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5. Influence of the liquid carbazole concentration on charge trapping in C60 sensitized photorefractive polymers.

Author

Ribierre, J. C., Aoyama, T., Kobayashi, T., Sassa, T., Muto, T., and Wada, T.

Subjects
CARBAZOLE, PHOTOPOLYMERS, OPTICAL properties of polymers, POLYMER testing, ION traps, TRAPPED-particle instabilities, SPECTROSCOPIC imaging
Abstract

We study by two-beam coupling experiments the photorefractive properties of a poly(Nvinylcarbazole) (PVK) matrix plasticized with different concentrations of 9-(2-ethylhexyl)carbazole (EHCz), so-called liquid carbazole, and doped with the photosensitizer C60 and the electro-optic push-pull chromophore 4-piperidinobenzylidene malonitrile. The steady state and dynamic photorefractive performances of these materials are optimized by tuning the concentration ratio between PVK and EHCz. In parallel, the trap density values are determined by a spectroscopic method based on the strong absorption of the C60- anion in the near infrared region and are compared with those obtained from the photorefractive measurements. The results obtained from both techniques are in good agreement and show the important role played by the liquid carbazole in the charge trapping processes and the photorefractive properties of C60 sensitized photorefractive polymers. [ABSTRACT FROM AUTHOR]

Published
2007
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7. Influence of the liquid carbazole concentration on charge trapping in [C.sub.60] sensitized photorefractive polymers

Author

Ribierre, J.C., Aoyama, T., Kobayashi, T., Sassa, T., Muto, T., and Wada, T.

Subjects
Photorefractive materials -- Analysis, Carbon compounds -- Electric properties, Physics
Abstract

The photorefractive properties of [C.sub.60] sensitized guest-host polymers plasticized with various concentrations of liquid carbazole are examined. Findings reveal the important role played by the liquid carbazole in the charge trapping processes.

Published
2007

10. Expression of Bax and Bcl-2 protein in the gerbil hippocampus following transient forebrain ischemia and its modification by phencyclidine

Author

Akira Hara, Hideki Mori, Masayuki Niwa, Tomohiko Iwai, Toshihiko Uematsu, and Sassa T

Subjects
Male, medicine.medical_specialty, Time Factors, Ischemia, Phencyclidine, Hippocampus, Apoptosis, Biology, Gerbil, Forebrain ischemia, Prosencephalon, Proto-Oncogene Proteins, Internal medicine, medicine, Animals, bcl-2-Associated X Protein, Neurons, General Medicine, medicine.disease, Immunohistochemistry, Endocrinology, Proto-Oncogene Proteins c-bcl-2, nervous system, Neurology, Ischemic Attack, Transient, NMDA receptor, Neurology (clinical), Gerbillinae, BAX Protein, Neuroscience, medicine.drug
Abstract

To determine the effect of phencyclidine (a noncompetitive NMDA receptor antagonist) on expression of Bax and Bcl-2 (apoptosis-regulating proteins) in gerbil hippocampus after transient forebrain ischemia, brain sections were immunohistochemically evaluated 48, 72, 96 h and 7 days following ischemia. In ischemic control animals, the expression of Bax in CA1 neurons was increased with time and peaked at 72 h, then disappeared at 96 h. In the phencyclidine (5 mg kg-1, intraperitoneally)-treated animals, the intensity of Bax expression at 72 h was weaker than that of ischemic control animals. Furthermore, at 96 h, Bax expression was still observed in CA1 neurons. No expression of Bcl-2 in the CA1 neurons was detected in either control or phencyclidine-treated animals. From these results, it is possible that NMDA receptor antagonists exert their preventive effect against delayed neuronal death through inhibition of Bax protein expression, although the precise relationship between the function of Bax protein and delayed neuronal death is still unclear.

