interaction withreceptors. We are working at establishing strategies and methods with which to synthesize
biologically active compounds.
1.1 Studies on isolation and structure elucidation of biologically active compounds fromprotozoan ciliates, especially on the conjugation of the mating cells and on the predator-prayinteraction.
Studies on the conjugation of Blepharisma japonicum.

Structural elucidation of sugar part of blepharmone (gamone 1), a mating inducing
glycoprotein of mating Type I of Blepharisma japonicum.

Elucidation of a receptor for blepharismone (gamone 2), a second mating inducing substance.

Studies on the defense toxins of ciliates. We showed that the pigments stentorin andblepharismin from ciliates Stentor coeruleus and Blepharisma japonicum respectively function
as the defense toxin against predatory ciliates.

We determined the structure of the defense toxin climacostol and its congeners isolated fromciliate Climacostomum virens. The structure was confirmed by the total synthesis.

We also determined the structure of defense toxin spirostomin isolated from ciliate
Spirostomum teres.

1.2 Synthetic studies on biologically active compounds.
Total synthesis of climacostol and its congeners.
Total synthesis of stentorin.
Synthesis of a photoaffinity and fluorescence labelled probes for search of a receptor of
blepharismone (gamone 2).
Synthetic studies on the sugar part of blepharmone (gamone 1).
Synthetic studies on blepharismin.
Synthetic studies on spirostomin.

2. Selected Publications
1. "Developmentally and environmentally regulated gene expression of gamone 1, the trigger
molecule for sexual reprodiction in the ciliate Blepharisma japonicum", M. Sugiura, S.
Kawahara, H. Iio, T. Harumoto, J. Cell Sci., 118, 2735-2741 (2005).
2. "Semi-synthesis and biological evaluation of analogues of UK-2A, a novel antifungal
antibiotic from Streptomyces sp. 517-02", Y. Usuki, K. Mitomo, N. Adachi, X. Ping, K.-I. Fujita,
O. Sakanawa. K. Iinuma, H. Iio , M. Taniguchi, Bioorg. Med. Chem. Lett., 15, 2011-2014(2005).

3. "Climacostol, a defense toxin of Climacostomum virens (protozoa, ciliata), and its congeners",
M. E. Masaki, S. Hiro, Y. Usuki, T. Harumoto, M. N. Terazima, F. Buonanno, A. Miyake, andH. Iio, Tetrahedron, 60(33), 7041-7048 (2004): "Chemical defense by means of extrusive
cortical granules in the heterotrich ciliate Climacostomum virens", Miyake, A.; Buonanno, F.;
Saltalamacchia, P.; Masaki, M. E.; Iio, H. Eur. J. Protistol., 39, 25-36 (2003).
4. "Inhibition of mitochondrial respiration by climacostol", Muto, Y.; Tanabe, Y.; Kawai, K.; Iio,H., Jpn. J. Protozool.,36(1), 25-26 (2003).
5. "UK-2A, B, C and D, novel antifungal antibiotics from Streptomyces sp 517-02 VI (2).
Structure-activity relationships of UK-2A", Usuki Y, Goto K, Kiso T, Tani K, Ping X, Fujita
K.-I, Iio, H., Taniguchi M., J Antibiot., 55(6), 607-610 (2002).
6. "DNA cleavage by blepharismin and climacostol", Terazima, M. N.; Iio, H.; Harumoto, H.
Jpn. J. Protozool., 34(1), 60 (2001).
7. "2-Ethoxycarbonyl-2-fluoroaziridines: Methylene-bridged (Cα to N) α-Fluoro-α-amino Acids
Analogues", Usuki, Y.; Fukuda, Y.; Iio, H., ITE Letters on Batteries, New Technologies &Medicine, 2(2), C29-C32 (2001).
8. "Fluorinated Benzyloxy-methoxy Allylsilane: Preparation and itsFluoride-induced
Nucleophilic Reactivity", Usuki, Y.; Kobayashi, O.; Ohmura, Y.; Iio, H., ITE Letters onBatteries, New Technologies & Medicine, 2(3), C12-C14 (2001).
9. "Defence function of pigment granules in Stentor coeruleus", Miyake A.; Harumoto T.; Iio
H., Eur. J. Protistol., 37, 77-88 (2001).
10. "Asymmetric synthesis of isohaliclorensin, a key intermediate of bisquinolinylpyrrole
alkaloid halitulin", Usuki, Y.; Hirakawa, H.; Goto, K.; Iio H., Tetrahedron: Asymmetry, 12,3293-3296 (2001).