Published
1997

11. General Lectures-(II)

Author

Toriie, S., Nakajima, M., Kohli, Y., Takebayashi, M., Misaki, F., Kobayashi, A., Hashimoto, Y., Mitsuyoshi, Y., Ida, K., Kawai, K., Fujita, R., Kumura, F., Takahashi, M., Ohsawa, H., Hasegawa, Y., Kidokoro, T., Jojima, Y., Miyoshi, H., Okumura, Y., Yokouchi, A., Asano, H., Uehara, A., Oka, S., Saito, H., Yaginuma, M., Yamamoto, T., Asano, A., Nakamura, M., Okada, Y., Tomioka, T., Tamesue, N., Ikeda, S., Kunisaki, T., Emura, T., Yasumoto, M., Someya, N., Goto, A., Morokuma, K., Sakamoto, H., Kasaki, Y., Imamura, K., Amano, I., Iwanaga, K., Okugawa, N., Ninomiya, K., Yoshida, S., Okabe, N., Shimogawa, Y., Nakajima M., Ida, K., Akasaka, Y., Shimamoto, K., Misaki, F., Toriie, S., Tada, M., Sugawara, K., Chikayasu, I., Takeda, H., Kawai, K., Shibue, T., Yamaguchi, A., Osame, T., Shimada, K., Hori, M., Irisa, T., Miura, Y., Hanamure, B., Chuman, Y., Sato, H., Kizu, M., Kasugai, T., Kuno, N., Aoki, I., Nitta, Y., Machii, A., Murakami, Y., Aiso, Y., Kitahara, N., Yoshizawa, Y., Hishinuma, Y., Nao, Y., Ishiyama, K., Watanabe, M., Kimura, T., Hara, T., Sakaue, S., Shinoda, T., Ito, R., Hayashi, K., Sugie, H., Sekizawa, H., Nakamura, S., Kondo, J., Tanaka, E., Taniguchi, T., Kanayama, M., Koizumi, S., Watabiki, S., Ikeda, S., Tamura, K., Okada, Y., Arai, T., Saito, T., Tojo, S., Furuya, M., Hanaue, H., Ogoshi, K., Murohisa, B., Uchimura, M., Ishigaki, J., Waki, S., Nakafuji, H., Iida, F., Aratake, K., Nakano, T., Ono, N., Hara, I., Sassa, T., Takahashi, T., Inoue, J., Maruyama, Y., Mori, Y., Kawamura, T., Imai, F., Yorita, S., Saegusa, M., Ishihara, F., Asukata, I., Matsuda, M., Wakabayashi, K., Mitani, S., Sugahara, K., Ishikawa, K., Nakayoshi, A., Nakamoto, M., Kono, A., Oda, T., Sato, Y., Takahashi, T., Nagao, F., Nagano, M., Furusawa, T., Nakama, T., Itoh, H., Nishimura, M., Tsutsumi, K., Saito, H., Yoshida, K., Ito, H., Yoshimura, M., Yoshioka, K., Shimizu, T., Kuroda, C., Uchida, H., Ishida, O., Inoue, T., Hasegawa, S., Mitsusada, K., Kajiyama, Y., Matsuzawa, Y., Yokota, K., Hayashida, Y., Ikegudhi, S., Shida, S., Tsurumi, K., Ito, K., Kamiya, K., Takada, H., Ueno, S., Onda, M., Kojima, G., Shoji, E., Miyaji, M., Goto, K., Nitta, Y., Yazaki, Y., Ito, M., Kozuka, M., Tanabe, A., Murate, H., Takeuchi, T., Koshikawa, M., Kato, N., Maeda, K., Hayashi, K., Tsuru, T., Ooyama, I., Kukimoto, H., Nakashima, Y., Katsuki, T., Ueda, N., Kanno, T., Noda, A., Toda, Y., Hayakawa, T., Nakajima, S., Morishita, R., Furukawa, K., Ikeda, F., Fujii, M., Yamamoto, T., Wakisaka, G., Matasumoto, Y., Ono, H., Hirose, S., Kobayashi, K., Sawabu, N., Takeuchi, J., Kajikawa, K., Takada, A., Hirai, Y., Ohki, I., Sato, K., Tasaka, S., Sato, A., Aono, G., Kidokoro, T., Takezoe, K., Jojima, Y., Ohara, T., Soma, S., Ukawa, S., Yamaguchi, S., Shirahama, T., Sugiyama, K., Koyama, H., Haga, M., Arikawa, H., Toyokawa, H., Sato, R., Ueno, Y., Karasawa, Y., Onuma, H., Suzuki, H., Murakami, T., Yasui, A., Ichinose, Y., Hirase, Y., Okazaki, T., Takai, T., Watanabe, K., Kato, M., Yamada, M., Tsuji, T., Kunito, Y., Kobayashi, S., Udo, K., Iriyama, K., Sugiura, Y., Takahashi, Y., Kawamura, O., Ando, S., Hayashi, K., Tsuji, K., Yukawa, Y., Saito, N., Miyazawa, M., Imai, K., Tabayashi, T., Ito, H., Umehara, S., Watanabe, Y., Murai, S., Nukaga, A., Ishimatsu, N., Sotoyama, S., Abe, M., Hirai, K., Yoshida, K., Aoki, T., Nagao, F., Aoki, Y., Taniguchi, K., Wada, N., Tabuse, K., Yanagi, I., Tsuhada, K., Katsumi, M., Nakamura, K., Takemoto, K., Yamaura, Y., Karibe, N., Yamada, G., Ichikawa, H., Ogiwara, M., Matsushita, M., Kobayashi, I., Kusano, M., Yasuna, O., Hayashi, S., Yoshizumi, M., Kojima, Y., Matsubayashi, K., Yamamoto, T., Nishimura, R., Koga, M., Tachibana, M., Kurata, M., Suto, H., Ichinose, I., Ishizuka, K., Shimoda, M., Onai, M., Akiyama, T., Sekiguchi, T., Kobayashi, S., Matsuyoshi, M., Yonezawa, N., Kasamatsu, M., Yokota, Y., Toyoda, T., Uchimoto, I., Kanamoto, M., Fukai, Y., Sugawara, K., Katoh, M., Takebayashi, M., Mitsuyoshi, Y., Shimamoto, K., Nakamura, I., Tamura, M., Nishio, M., Mukaide, Y., Kuzumoto, Y., Ota, K., Yoshida, T., Sakamoto, A., Akiyama, T., Kaneko, S., Yanagida, M., Kishimoto, S., Miyaji, K., Shiraki, Y., Inoue, K., Tamada, T., Usui, T., Ohtsuka, K., Yamada, S., Fujishima, S., Tamiya, A., Saji, K., Ueda, A., Shiraki, Y., Inoue, K., Tamada, T., Usui, T., Ohtsuka, K., Yamada, S., Fujishima, S., Tamiya, A., Saji, K., Ueda, A., Yasutake, K., Irie, K., Ijiri, Y., Sato, H., Nishijima, H., Ogino, K., Okuno, T., Date, H., Yao, T., Koga, Y., Tomioka, T., Fuyuno, S., Okabe, H., Mitsui, H., Tamechika, Y., Masuda, N., Fujiwara, T., Sakimura, M., Okada, Y., Takamura, Y., Kono, T., Kurihara, M., Sumida, M., Izumi, T., Haraikawa, M., Hayakawa, H., Shirakabe, H., Yasui, A., Ushio, K., Okamoto, M., Noguchi, M., Kinoshita, A., Yamada, T., Ichikawa, H., Shimotori, K., Kudo, T., Mukaida, I., Ishikawa, H., Sato, K., Shirane, T., Kano, A., Suzuki, T., Tanaka, M., Iwanaga, T., Taniguchi, H., Inawashiro, M., Endo, N., Kawamura, T., Suzuki, Sh., Suzuki, H., Maki, T., Hayakawa, K., Ikezawa, H., Jao, C. C., Yamada, K., Nakamura, M., Tanaka, M., Maruyama, M., Nagasako, K., Oi, I., Kozu, T., Yamashita, K., Yokoyama, I., Endo, M., Takemoto, T., Nakayama, K., Hayakawa, R., Ishiguro, M., Nakano, H., Nakazawa, S., Tsuboi, Y., Yamase, H., Yamashita, T., Fujita, T., Ishikawa, Y., Ito, N., Mitsuno, T., Kanazawa, K., Yamashiro, M., Kubo, T., Iizuka, H., Watanabe, T., Sanada, M., Satoh, H., Shimada, H., Kusama, S., Ishikawa, K., Ikeda, K., Naramoto, J., Koga, M., Okazaki, Y., Nakamura, K., Kawamura, S., Fujimoto, S., Urayama, S., Matsuura, H., Sekitani, T., Sasayama, T., Nakagawa, K., Toyama, K., Nakagawa, S., Takada, T., Kusaka, K., Takaba, S., Satomura, A., Suzuki, T., Kawakami, Y., Watanabe, Y., Suzuki, H., Koike, T., Joh, S., Hara, T., Tamura, K., Kobayagawa, K., Hashimoto, T., Uemura, F., Fukui, O., Takahashi, M., Takasato, Y., Shirakawa, K., Hisamatsu, M., Saito, T., Ashizawa, S., Sakurane, Y., Miyamura, K., Sasaki, H., Katsumi, M., Ura, S., Emoto, M., Tatsumi, Y., Totsuka, Y., Chiba, N., Ozeki, M., Nakazawa, M., Takamura, S., Iida, F., Sawano, Y., Sugita, T., Funabiki, T., Watanabe, S., Moriya, T., Tomita, N., Nishida, K., Todo, A., Miyake, T., Suzaki, Y., Yamamoto, Y., Ariyoshi, J., Hajiro, K., Oishi, M., Yanagihara, K., Nakamura, A., Kuramata, H., Soeda, S., Kondo, N., Akashi, M., Hemmi, T., Kadono, H., Ito, T., Tsuchiya, R., Ikeda, Y., Futatsuki, K., Nomoto, S., Kino, I., Arai, M., Shimazu, H., Kobori, O., Ishikawa, K., Hiroshima, Y., Matsusaka, Y., Katase, K., Sakuma, Y., Murata, N., Komura, K., Ando, H., Ohara, K., Hayashi, A., Suzuki, M., Watanuki, T., Asano, T., Koide, N., Shiobara, M., Matsuo, N., Imai, K., Segawa, K., Nakazawa, S., Okabe, N., Kawai, K., Matsumoto, K., Shimada, H., Machida, K., Koizumi, Y., Hoshi, Y., Oi, M., Watanuki, T., Seki, H., Matsumura, M., Kimura, M., Yoshimura, M., Ishikawa, I., Kishi, S., Kondo, Y., Uchida, Y., Harada, H., Mandai, M., Kikuchi, T., Mishima, K., Yamagata, Y., Suyama, T., Kawagoe, K., Inagawa, T., Kishimoto, S., Sugiya, T., Kai, T., Miyoshi, A., Fukumoto, S., Watanabe, K., Kojo, H., Turuhara, I., Miyoshi, Y., Okamoto, K., Inata, H., Okamoto, H., Sakurai, S., Sugiyama, M., Sasaki, H., Miura, K., Kurihara, T., Sakumoto, K., Okita, E., Tanaka, H., Ishihara, K., Okawa, M., Okumura, Y., Watanabe, Y., Nishizaki, N., Murakami, T., Saito, K., Aoyagi, K., Hamaguchi, E., Kitamura, T., Matsuo, Y., Seki, A., Mori, H., Ishikawa, T., Nakajima, T., Shimomura, T., Sengoku, K., Aoyagi, K., Hamaguchi, E., Uchiya, Y., Yabana, T., Konta, M., Kamijo, K., Yachi, A., Okuse, S., Ohara, H., Sato, K., Wada, T., Kurata, M., Furuta, K., Nishii, M., Yamawaki, T., Nishii, K., Umeda, K., Yoshida, H., Ito, H., Okabayashi, T., Kato, Y., Yatsuji, Y., Suzuki, Y., Nomura, K., Matsumoto, K., Kamisaka, K., Motoki, T., Kamii, K., Kameda, H., Imamura, H., Uchiya, T., Ishizawa, M., Nishizaki, H., Murakami, T., Orimo, H., Yoshida, A., Yoshida, A., Orimo, H., Fujita, T., Oda, T., Itoh, Z., Honda, R., Takeuchi, S., Fukushima, T., Suda, T., Shinonaga, M., Ishiguro, N., Fujisawa, S., Nishiyama, K., and Ohkubo, T.

Published
1973
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12. Chemical Defence and Toxins of Plants

Author

Yamane, H., Konno, K., Sabelis, M., Takabayashi, J., Sassa, T., Oikawa, H., Mander, L., Lui, H.W., and Population Biology (IBED, FNWI)

Subjects
Herbivore, Microbial pathogenesis, Chlorosis, Polyketide synthase, Botany, biology.protein, food and beverages, Wilting, Chemical defense, Biology
Abstract

Higher plants protect themselves by producing a variety of secondary metabolites and proteins that are involved in defense against herbivores as well as microbial pathogens. Concerning microbial pathogenesis in plants, in many cases, it is known that phytotoxins that are produced by plant pathogens play an important role in disease development causing chlorosis, necrosis, or wilting. This chapter mainly focuses on the chemical structures, distribution, and biosynthesis of defense-related natural products and phytotoxins.

Published
2010

13. Decreased prefrontal dopamine D1 receptors in schizophrenia revealed by PET

Author

Okubo, Y, Suhara, T, Suzuki, K, Kobayashi, K, Inoue, O, Terasaki, O, Someya, Y, Sassa, T, Sudo, Y, Matsushima, E, Iyo, M, Tateno, Y, and Toru, M

Abstract

Schizophrenia is believed to involve altered activation of dopamine receptors, and support for this hypothesis comes from the antipsychotic effect of antagonists of the dopamine D2 receptor (D2R). D2R is expressed most highly in the striatum, but most of the recent positron emission tomography (PET) studies have failed to show any change in D2R densities in the striatum of schizophrenics, raising the possibility that other receptors may also be involved. In particular, the dopamine D1 receptor (D1R), which is highly expressed in the prefrontal cortex, has been implicated in the control of working memory, and working memory dysfunction is a prominent feature of schizophrenia. We have therefore used PET to examine the distribution of D1R and D2R in brains of drug-naive or drug-free schizophrenic patients. Although no differences were observed in the striatum relative to control subjects, binding of radioligand to D1R was reduced in the prefrontal cortex of schizophrenics. This reduction was related to the severity of the negative symptoms (for instance, emotional withdrawal) and to poor performance in the Wisconsin Card Sorting Test. We propose that dysfunction of D1R signalling in the prefrontal cortex may contribute to the negative symptoms and cognitive deficits seen in schizophrenia.

Published
1997

18. UPDATABLE 3D HOLOGRAPHIC DISPLAY SYSTEM: S-INNOVATION PROJECT'S STRATEGY AND FUTURE PERSPECTIVES.

Author

Tsutsumi, N., Kinashi, K., Kawabe, Y., Tada, K., Fukuzawa, K., Sasaki, T., Naka, Y., Sassa, T., and Fujihara, T.

Subjects
HOLOGRAPHIC displays, FERROELECTRIC liquid crystals, TRIPHENYLAMINE, TECHNOLOGICAL innovations, DIFFRACTION gratings
Abstract

We present a strategy to achieve an updatable three-dimensional (3D) holographic display system currently developed by our S-innovation project. Photorefractive polymers are promising materials for an updatable 3D holographic display and imaging. Triphenylamine-based photorefractive (PR) polymer composites have a high potential for a holographic display device with the fast response time of 2.2 ms and the high diffraction efficiency of 59 % under an applied field of 60 V µm-1. A PR ferroelectric liquid crystal system gave a faster response time of 900 µs and an extremely large optical gain up to 1200 cm-1. In addition to these advanced PR composites, PR-like monolithic compound with no-bias field gave great potentials for a 3D holographic diffraction application. Further a molecular designing of PR composites promises an updatable full-color 3D holographic display system. [ABSTRACT FROM AUTHOR]

Published
2014

26. ORIGINS OF MODE COUPLING IN GRADED-INDEX PLASTIC OPTICAL FIBERS WITH MICROSCOPIC HETEROGENEOUS STRUCTURES.

Author

Inoue, A., Suga, M., Makino, K., Kondo, A., Sassa, T., and Koike, Y.

Subjects
MODE-coupling theory (Phase transformations), GRADED index fibers, PLASTIC optical fibers, STATISTICAL correlation, RANDOM variables
Abstract

Mode coupling due to the intrinsic heterogeneities in graded-index plasitc optical fiber (GI POF) core was studied. The coupled power equation was modified with consideration of the isotropic random heterogeneities and the dependence of the power coupling coefficient to the correlation characteristics of the microscopic heterogeneous structure was discussed. It suggested that the mode coupling between the guided modes is maximized for the specific correlation length of the heterogeneities. [ABSTRACT FROM AUTHOR]

Published
2011

42. RANDOM POWER TRANSITION IN MICROSCOPICALLY HETEROGENEOUS PLASTIC OPTICAL FIBERS.

Author

Inoue, A., Sassa, T., and Koike, Y.

Subjects
PLASTIC optical fibers, POLYMETHYLMETHACRYLATE, GRADED index fibers, OPTICAL interference, SPECKLE interference
Abstract

We investigated influence of the microscopic core heterogeneities on modal noise in poly(methyl methacrylate) (PMMA)-based graded-index plastic optical fibers (GI POFs). The speckle contrast of the output mode interference pattern was theoretically evaluated with consideration of random mode coupling due to the heterogeneities, using the developed coupled power equation. The results suggest that modal noise can be decreased in the PMMA-based GI POF through random power transition with little mode-dependent loss. [ABSTRACT FROM AUTHOR]

Published
2012

43. OPTICAL TRANSMISSION BANDWIDTH OF POLY(METHYL METHACRYLATE)-BASED GRADED-INDEX OPTICAL FIBERS WITH MICROSCOPIC HETEROGENEITIES.

Author

Suzuki, R., Inoue, A., Suga, M., Sassa, T., and Koike, Y.

Subjects
BANDWIDTHS, LIGHT transmission, PLASTIC optical fibers, POLYMETHYLMETHACRYLATE, FABRICATION (Manufacturing), SCATTERING (Physics)
Abstract

We experimentally evaluated the influence of microscopic heterogeneities on light transmission characteristics of poly(methyl methacrylate)-based graded-index plastic optical fiber (GI POF) fabricated by interfacial gel polymerization. The GI POF had few differential mode attenuation because the fabrication method results in no steep refractive index change of core-cladding boundary. On the other hand, the transmission bandwidth was significantly affected by mode coupling. These results suggest that the mode coupling in the GI POF can be predominantly induced by density-fluctuation-induced volume scattering. [ABSTRACT FROM AUTHOR]

Published
2012

44. FLUORINATION EFFECTS ON ATTENUATION SPECTRA OF POLYSTYRENE-BASED OPTICAL FIBER MATERIALS.

Author

Takahashi, A., Inoue, A., Sassa, T., and Koike, Y.

Subjects
FLUORINATION, ATTENUATION (Physics), PLASTIC optical fibers, ABSORPTION spectra, VIBRATIONAL spectra, POLYSTYRENE
Abstract

We investigated how partial fluorination of a phenyl group affects the CH stretching vibrational absorptions of polystyrene-based optical fiber materials. We confirmed that the fluorination can decrease not only number density of CH bonds but also the CH absorption per bond. Moreover, by quantitatively correlating the CH stretching vibration absorption spectra with anharmonic vibrational potential, we suggested that the decrease efficiency of attenuation depends on the substituted position in the benzene ring and the chemical structure itself. [ABSTRACT FROM AUTHOR]

Published
2012

46. Immunomodulatory Constituents from an Ascomycete, Eupenicillium crustaceum, and Revised Absolute Structure of Macrophorin D

Author

Fujimoto, H., Nakamura, E., Kim, Y.-P., Okuyama, E., Ishibashi, M., and Sassa, T.

Abstract

Fractionation guided by immunomodulatory activity of the EtOAc extract of the Ascomycete Eupenicillium crustaceum has afforded two new naturally occurring products, 4‘-oxomacrophorin D (1) and 4‘-oxomacrophorin A (2), as the immunosuppressive components of this fungus [1:  3-hydroxy-3-methylglutaryl (HMG) conjugate of 2]. The structures including the absolute configurations of 1 and 2 have been determined on the basis of chemical correlation of 1 with macrophorin D (3). The absolute configuration of the HMG moiety in 3 has been revised from 3R to 3S.

Published
2001

47. Simultaneous Determination of Average Direction of Molecular Orientation and Effective Second Order Nonlinear Optical Constant (|d<SUP> eff</SUP>|) by Phase Measurements of Second Harmonic Generation

Author

Kimura-Suda, H., Sassa, T., Wada, T., and Sasabe, H.

Abstract

We present a new analytical method of molecular orientation in films using a phase measurement of second harmonic generation (SHG) with a theoretical curve fitting. The new analytical method provides the average direction of molecules and the absolute value of the effective second-order nonlinear optical constant (|d eff|) simultaneously. In conventional methods, the average direction of molecules in a sample has been relatively determined with that in a standard sample having preknown molecular direction. The second harmonic (SH) interference fringe obtained between a reference having preknown molecular direction and the sample has been compared with that between the reference and the standard sample. In the new method, however, the average direction of molecules can be obtained without the standard sample. The value of |d eff| is calculated through the fitting process, the average direction of molecules is determined by the sign or the phase of d eff, which is introduced by a reference. Complete expression with physical meanings is given for the valley points and the contrast of SH interference fringe. There, effect of a lens to focus a fundamental wave to a sample is also taken into account. The new phase measurement of SHG with the curve fitting has been carried out with poled poly(methyl methacrylate) films doped with 2 wt % of p-nitroaniline (PNA/PMMA), which were used as a reference and also as a sample. The accuracy of the new method has been demonstrated in comparison of the value |d eff| of the sample with that determined by Maker fringe measurement. The determined average direction of molecules for the sample was confirmed by experimental geometry of the reference and the sample and also from the poling geometry for the sample. We have shown that the phase measurement of SHG and the curve fitting are useful tools to investigate the molecular orientation.

Published
2001

48. Functional analysis of the two interacting cyclase domains in ent-kaurene synthase from the fungus Phaeosphaeria sp. L487 and a comparison with cyclases from higher plants.

Author

Kawaide, H, Sassa, T, and Kamiya, Y

Abstract

We report here kinetic analysis and identification of the two cyclase domains in a bifunctional diterpene cyclase, Phaeosphaeria ent-kaurene synthase (FCPS/KS). Kinetics of a recombinant FCPS/KS protein indicated that the affinity for copalyl diphosphate is higher than that for geranylgeranyl diphosphate (GGDP). ent-Kaurene production from GGDP by FCPS/KS was enhanced by the addition of a plant ent-kaurene synthase (KS) but not by plant CDP synthase (CPS), suggesting that the rate of ent-kaurene production of FCPS/KS may be limited by the KS activity. Site-directed mutagenesis of aspartate-rich motifs in FCPS/KS indicated that the (318)DVDD motif near the N terminus and the (656)DEFFE motif near the C terminus may be part of the active site for the CPS and KS reactions, respectively. The other aspartate-rich (132)DDVLD motif near the N terminus is thought to be involved in both reactions. Functional analysis of the N- and C-terminal truncated mutants revealed that a N-terminal 59-kDa polypeptide catalyzed the CPS reaction and a C-terminal 66-kDa polypeptide showed KS activity. A 101-kDa polypeptide lacking the first 43 amino acids of the N terminus reduced KS activity severely without CPS activity. These results indicate that there are two separate interacting domains in the 106-kDa polypeptide of FCPS/KS.

Published
2000

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